the annual report

Earth and Space Sciences
Annual Report 2014
Dear Reader,
In front of you is now again one of our department’s yearly reports. As chair of the department it
is sometimes meaningful — at least I like to think so — to reflect on what it is that characterizes
a department in general and of course our own department in particular? When reading about
the activities in the different research groups and the National Facility for Radio Astronomy
one realizes that there are indeed many common interests, but there are also many differences.
In a way the organization of our department seems a bit like a family structure. It provides a
framework, a platform, from which the different members, and constellations of members, may
operate. Another similarity is the probability for conflicts of interest. Therefore, just as in the
case of the family, there is a need for a limited amount of reasonable rules. These rules must be
followed and in return you receive support in terms of logistics. Some rules we may agree upon
internally and these are in general likely to be accepted. Other rules, that are given to us from
outside, such as laws, may in some cases be more difficult to accept. One such law is the Swedish
Public Procurement Act which for example specifies the procedures to use when we buy airplane
tickets or electronic components where a specific vendor is chosen as the only possible one for a
period of several years, regardless of if the price from others are lower. It causes frustration when
resources could be used much more efficiently. I think this an example of a difference between
the department and the family.
Gunnar Elgered,
Head of Department
Let us address another important issue. In a family we usually care about each other. A family
member is often willing to sacrifice quite a lot in order to help another family member through
difficult times. To what extent does that apply in our department? Well, I hope I will not have
to find out the answer to that question. In the mean time, in the yearly budget, we put aside a
small but significant amount of funds in order to be prepared for unforeseen difficulties. This is
however not of an amount that so far has caused any noticeable suffering.
On this page I usually also mention the promotions that have occurred during the last year. Today
I do that with mixed feelings. The reason is that Joachim (Jo) Urban who has been with us in the
department since 2004 was appointed as professor on the 1st of July. Just a few weeks later we
were reached by the sad news that he passed away while on vacation in Bordeaux, France.
In retrospect we are happy for the promotion and it was an accomplishment that Jo had strived
for. Please read more about Jo and his professional life on the next page.
Other announcements we are happy to make, without any mixed feelings, are:
• Cathy Horellou, was appointed Director of the master’s program Physics and Astronomy for a
three year period starting on the 1st of April;
• Lars Ulander, our former adjunct professor, was recruited as a full professor in Radar Remote
Sensing from the 1st of May;
• Kirsten Kraiberg Knudsen was appointed as associate professor in Radio Astronomy on the
1st of December.
Finally, reflecting about environmental issues please note that the cost for travel in the
department has not increased significantly over the last five years (see page 25). This is in spite
of that the department has grown and the extent of our international collaborations, indirectly
reflected by the amount of internationally coauthored papers listed towards the end of this report,
has increased during the same period. With this positive statement I like to sum up 2014 by saying
thank you to all my family — whoops, sorry, department members.
Production: Dept. of Earth &
Space Sciences, Chalmers
Printed by Chalmers
Reproservice, 2015. Copies:
750
2
In Memoriam
Earlier this year our dear colleague and friend Jo Urban passed away in Bordeaux, France.
As a leading expert in microwave and sub-mm atmospheric observations, he was very well known
and connected in the atmospheric chemistry and remote sensing community. Jo participated in
many international activities. He made important contributions to three SPARC (StratosphereTroposphere Processes and their Role in Climate) activities: Data Initiative (trace gas climatologies),
WAVAS II (water vapour assessment) and the SPARC/IO3C/IGACOO3/ NDACC (SI2N) “Activity
on Past changes in the Vertical Distribution of Ozone“. He collaborated in the still ongoing ESA
(European Space Agency) Climate Change Initiative (CCI) on ozone and was co-author of Chapter
2 “Global Ozone” of the current WMO/UNEP Scientific Assessment of Stratospheric Ozone
Depletion 2014.
Since 2004 he has worked at Chalmers where he was an essential part of the Odin team headed by
Prof. Donal Murtagh being responsible for microwave trace gas retrieval and science analysis using
data from SMR, which was successfully launched in 2001. He was also involved in the STEAM
concept, a follow-up on SMR, to be flown as part of the PREMIER limb sounder proposed to
the European Space Agency. After being an associate professor for several years, he just became
professor in July this year.
He was an outstanding scientist, leader in his field, well known and well liked. We have lost a good
friend and colleague.
“Our dead are never dead to us, until we have forgotten them.” George Elliot
Mark Weber, John P. Burrows, Harry Küllmann, and Donal Murtagh,
The Cover
In the world’s largest fusion experiment, the Joint European Torus
(JET), temperatures range from 100 million degrees in the core
to 1000 degrees near the wall – a distance of a mere meter. The
extreme conditions provide a challenge for physicists; theoretically,
experimentally, as well as numerically.
The strong gradients in temperature and density present in a
tokamak fusion plasma provide a source of free energy that couples
to the confining magnetic field and feeds instabilities over a wide
range of sizes and frequencies. The small scale instabilities in turn
drive turbulence, the presence and nature of which has important
repercussions for energy confinement. Turbulent motion act to
increase transport of fuel ions, heat and impurities across the magnetic
field lines, but can also act collectively to create large scale flows
that improve confinement. Understanding and predicting turbulent
transport requires the experimental effort to be supported by a
theoretical undertaking.
The cover shows micro-turbulent structures from a gyrokinetic
plasma simulation of the JET tokamak. Turbulence is more
pronounced on the outboard side of the tokamak, known as the bad
curvature region.
Contents
First Degree & Master’s Studies.........
......................... 4
Bachelor´s Thesis Reports................
............................. 5
Master’s Thesis Reports.......................
.......................... 5
Master´s Programmes.......................
.............................. 6
Doctoral Programme...........................
............................ 8
Doctoral Dissertations......................
.............................. 8
Licentiates.............................................
............................ 9
Advanced Receiver Development..
............................10
Global Environmental Measuremen
ts and
Modelling...............................................
..........................11
Optical Remote Sensing.......................
.......................12
Plasma Physics and Fusion Energy.
..........................13
Radar Remote Sensing......................
..........................14
Space Geodesy and Geodynamics
..........................15
Radio Astronomy and Astrophysic
s..........................16
Onsala Space Observatory...............
..........................18
Publications............................................
.........................21
Public Outreach/Press Clippings.....
.........................24
Facts and Figures..............................
............................25
Organisation............................................
........................26
Photo: EFDA/EUROfusion. Edit by Andreas Skyman, research group Plasma Physics and
Fusion Energy, Chalmers University of Technology.
3
First Degree
and Master’s Studies
Magnus Thomasson,
Vice Head of Department
and responsible for the
undergraduate teaching
Arto Heikkilä,
Director of the
Programme in
Electrical Engineering
The department is active at several levels of
teaching: we give courses for students at Chalmers’ Foundation Year, the three-year engineering
programme in Electrical Engineering and fiveyear master of engineering programmes in Electrical Engineering, Automation and Mechatronics
Engineering, and Engineering Physics. Most of
our courses are at the master’s level, and many of
them are also open for students at University of
Gothenburg.
In 2014, the department was responsible for more
than 20 courses at Chalmers, plus thesis projects
on bachelor’s and master’s level. Our teachers also
participated in courses given by other departments.
The subjects range from basic electrical engineering to courses closely related to our research in,
e.g., astrophysics, remote sensing, receiver development, and plasma physics. An important subject
is measurement techniques. We have our own
laboratory, which is used exclusively for teaching
and where students get hands-on experience with
measurement instruments. Also the instruments
at Onsala Space Observatory are used in several
courses. One example is the small radio telescope
SALSA, which astronomy students use to observe
atomic hydrogen gas in the Milky Way.
The department is involved in two master’s
programmes: Physics and Astronomy (together
with the Department of Fundamental Physics)
and Wireless, Photonics and Space Engineering
(together with the Department of Microtehnology
and Nanoscience).
One of the department’s teachers, Cathy Horellou, was appointed Director of the Master’s
Programme in Physics and Astronomy in 2014. She
has many years of experience from teaching and
supervising master’s students in astronomy. Since
2013 another of our teachers, Arto Heikkilä, is
Head of the Programme in Elecetrical Engineering.
Göta studentkår at the University of Gothenburg
awarded Alessandro Romeo with “Pedagogiska
priset” in 2014, in honor of his much appreciated
teaching ability. This year’s theme was “Commitment”, which we all can agree that Alessandro
possesses in abundance.
One new course was developed and given for the
first time in 2014: Stellar physics. The course complements the other astronomy courses in the in the
master’s programme Physics and Astronomy.
Chalmers courses given during 2014
Cathy Horellou,
Director of the
Master’s Programme
in Physics and
Astronomy
(NB: many of the master’s courses were also open to students at the University of Gothenburg)
A Foundation Year
Physics, part B
Physics project (parts of the course)
Engineering programmes
Electrical engineering
Electrical engineering project
Telecommunication
Degree project in Earth and Space Sciences
Master of Engineering programmes, year 1–3
Bachelor’s thesis in Earth and Space Sciences
Electric circuits and electric power (part of the
course)
Engineering measurements (for Automation and
Mechatronics Engineering)
Engineering measurements (for Electrical
Engineering)
Environmental measurement techniques
High frequency electromagnetic waves
Planetary sciences
4
Master’s courses and equivalent
Active microwave circuits (parts of the course)
Astrophysical dynamics
Electromagnetic waves and components
Experimental physics: spectroscopic methods
(parts of the course)
Image processing
Galaxies and observational cosmology
Master’s thesis in Earth and Space Sciences
Microwave engineering (parts of the course)
Millimetre wave and THz technology
Modern astrophysics
Plasma physics with applications
Remote sensing
Radar systems and applications
Radioastronomical techniques and
interferometry
Satellite positioning
Satellite communications
Space science and techniques
Stellar physics
The interstellar medium and star formation
Bachelor’s Thesis Reports
Erik Hellsten, Markus Polleryd, David Svensson,
Emilio Jorge
Study of the correlation between oceanic wave
height and the power spectrum of microseismic
activity using artificial neural networks
(Supervisor: Hans-Georg Scherneck)
Frida Strömbeck, Alexander Bore, Charbel
Rizk, Calle Ekdahl
Simulation of cometary orbits in the Oort cloud
and in the proximity of planets
(Supervisor: Magnus Thomasson)
Mattias Sjöberg, Björnborg Nguyen, Henrik
Gårdh
Studying ash plumes with GNSS
(Supervisor: Rüdiger Haas and Johan Löfgren)
Master’s Thesis Reports
Elmin Tutkur
Wideband directional couplers and power splitters
(Examiner/Supervisor: Vincent Desmaris)
Gustav Samuelsson
Using Onsala’s LOFAR station to observe
exoplanets using beamlets
(Examiner/Supervisor: John Conway)
Saladin Grebovic
Gravitational instability of nearby galaxies:
dwarfs vs. spirals
(Examiner/Supervisor: Alessandro Romeo)
The photo shows the two halves of the Onsala LOFAR station. To the right, the 96 high-band
antennas in their protective ‘tiles’. To the left, the 96 low-band antennas.
Photo: Leif Helldner
5
me given
Master’s program
artment
by us and the Dep
hysics.
of Fundamental P
Master’s programme
PHYSiCS anD aSTronoMY
CarEEr oPPorTUniTiES
The skills in problem solving and advanced
experimental techniques, as well as collaboration
and presentation skills, acquired in this program are
highly valued both in the academic world and on the
job market.
From elementary particles to a complex universe
Understanding the basic laws of physics has been a fascinating
problem since the birth of modern science. It is of great intrinsic
interest and also forms the basis of other branches of science.
Trying to probe the smallest structures of matter and the largest
structures of the Universe also drives the development of new
technologies.
Physics and Astronomy is intended for students with a keen
interest in either the theoretical or experimental aspects of frontline physics and astronomy.
Previous students have found positions in for
example industrial research, consulting, product
and production development, management and
administration, financial analysis.
The interested student will also be well prepared
to enter a doctoral programme at Chalmers or at
another university in both Sweden and worldwide.
UniQUE FEaTUrES
Close connections to leading research laboratories
like the accelerator facilities at CERN and GSI, and
the Swedish National Facility for Radio Astronomy:
Onsala Space Observatory.
SPECiaLiZaTion
Through the choice of elective courses it is possible
to specialize in theoretical and/or experimental
aspects of particle physics, subatomic physics or
astrophysics.
Year 1
Quantum
Mechanics
Advanced
Quantum
Mechanics
Electrodynamics
Experimental
Modern
Physics:
Spectroscopic Astrophysics
Methods
Gravitation
and
Cosmology
Interstellar
Medium &
Star Format.
Quantum
Field Theory
Astroparticle
Physics
Advanced
Subatomic
Physics
Galaxies
& Observat.
Cosmology
Elective
courses
Elective
courses
Spring
Autumn
Year 2
Phys. Beyond
String
the Standard
Theory
Model
Modern
Subatomic Astrophysical
Dynamics
Detectors
Plasma
Physics
Elective
courses
Elective
courses
Master’s Thesis
30 or 60 Credits
Elective
courses
Autumn
Elective
courses
Spring
Semi-compulsory courses, select 4–8 of 12
The order of the courses might be changed.
The airborne radar system CARABAS
Orionnebulosan
6
Chalmers University of Technology, SE-412 96 Gothenburg, Sweden, Phone +46 31 772 10 00, chalmers.se
me given
Master’s program
artment
by us and the Dep
gy and
of Microtechnolo
Nanoscience.
Master’s programme
WirELESS, PHoToniCS anD
SPaCE EnGinEErinG
CarEEr oPPorTUniTiES
Diffractive optics
Photonics laboratory
GaN MMIC X-band transceiver fabricated at Chalmers
Electron beam lithography in
Chalmers clean room
Electromagnetic waves in research and everyday life
Wireless, Photonics and Space Engineering with their many
applications are large industries and strong research fields both
in Sweden and worldwide.
The master’s programme will prepare you for a career in this
field through studies of wireless and optical communication
components and systems, RF and microwave engineering,
photonics (phenomena and applications utilizing photons), and
space science and techniques.
The programme provides a master’s education for a
future career in engineering branches that rely heavily
on electromagnetic waves, e.g. telecommunication,
automotive electronics, space engineering,
medical applications of microwaves and photonics,
remote sensing, solid state lighting, environmental
monitoring, navigation, and radio astronomy.
You will find career opportunities in industry, at
universities, or at research institutes.
UniQUE FEaTUrES
The programme offers a unique opportunity to study
a combination of subjects where Chalmers has
world‐class facilities: Onsala Space Observatory
with radio telescopes and equipment to study the
Earth and its atmosphere, the Nanofabrication
Laboratory with a clean room for micro and
nanotechnology, and state‐of‐the‐art photonics and
microwave measurement equipment in research
laboratories.
CoUrSES
The programme starts with five compulsory courses.
Through semi-compulsory courses, students
can specialize in wireless, photonics or space
engineering, or a combination thereof. To provide
opportunities to study related fields, there is also a
wide range of elective courses.
Year 1
The research satellite Odin
Electromagnetic Waves
and
Components
Microwave
Engineering
Wireless and
Photonics
System
Engineering
Space
Science
and
Techniques
Antenna
Fundamentals Engineering
of
Photonics
Active Microwave Circuits
Autumn
Remote
Sensing
Laser
Engineering
Radar
Systems
and
Applications
Spring
Year 2
Design of
MMIC
Mm-wave &
THz Techn.
Optoelectronics
Fiber Optical
Communic.
Satellite
Communic.
Satellite
Positioning
Semiconduct.
Devices
Elective
courses
Spring
Elective
courses
Eleven feed antenna for radio telescopes
The airborne radar system CARABAS
Master’s Thesis
Semi-compulsary courses, select 3–7 of 12
7
Chalmers University of Technology, SE-412 96 Gothenburg, Sweden, Phone +46 31 772 10 00, chalmers.se
Doctoral Programme
Donal Murtagh, Deputy
Head of Department
and responsible for the
doctoral programme.
The doctoral programme is organised as three possible specialisations within the subject area of Radio
and Space Science. These specialisations are Astronomy, Environmental Science, and Electrical Engineering, reflecting the diversity of the research carried out at the department. The school strives to
give the students a thorough understanding of the research area they have chosen and in depth studies
in a particular subject with the aim of achieving Chalmers goals for post-graduate education. There are
currently about 34 research students in the programme - most of whom are employed by the department, although a handful have positions in industry or at other institutes. During the past year six PhD
degrees and six licentiate degrees have been awarded, while four new post-graduate students were
recruited.
We also strive to engage the PhD students in the department and
have organised a PhD-student forum in March. Here we discussed
such subjects as the results of the Personnel questionaire, Generic
and transferable skills courses and how to spread knowledge, such
as good programming among each other.
In his PhD work, Johan Löfgren, Space
Geodesy and Geodynamics, evaluated a new
tide gauge at the Onsala Space Observatory
that is based on reflected GNSS signals.
This installation uses signals from satellite
navigation systems like GPS to measure sea
level.
Licentiates
Taïssa Danilovich
Joachim Wiegert
Studies of the S-type AGB star
W Aquilae : The circumstellar
envelope and the fain companion
Extrasolar Kuiper and asteroid
belts Modelling far-infrared dust
emission
February
April
Supervisor: Kay Justtanont
Supervisor: René Liseau
Lukas Lindroos
Mitra Hajigholi
Stacking of interferometric
data at sub-millimeter and radio
wavelengths
Observations with Herschel:
High-mass star formation and
the search for NH+
March
June
Supervisor: John Conway
Supervisor: John Black
Eskil Varenius
8
Kazutoshi Sagi
High-resolution radio imaging of
galaxy nuclei
Analysis of stratospheric ozone
depletion in the Arctic using a
data assimilation technique
April
June
Supervisor: John Conway
Supervisor: Donal Murtagh
Doctoral Dissertations
Johan Löfgren
Marston Johnston
Local Sea Level Observations
Using Reflected GNSS Signals
Evaluating Tropical Uppertropospheric Water in Climate
Models Using Satellite Data
January
April
Supervisor: Rüdiger Haas
Supervisor: Patrick Eriksson
Santiago Arellano
Spaceborne Synthetic Aperture
Radar for Sea Ice Observations,
Concentration and Dynamics
Studies of Volcanic Plumes with
Remote Spectroscopic Sensing
Techniques -DOAS and FTIR
measurements on volcanoes of the
Network for Observation of Volcanic
and Atmospheric Change
February
October
Supervisor: Leif Eriksson
Supervisor: Bo Galle
Andreas Skyman
Maciej Soja
Gyrokinetic simulations of
turbulent transport in tokamak
plasmas
Modelling and Retrieval of Forest
Parameters from Synthetic
Aperture Radar Data.​
February
October
Supervisor: Hans Nordman
Supervisor: Lars Ulander
Anders Berg
In april our PhD student Sofia Wallström got a chance to fly with NASA’s airborne
observatory, appropriately named SOFIA (Stratospheric Observatory for Infrared Astronomy).
Sofia blogged about the experience on Chalmers website.
9
Advanced Receiver
Development
Research group leader
Victor Belitsky
Staff
Victor Belitsky
Vincent Desmaris
Andrey Ermakov
Sven-Erik Ferm
Mathias Fredrixon
Igor Lapkin
Denis Meledin
Alexey Pavolotsky
Magnus Strandberg
Erik Sundin
Mark Whale (-Nov)
Doctoral students
Parisa Aghdam
Sascha Krause
Hawal Marouf Rashid
The Group for Advanced Receiver Development (GARD) is a research and engineering
group working on Terahertz technologies and instrumentation. GARD research activities
are focused on superconducting electronics, material science and thin-film processing.
The results and experience from the research facilitate development and building of
state-of-the-art instruments used in radio astronomy and environmental science.
Band 5 Full Production for ALMA
At the beginning of 2013, GARD was awarded
the contract to build the Band 5 receiver for the
entire Atacama large Millimeter/submillimeter
Array (ALMA) project in Chile. The Project aims
to produce in total 67 ALMA Band 5 receiver cartridges in collaboration between GARD and the
Nederlandse Onderzoekschool Voor Astronomie
(NOVA), The Netherlands, and is funded by the
European Southern Observatory at the level of
about 13 M€ for 5 years. The European consortium for full production of ALMA Band 5 also
collaborates with the National Radio Astronomy
Observatory (NRAO), USA, responsible for the
local oscillator system and the warm cartridge
assembly.
Atacama Path finder EXperiment (APEX)
GARD has performed a service mission to
upgrade cryogenic low-noise IF amplifiers of three
receiver channels on the Swedish Heterodyne
Facility Instrument, SHeFI, in the beginning of
2014.
Figure capture:
GARD members
M. Fredrixon, A.
Pavolotsky and D.
Meledin in action:
installation of the
Band 5 receiver
cartridge into the
cryostat.
10
During 2014, GARD continued to work on the
new generation Hot Electron Bolometer (HEB)
mixer of the APEX T2 receiver channel. As a part
of that activity GARD has developed technology
for deposition of ultra-thin NbN superconducting
films with record high critical temperature.
A huge interest in the ALMA Band 5 receiver
created an opportunity to install the preproduction receiver built under EC FP6 funded
project at the APEX telescope, in Chile. The
ALMA Band 5 covers the frequency range 163
GHz – 211 GHz. The para-H2O (313-220) line at
183 GHz lies in the middle of Band 5. It is one of a
few H2O lines that can be observed from Earth (at
the excellent APEX/ALMA site the transmission
can approach 50 % at the line peak). The band 5
receiver is planned to be installed on the APEX
telescope in February 2015.
New 2-channel MM-Wave Receiver for OSO
20m
GARD has designed and built the new 2-channel
receiver that has been installed and commissioned
at Onsala 20 m antenna. The work was done
in collaboration with the
electronic lab at the Onsala
site. The receiver covers two
bands: the 4 mm band where
state-of-the art amplifiers (from
the National Radio Astronomy
Observatory, USA) will be used
and the channel to be installed
during 2015 and the 3-mm band
with 2SB SIS mixers (from
Institut de Radioastronomie
Millimétrique (IRAM), France)
available for observations during
the 2014/2015 observational
season. The receiver has a very
compact design suitable for the
tight space of the Onsala 20 m
antenna cabin. GARD has made
a completely new optical design
for this receiver with a built-in
calibration for both channels and
an innovative fast optical switch
for on/off source observations.
Global Environmental
Measurements and
Modelling
Research group leader
Donal Murtagh
The Global Environmental Measurements and Modelling group focuses on the
production and interpretation of global datasets. To a large extent these originate
from the Swedish led Odin satellite project, where we are the main data processing
centre for the sub-mm radiometer instrument providing the atmospheric community
with quality assessed data. On the scientific side we have continued with studies
of the chemical and dynamical processes affecting the atmosphere. As in earlier
annual reports, we chose to highlight one or two aspects of this research each year.
Aerosol optics in chemical transport models
In recent years there has been an increased
interest in using satellite observations for
validating or constraining atmospheric chemical
transport models (CTMs). This development
has been stimulated by the growing importance
of hemispherical transport in air pollution
modelling. It has also been prompted by recent
trends of coupling CTMs to climate models in
order to obtain a better description of aerosolcloud interaction. To validate the description
of hemispheric transport and of climate effects
of air pollutants requires a stronger focus
on concentration fields aloft, where in situ
observations of chemical tracers are sparse. Many
studies on the use of satellite observations in
CTMs have focused on trace gases, and much
less on aerosols. A main difficulty in exploiting
satellite data of aerosols is to map the physical
and chemical properties of particles described in a
CTM to the optical properties retrieved from the
observations. The use of over-simplified aerosol
optics models in this mapping can introduce
additional errors that complicate the comparsions
between CTM results and satellite products.
Within the work performed in the VR-project
AGES (Aerosol optics in Global Earth-System
modelling) new aerosol optics models are being
developed that account for the complex aggregate
topology of externally mixed soot aggregates
as well as for internal mixing of chemically
heterogeneous aerosols, such as mixtures of
soot with sulphate and organic compounds.
00
5
t t
0
85
50
a
at
68
a
Lat
82
68
t 5 226
50
Morphology of a bare (top
left) and encapsulated soot
aggregate (bottom lef). AOD
computed with MATCH-SALSA
in conjunction with the new
aerosol optics model (right).
Comparisons with laboratory measurements
reveal that morphologically simple particle models
tend to underestimate the absorption cross section
and overestimate the single scattering albedo
of soot aerosols. The new optics model shows
considerably better agreement with laboratory
observations; it has now been implemented into
the Swedish CTM MATCH, which contains
the Finnish aerosol dynamics module SALSA.
The figure shows aerosol optical depth (AOD)
modelled with MATCH-SALSA in conjunction
with the new aerosol optics model. This work will
pave the way for validation of MATCH-SALSA
with MODIS AOD and Calipso profiles of the
aerosol backscattering coefficient.
Polar mesospheric clouds (pictured below) are clouds that
form in the summer polar mesopause, 80 km above the
surface. Using data from Odin we can see structures in
the clouds and background atmosphere that have not been
detectable by previous measurements.
0
8
6
80
5
0
2
0
11
Staff
Patrick Eriksson
Michael Kahnert
(adj. prof.)
Donal Murtagh
Kristell Perot
Joel Rasch
David Simpson
(adj. prof.)
Joachim Urban (-Aug)
Doctoral students
Emma Andersson
Ole Martin Christensen
Maryam Khosravi (-Feb)
Kazutoshi Sagi
Optical Remote Sensing
Research group leader
Bo Galle
Staff
Johan Ekholm
Bo Galle
Johan Mellqvist
Santiago Arellano (Nov-)
Doctoral students
Santiago Arellano (-Oct)
Jörg Beecken
Vladimir Conde
John Johansson
The optical remote sensing group is working with
development and application of ground-based
optical remote sensing methods for atmospheric
measurements. In specific we are focusing on
tailoring instruments and measurement strategies
to address specific measurement problems related
to environmental research and monitoring needs.
The work is very international and field oriented,
and spans a large variety of disciplines.
Volcanic gas measurements
Since 2001 we are strongly involved in developing
methods to quantify gas emission from active
volcanoes. The EU-project NOVAC (Network
for Observation of Volcanic and Atmospheric
Change), coordinated by Chalmers, was initiated
in fall 2005. This project aims at establishing a
network of instruments for gas measurements and
today comprises 27 of the most active volcanoes in
the world. In 2013 a new project DECADE (Deep
Earth Carbon Degassing) was initiated, aiming at
improving the knowledge on CO2 emission from
volcanoes as part of a large scale international
effort DCO, Deep Carbon Observatory. During
2014 we have also made significant efforts in
the EU-project FUTUREVOLC on Iceland, in
specific in relation to the volcanic fissure eruption
at Holuhraun yielding SO2 emissions exceeding
50 000 ton/day. During the year fieldwork
has been carried out on volcanoes in Iceland,
Nicaragua, Costa Rica, Colombia, Chile and D.R.
Congo.
Industrial hydrocarbon emissions
Emissions of hydrocarbons from oil related
industrial activities constitute an important
environmental problem. We have developed
optical methods for quantification of emissions of
The Navajo Piper aircraft that has been
equipped with custom made monitoring
instruments for measuring exhaust plumes of
ships. The installation has been certified by
the European Air Safety Agency. Photo: Tue
Friis-Hansen
hydrocarbons, NO2 , SO2 and we are involved in
joint European work, CEN WG 38, to standardize
these techniques. We participated in the NASA
Discover AQ project in Houston in 2013 and
during 2014 we have been working on these data
to compare the measurements with similar ones
carried out from airplanes and ground sites.
Emissions from ships
A method, for remote airborne and ground based
measurements of exhaust gas emissions from
ships has been developed. The aim with this
system is to be able to control whether ships obey
new environmental regulation within EU and
the international maritime organization, IMO.
During 2013 and 2014 the system was rebuilt into
a Navajo Piper aircraft and then the installation
was certified by the European Air Safety Agency.
Another system has been operating from an
island in the inlet of Gothenburg and more
than 4000 ships were measured during 2014. In
addition we participated in a joint ship emission
campaign in Gothenburg in October 2014.
Stratospheric ozone depletion and satellite
validation
Since 1994 we are operating a high resolution
FTIR for solar spectroscopy at Harestua in
southern Norway. The instrument is part
of NDACC (Network for the Detection of
Atmospheric Composition Change), and its
main purpose is to study the composition of
the atmosphere in relation to climate gases and
to gases that induce stratospheric ozone loss.
During 2014 regular measurements have been
carried out, financed by Swedish environmental
protection agency.
Volcanic fissure eruption at Holuhraun on Iceland,
September 2014. Photo: Vladimir Conde
12
Plasma Physics and
Fusion Energy
The group is focused on theoretical research on turbulent transport, magnetohydrodynamic
(MHD) stability, and energetic particle physics of burning fusion plasmas. The research is strongly
integrated with the international research activities, in particular the EU and ITER program, for
the realisation of fusion energy as a safe, clean, and sustainable energy source. In addition to the
topical areas detailed below, the group is also promoting these research areas in the Integrated
Tokamak modelling programme on the European level.
Turbulent transport and MHD stability
The strong gradients in temperature present
in tokamak fusion plasmas provide a source of
free energy that feeds instabilities over a wide
range of sizes and frequencies. These small
scale instabilities in turn drive turbulence which
results in large transport of heat and particles
across the confining magnetic field. The large
turbulent transport crucially affects the size and
performance of a fusion device. Our current work
is focused on realistic large scale gyrokinetic
turbulence simulations of the new ITER-like
wall experiments at the Joint European Torus
(JET), and further theoretical developments of a
computationally efficient fluid model for turbulent
transport that is more suitable for regular use in
analysis and predictions of experiments.
The global MHD pressure stability limit is one of
the important parameters defining operational
space of a fusion device. A pressure limit is set
by the ideal kink mode growing on the Alfvén
time scale (in the range of microseconds). In
the presence of conducting structures or due to
interaction of the mode with plasma particles
(kinetic effects), the mode growth could be
reduced allowing subsequent mode control
or be completely stabilized making operation
space wider. Our activity in this field of research
is focused on the stability limit studies at the
ASDEX Upgrade device. Experimental results are
compared to the numerical simulations with the
final aim of predicting pressure stability limits for
the future generation of fusion devices.
Energetic particle physics
One important objective for the next generation
tokamak ITER is the study of alpha particle
production, confinement and consequent heating
of the main plasma. In fact, energetic particles
constitute the only heating alternative beyond
the Ohmic regime, but are also known to play a
decisive role for plasma stability. For example
the presence of fast ions in the plasma core
significantly tranquilizes the often-observed
sawtooth oscillations in the plasma electron
temperature, leading to sawteeth-free periods
pertaining as long as a second. On the other
hand, fast particles are prone to excite wave
instabilities in the Alfvénic frequency range,
which may subsequently lead to severely degraded
alpha particle confinement and heating. Within
this field, our research activity focuses on theory
development and modeling of nonlinear waveparticle interaction, which is motivated by the
need to assess the implications of Alfvénic
activity on burning plasma scenarios and may
further provide highly desired opportunities
to extract information on the inhospitable
plasma core via comparison with diagnostic
measurements.
Recent modeling results of a kinetic resonance (a) that
show how the formation of so called holes and clumps
in the phase space density of fast particles is preceded
by the establishment of a nearly unmodulated plateau
(b), from which the structures eventually detach (c).
(c)
(a)
(b)
13
Research group leader
Hans Nordman
Staff
Dan Andersson (prof.
emeritus)
Luis Fazendeiro (-Jan)
Yueqiang Liu
(adj. prof.)
Hans Nordman
Robert Nyqvist
Ola Olsson (Aug-)
Eva Palmberg (lecturer
emeritus)
Pär Strand
Doctoral students
Frida Håkansson
Andreas Skyman (-Sep)
Daniel Tegnered
Radar Remote Sensing
Research group leader
Leif Eriksson
Staff
Jan Askne (prof. emeritus)
Anders Berg (Apr-)
Erik Blomberg (-Jun)
Gisela Carvajal
Leif Eriksson
Malin Johansson
Maciej Soja (Dec-)
Lars Ulander
Doctoral students
Wiebke Aldenhoff (Oct-)
Anders Berg (-Mar)
Erik Blomberg (Jul-)
Maciej Soja (-Nov)
Jan Torgrimsson
The objective of our research is to develop and understand advanced radar methods and their
application in forestry, glaciology and oceanography. The group specialises in synthetic aperture
radar (SAR) and develops algorithms for SAR image formation including autofocus. Large-scale
forest mapping is an important application motivated by the need for improved climate change
prediction, storm-damage mitigation and sustainable management in commercial forestry. Ocean
surface winds and currents, and sea ice are other applications with importance for the climate
system, but also for support to ship routing and other maritime activities.
Sea ice mapping with interferometric SAR
In 2014 the group carried out an unusual study
on the land-fast sea ice in the northern Baltic Sea.
Using the Italian satellite constellation known
as Cosmo-SkyMed, two pairs of SAR images
with metre-resolution were acquired over the
same area at the coastal border of Finland and
Sweden. The images were processed to produce
interferograms showing the small-scale (cm-mm
range) movements and deformation that took
place during the 24 hours between the satellite
overpasses. The radar technique, known as
Interferometric SAR, or InSAR, was also used to
study regional variations in the coherence over
the ice. Loss in coherence could be attributed
to temporal effects such as temperature change,
movement of the ice and snowfall. The low
coherence of the open water channels filled with
brash ice made it possible to separate them from
the refrozen leads. Fringe patterns indicated
deformation due to thermal ice expansion and
grounded ice ridges. Large deformation could be
observed closer to the fast ice edge, where the
drifting pack ice appeared to exert pressure on the
fast ice, and around leads and rocky islands.
42
48
’
30
’
Forest mapping with interferometric SAR
The InSAR technique was also used by the group
to estimate forest parameters. The TanDEM-X
system, deployed by the German Aerospace
Center in June 2010, consists of two SAR
satellites in a tight tandem formation, with only
a few hundred metres distance in the operational
phase. The formation flying significantly reduces
the coherence loss due to temporal changes
between acquisitions. The SAR system operates
at X-band, i.e., with a 3 centimetre wavelength,
and has a high a spatial resolution (ca. 1 m) which
makes it useful for mapping of tree canopies.
The group has developed a interferometric
model (two-level model, TLM), in which forest
is represented by two discrete scattering levels,
ground and vegetation including gaps. It has been
shown that direct inversion of TLM provides
estimates of forest height and canopy density,
without the need for reference data. A biomass
model has also been developed, in which the
above-ground biomass is estimated from the
TLM inversion products. Future work will include
extension to regional- and national-level mapping
using the National Forest Inventory (NFI) data
base.
’
N
6
36 5 oN
.00
’
45
30 ’
’
24
’
24 o
E
Fast ice edge
15
’
0
30
’
5
10
km
4
5’
Two-pass SAR interferometry was used to map surface
movements of the sea ice in the northern Bay of Bothnia.
The gray area is decorrelated, whereas one colour cycle
corresponds to a differential movement in the radar lineof-sight direction of 1.56 cm over 24 hours.
14
Using the single-pass interferometric SAR system
TanDEM-X together with a high-resolution digital terrain
model and the new interferometric two-level model,
forests can be mapped in terms of forest height, canopy
density, and biomass with good accuracy, as it has been
shown for the test site of Remningstorp, situated in the
province of Västergötland, just 10 km north-east of Skara.
Space Geodesy and
Geodynamics
Our main interests are geodynamic phenomena and atmospheric processes. We study e.g.
deformations of the Earth’s crust due to mass redistribution, inter- and intra-plate tectonics,
loading effects, and variations in the Earth’s orientation and rotation. We also study spatial
and temporal variations of water vapour in the atmosphere. We address these research
topics using a variety of observational techniques together with theoretical modelling.
Research group leader
Rüdiger Haas
Multi-GNSS-R for sea-level monitoring
In January, Johan Löfgren successfully defended
his PhD thesis. He investigated the use of
reflected Global Navigation Satellite System
(GNSS) signals from different satellite systems,
i.e., multi-GNSS, to monitor the local sea level.
The work mainly focused on the GNSS tide gauge
at the Onsala site, which has been operated since
2011. Two complementing analysis strategies were
used to derive local sea level with commercial
geodetic GNSS equipment. Time series of the
resulting GNSS-derived sea level were compared
with results from co-located traditional tide
gauges. Johan proved that the variations in the
sea level estimated from the GNSS data, gave
high correlations (up to 0.97) and low standard
deviations (3–4 cm) compared to the results from
traditional techniques. The advantage of this
novel sea level monitoring technique is that one
instrument can measure both land motion and
sea level motion, either separate or together. By
combining these two measurements, it is possible
to measure the absolute sea level, i.e., the sea
level with respect to the International Terrestrial
Reference Frame.
A GPS-derived localtie vector at Onsala
A sketch of the instrumentation used to derive the
local-tie vector at Onsala from GPS measurements. Two
gimbal-mounted GNSS antennas are installed on the rim
of the 20 m telescope. The local-tie vector between the
reference points of the 20 m telescope and the ONSA
GNSS monument is derived from the analysis of semikinematic and/or kinematic GPS observations.
GPS data recorded with
two GNSS receivers,
mounted on the 20 m
telescope (see figure),
were analyzed to derive the so-called local-tie
vector between the reference point of the 20
m telescope and the Onsala GNSS monument.
Several observation campaigns were analyzed,
both semi-kinematic and kinematic ones. The
recorded data were analyzed together with
GPS data from the GNSS station ONSA with
an in-house developed Matlab-based software
package. The results obtained from the analysis
gave sub-millimetre standard deviations for the
horizontal components of the local-tie vector
while a slightly larger standard deviation was
obtained for the vertical component. The project
shows that it is possible to monitor the localtie vector during telescope operations with an
accuracy of a few millimetres. Compared to the
classical geodetic measurements, this approach is
less time consuming and significantly reduces the
workload.
Nordic Geodetic Commission (NKG) General
Assembly 2014
Sea level derived from the GNSS tide gauge at the Onsala
site during 20 days in 2012 (Oct. 9 to 29). From top to bottom
the sea level times series are derived from: GPS phase (L1),
GLONASS phase (L1), GPS and GLONASS phase (L1), GPS
SNR (L1), GLONASS SNR (L1), GPS phase (L2), GLONASS
phase (L2), GPS and GLONASS phase (L2), GPS SNR (L2)
and GLONASS SNR (L2). Each time series is paired with the
independent sea level observations from the co-located tide gauge
(black line). A mean is removed from each time series and the
pairs are displayed with an offset of 40 cm to improve visibility.
In September, Jan Johansson together with the
Swedish National Land Survey organized the
General Assembly of the NKG at Chalmers.
The conference had more than 120 international
participants and lasted for four days, including
a joint seminar of the NKG, the Nordic
Institute of Navigation, and the Swedish
“Radionavigeringsnämnden” on high accuracy
positioning and navigation.
15
Staff
Gunnar Elgered
Rüdiger Haas
Thomas Hobiger (Aug–)
Jan Johansson (adj. prof.)
Johan Löfgren (Feb–)
Tong Ning (–Jun)
Hans-Georg Scherneck
Doctoral students
Susana Garcia-Espada
(industrial student)
Johan Löfgren (–Jan)
Niko Petteri Kareinen
Radio Astronomy
and Astrophysics
Research group leader
Susanne Aalto
Staff
Susanne Aalto
Arnold van Ardenne
(adj. prof.)
Per Bjerkeli
John Black
Roy Booth (prof. emeritus)
Guillaume Drouart
Lulu Fan
Arto Heikkilä
Åke Hjalmarson
(prof. emeritus)
Cathy Horellou
Kay Justtanont
Kirsten Kraiberg Knudsen
René Liseau
Tuomas Lunttila
Matthias Maercker (Sep-)
Eamon O’Gorman (Jun-)
Hans Olofsson
Carina Persson
Glenn Persson
Alessandro Romeo
Gustaf Rydbeck
(prof. emeritus)
Magnus Thomasson
Karl Torstensson (-Oct)
Wouter Vlemmings
Anders Winnberg
(prof. emeritus)
Eva Wirström
Doctoral students
Daria Dall’Olio (Sep-)
Taïssa Danilovich
Niklas Falstad
Judit Fogasy
Mitra Hajigholi
Lukas Lindroos
Maryam Saberi (Jun-)
Eskil Varenius
Sofia Wallström
Joachim Wiegert
Our research covers a wide range of topics from planetary atmospheres, through the
early evolution of stars and planets, to late stages of stellar evolution, the physics and
chemistry of interstellar and intergalactic matter, the structure and evolution of galaxies,
and cosmology. We carry out observations both at radio frequencies and in other parts of
the spectrum. We do theoretical research and develop numerical simulations and models
of complex systems like galaxies and gas clouds and help to develop future telescopes
on the ground and in space. Here we present a few examples of the groups very recent
results.
The interstellar medium and star formation
As a result from the last month of Herschel Space
Observatory observations we made a unique
detection of gaseous water in the dark interstellar
cloud Barnard 5 where the temperature is only
10 degrees above absolute zero. Normally water
would only exist in the form of ice layers on dust
grains in such an environment, more than 0.5 pc
away from the nearest protostar, but the observed
amount of water as compared to methanol
indicates that the uppermost layers of ice are
contributing to the gas-phase composition via nonthermal desorption.
For the first time we have detected absorption of
the [N II] 205 μm line by extended low-density
foreground material towards bright far-infrared
background continuum sources. We attribute this
absorption to the warm ionised medium (WIM).
The detection points to a low WIM density
(0.1–0.3 cm-3) and a high filling factor (0.4-0.7)
in our Galaxy. The detection of the 205 μm line in
absorption offers a new tool for investigation of
the WIM and star forming regions. We have also
investigated the interstellar nitrogen chemistry
both theoretically and observationally by deep
searches for the so far undetected key molecule,
NH+, establishing low upper limits constraining
chemical models for dense and diffuse interstellar
gas.
Evolved stars
Using the large global VLBI network, including
our own Onsala 25 m telescope, it has been
possible to produce one of the deepest images
of a globular cluster (M15). The observations
revealed a number of the expected pulsars, and the
high angular resolution observations allowed for
accurate astrometry to determine the motions of
the pulsars through the cluster. The binary pulsar
M15C disappeared during our observations, as
expected when precession moves the pulsar beam
away from our line of sight. However, we noted
that the pulsar reappeared a few months later
instead of after the expected few hundred years.
This shows that pulsar beams must have a complex
emission pattern.
VY Canis Majoris is an extreme red supergiant
and with a radius of 1400 times that of the Sun,
and is one of the largest known stars in the Galaxy.
It is a highly evolved star and is currently losing
extreme amounts of mass to the interstellar
medium, creating a dense and dusty circumstellar
environment in its wake. We used the high spatial
resolution provided by ALMA (Atacama Large
Millimeter Array) to image this dust very close to
the star and found that dust with a mass of about
100 Earth masses had been created in the last few
decades alone. This dust was found to be located
along two main directions, and not at random
locations, in contradiction with current theories of
mass loss in red supergiants.
K km/s
Galaxy nuclei and their winds
With ALMA and SMA (Submillimeter Array)
observations of the luminous merger NGC3256
we have discovered two powerful bipolar
arcsec
16
Figure 1: Left: Methanol emission map of Barnard 5 from the
ARO 12 m telescope. Red and blue arrows show the direction
of outflows from the IRS 1 protostar, while white circles show
size and position of the Herschel beam. Right: Spectra observed
toward the northern methanol peak. The lower panel shows the
self-absorbed water detection. SO and C18O were observed
with the Onsala 20 m telescope.
molecular outflows – one from each nucleus.
One is part of a starburst-driven superwind seen
nearly pole-on. The molecular outflow from the
southern nucleus is a highly collimated bipolar jet
seen nearly edge-on. Outflow velocities are very
high: 1000-2000 km/s. With ALMA we have also
discovered a molecular outflow from the Seyfert
galaxy NGC1068 where the gas seems to be driven
out by the AGN (Active Galactic Nucleus). The
feedback from nuclear activity through molecular
outflows is significant in the gas consumption with
short gas depletion times, and hence evolution, of
these systems.
We are also using ALMA, IRAM and Herschel to
study the properties of the obscured nuclei that
in some cases are also driving these spectacular
outflows and winds. One example includes the
quasar Mrk231 where we find OH, H2O, CO and
HCN emission in the outflow and where we use
vibrationally excited (through the absorption of
mid-infrared photons) HCN to probe the dusty,
warped inner region. Recent Herschel results on
the luminous galaxy Zw049.057 reveal very high
H2O abundances in the central region where H2
column densities are extremely large resulting
in the core being invisible in many wavelengths
- even in X-rays. In addition we find that gas is
infalling onto the central region very likely feeding
the nuclear activity.
The high redshift Universe
Cosmologically distant galaxies of different
types represent galaxy evolution in a variety of
conditions. We study these both observationally
and theoretially using state-of-the-art facilities and
multi-wavelength data.
Gravitational instabilities play a primary role in
shaping the clumpy structure and powering the
star formation activity of gas-rich high-redshift
galaxies. In a theoretical analysis of the stability,
we have showed that scaling relations for mass-size
and linewidth-size can have a strong impact on the
size and mass of star-forming clumps, as well as on
the stability properties of the disc at all observable
scales. This makes the classical Toomre parameter
Figure 2: ALMA map of the CO 3-2 emission the active
galaxy NGC1068. The CO is tracing the molecular gas with
unprecedented resolution and sensitivity revealing individual
cloud complexes in and between the spiral arms. Bright nuclear
emission is linked to feeding of the supermassive black hole and
a powerful molecular outflow.
Figure 3: A false color Hubble
Space Telescope near
infrared image of VY CMa’s
circumstellar environment is
shown along with the new
ALMA data at 321 GHz (white
contours) and 658 GHz (black
contours). The expected
position of the star is labelled
‘VY’ while a massive dust
clump south-east of the star is
labelled ‘C’.
a highly unreliable indicator of gravitational
instability. Our work shows that multi-scale
observations are necessary to star formation and
disk-stability. Our prediction provide baseline to
future dedicated ALMA surveys.
To search for the light from distant galaxies that
are too faint to be individually detected, we
have developed and investigated a new stacking
algorithm for radio interferometric data. Our new
algorithm makes it possible to do a robust stacking
directly on the visibilities. The algorithm and
tool has received important attention from other
international research teams and has potential to
impact studies beyond our research group.
Massive galaxy cluster amplify the light of faint
background sources. In our multiwavelength study
of the MS0451-0305 cluster, CO(3-2) emission
line observations have revealed a very complex
structure of the z=2.9 multiply-image merging
system. Further using LABOCA and APEX,
our initial observations of the ‘El Gordo’ galaxy
cluster show detections of lensed submm galaxies.
Also, we are preparing for upcoming high angular
resolution JVLA observations of the individual
giant molecular clouds in a very strongly lensed
SMG.
In a comparative study of the morphologies of
AGN host galaxies and non-active galaxies, we
have investigated if major mergers can be the main
mechanism for triggering AGN activity. We took
the comprehensive structural and morphological
analyses of X-ray-selected AGN host galaxies
in the Cosmic Assembly Near-infrared Deep
Extragalactic Legacy Survey-Cosmic Evolution
Survey (CANDELS-COSMOS) field using HST/
WFC3 H-band imaging at 1 < z < 3.Combining
with the previous results, we can conclude that
X-ray selected AGNs at z<3 show no difference
in morphologies compared to non-active galaxies.
Major merger may be not important in triggering
this type of AGNs activities.
17
Onsala Space Observatory
Director
John Conway
Onsala Space Observatory (OSO) is the Swedish National Facility for Radio Astronomy.
In Onsala, the observatory operates two parabolic radio telescopes, a 25 m diameter
cm-wave dish and a 20 m diameter mm-wave dish, and the Swedish LOFAR (Low
Frequency Array) station. The observatory is also one of three partners in the Atacama
Pathfinder Experiment (APEX), a 12 m diameter submillimetre-wave telescope in Chile,
and provides the channel through which Sweden is involved in large international radio
astronomy projects, such as EVN (European VLBI Network), LOFAR, ALMA (Atacama
Large Millimeter/submillimeter Array), and SKA (Square Kilometre Array).
In addition to radio astronomy, geoscience activities are an official part of the mission
of the observatory. The geoscience equipment consists of receivers for GNSS
(Global Navigation Satellite Systems), several tide gauge sensors, a superconducting
gravimeter, a seismometer (owned by Uppsala University), and radiometers for
aeronomy. The 20 m telescope is partly used for geodetic VLBI (Very Long Baseline
Interferometry). The observatory also contributes to establishing the official Swedish
time, by hosting two hydrogen maser clocks and one cesium clock.
The 20 m telescope
The radome protecting the 20 m diameter
telescope in Onsala was upgraded in 2014. The
old radome had started showing wear and tear,
and it had become necessary to replace it. All 620
triangular panels were replaced with new ones
in August and September. The upgrade marks
a new lease of life for the telescope, which has
contributed to the research since 1976.
Staff
Per Bergman
Bhushan Billade
Per Björklund
Tobia Carozzi
Simon Casey
John Conway
Robert Cumming
Elvire De Beck (Sep-)
Lars Eriksson
Jonas Flygare (Oct-)
Peter Forkman
Roger Hammargren
Leif Helldner
Christer Hermansson
Karl-Åke Johansson
Jan Karaskuru
Ulf Kylenfall
Mikael Lerner
Michael Lindqvist
Iván Martí-Vidal
Mathias Maercker (MarAug)
Sebastien Muller
Michael Olberg
Henrik Olofsson
Miroslav Pantaleev
Lars Pettersson
Lars Wennerbäck
Ronny Wingdén
A new receiver for the 3 mm band, 85–116 GHz,
was installed in March 2014. This receiver is dual
polarisation sideband separating, each sideband
having a bandwidth of 4 GHz. The receiver
temperature is approximately 50–60 K (singlesideband), and the baseline stability is much better
than with the receiver it replaced.
The number of proposals for single-dish
astronomical observations with the telescope
increased substantially in 2014, with both galactic
and extragalactic observations proposed. The 20
m telescope is also used for VLBI observations by
the astronomical and geodetical communities.
The 25 m telescope and VLBI
The 25 m diameter telescope in
Onsala celebrated its 50th birthday
on 26 November 2014. Since 1964,
the telescope has observed the
universe. One of its most important
discoveries came in 1973, when it was
the first telescope in the world to find
The most spectacular event during the
upgrade of the 20 m telescope radome was
the replacement of the 50 panels forming
the cap of the radome. The new panels
were lifted in place with a 54 meter high
crane. Photo: Lars Wennerbäck
18
evidence of the CH molecule in space – a radical
which has an important role in the chemistry
of the interstellar medium. As early as 1968,
the telescope took part in the first transatlantic
VLBI measurements. In 2004, a new optical
fibre network was installed and the telescope
participated in the first e-VLBI experiments.
Today, the 25 m telescope continues to participate
in VLBI observations of stars and distant
galaxies, mainly within the European VLBI
Network (EVN).
Two results from VLBI observations, including
the Onsala 25 m telescope and made by teams
with Onsala astronomers, are good examples of
the power of VLBI: EVN observations pinpointed
the locations where the nova V959 Mon emitted
gamma rays. The discovery revealed a probable
mechanism for the gamma-ray emissions, which
mystified astronomers when first observed in
2012. EVN observations of supernova 2014J in
the galaxy Messier 82, together with other data,
showed that the merger of two white dwarf stars
is by far the most likely cause for this Type Ia
supernova, and ruled out other models.
The Onsala Twin Telescope
Preparations for the installation of two new
radio telescopes, for geodetic VLBI, continued
during 2014. The procurement process was
finished, and the two 13.2 m diameter telescopes
have been ordered. It is expected that the first
test observations with the new telescopes, the
Onsala Twin Telescope (OTT), will begin in
2016. The OTT will follow the new international
VGOS (VLBI Geodetic Observing System)
recommendations, and lead to improved
measurement accuracy: 1 mm for station position
and 0.1 mm/yr for station velocity.
SKA
The Square Kilometre Array (SKA) project is now
in its design phase. Chalmers and Onsala Space
Observatory are part of two design consortia
which started their work in 2014. The Wide-band
Single Pixel Feeds (WBSPF) consortium, led
by OSO, is developing and testing technology
which enables dish antennas to be sensitive to a
much broader frequency range than in today’s
telescopes. Chalmers is one of the six institutes in
the WBSPF consortium. OSO is also a member of
the Dish consortium, within which it is designing
the 350–1050 MHz receiver for SKA.
Other activities in Onsala
Observations with the LOFAR station in
Onsala continued in 2014. LOFAR produces an
enormous amount of data; a new computer for
recording data locally (during 48 h) was installed
in 2014. The first referred paper presenting
images using international LOFAR observations
(of the starburst galaxy M82) led by Chalmers
astronomers was accepted for publication.
The outreach activities have continued, with,
e.g., school classes and other groups visiting the
observatory, as described on page 24 in this report.
APEX
The Supercam visiting instrument was successfully
installed in the Cassegrain cabin of APEX in
the autumn of 2014. Supercam is a 64-pixel 345
GHz heterodyne array built by the University of
Arizona. It is by far the largest such array, and
allows wide areas to be mapped in the CO(32) line. Making use of the optimal atmospheric
transparency at Chajnantor, Supercam will map
several extended regions such as the Galactic
Plane, the Magellanic Clouds and the Orion star
forming region.
ALMA image of the Mira binary star, with the heart shaped
bubble. The Nordic ALMA Regional Centre node in
Onsala assisted with the analysis of the data, and several
Chalmers astronomers participated in the project.
also the newly installed SuperCam array was
used, as were the bolometer cameras LABOCA
and ArTeMiS. Like previous years, the projects
covered a wide range of research topics, e.g.,
comets, star and planet formation, the interstellar
medium, evolved stars, and both nearby and highredshift galaxies. At least 74 refereed papers based
on APEX data were published in 2014.
ALMA
The Nordic ARC node based at OSO has been
in great demand during 2014 to assist Nordic
users of ALMA and is heavily involved in
the European verification of results from the
telescope.
ALMA observations of evolved stars continue
to deliver surprises. A spectacular heart shaped
bubble was revealed in the CO molecular
envelope of the Mira binary pair. The existence of
this bubble proves that a tenuous, but fast, wind is
blown from the companion (Mira B), cementing
its debated nature as a white dwarf. Additionally,
the CO line also reveals the expected spiral
structure arising from the binary interaction.
More than 50 projects were observed at APEX
during Swedish time in 2014. The principal
investigators of these projects were affiliated with
research organisations and universities in more
than 10 different countries. Most of the projects
used the SHFI heterodyne receiver, but of course
19
Staff shared with
research groups
Gunnar Elgered
Rüdiger Haas
Thomas Hobiger (Aug-)
Johan Löfgren (Sep-)
Tong Ning (-Jun)
Hans-Georg Scherneck
Magnus Thomasson
Karl Torstensson (-Dec)
Wouter Vlemmings
A majority of the Group
for Advanced Receiver
Development (p. 10)
is also part of the
observatory.
Preparations for the
two geodetic VLBI twin
telescopes. This is the site
for the northern telescope.
The site of the southern
telescope is just outside
this photo, to the right.
Publications
The list contains peer reviewed journal publications that were actually published during 2014. The
publications are presented for each research group and in alphabetical order based on the first
author´s last name. A few publications with authors from more than one research group are listed
in each group. In order to have a list of a reasonable size, we have chosen to only include peer
reviewed journal publications on these pages. PhD and licentiate theses are presented on pages
8 and 9. A complete list for 2014, and in most cases also links to the full papers, can be found at:
publications.lib.chalmers.se/cpl/lists/publications/departments.
Advanced Receiver Development
Billade, B.; Pavolotsky, A.; Belitsky, V. (2014).
Experimental Study of Frequency Multiplication in a Distributed
Array of SIS Junctions. IEEE Trans. THz Sci. Technol., 4, 254-259.
Hammar, A.; Whale, M.; Forsberg, P.; et al. (2014). Optical
Tolerance Analysis of the Multi-Beam Limb Viewing Instrument
STEAMR. IEEE Trans. THz Sci. Technol., 4, 714-721.
Krause, S.; Meledin, D.; Desmaris, V.; Pavolotsky, A.; Belitsky, V.;
et al. (2014). Epitaxial growth of ultra-thin NbN films on AlxGa1xN buffer-layers. Supercond. Sci. Tech. 27.
Rashid, H.; Meledin, D.; Desmaris, V.; Belitsky, V. (2014). Novel
Waveguide 3 dB Hybrid with Improved Amplitude Imbalance.
IEEE Microw. Compon. Lett., 24, 212-214.
Rashid, H.; Meledin, D.; Desmaris, V.; Pavolotsky, A.; Belitsky,
V. (2014). Superconducting 4-8-GHz Hybrid Assembly for 2SB
Cryogenic THz Receivers. IEEE Trans. THz Sci. Technol. 4,
193-200.
Pleijel, H.; Danielsson, H.; Simpson, D.; et al. (2014).Have
ozone effects on carbon sequestration been overestimated? A
new biomass response function for wheat. Biogeosciences., 11,
4521-4528.
Pérot, K.; Urban, J.; Murtagh, D.P. (2014). Unusually strong
nitric oxide descent in the Arctic middle atmosphere in early
2013 as observed by Odin/SMR.Atmos. Chem. Phys., 14,
8009-8015.
Sagi, K.; Murtagh, D.P.; Urban, J.; et al. (2014). The use
of SMILES data to study ozone loss in the Arctic winter
2009/2010 and comparison with Odin/SMR data using
assimilation techniques. Atmos. Chem. Phys., 14, 12855-12869.
Simpson, D.; Andersson, C.; Christensen, J.H.; et al.
(2014). Impacts of climate and emission changes on nitrogen
deposition in Europe: a multi-model study.Atmos. Chem.
Phys., 14, 6995-7017.
Simpson, D.; Arneth, A.; Mills, G.; et al. (2014). Ozone - the
persistent menace; interactions with the N cycle and climate
change. Curr. Opin. Env. Sust. 9-10, 9-19, 2014.
Global Environmental Measurements
and Modelling
Stevens, M.H.; Lossow, S.; Siskind, D.E.; … ; Urban, J.;
Murtagh, D.P.; et al. (2014). Space shuttle exhaust plumes in
the lower thermosphere: Advective transport and diffusive
spreading. J. Atmos. Sol-Terr. Phy., 108, 50-60.
Eriksson, P.; Rydberg, B.; Sagawa, H.; Johnston, M.; et al.
(2014). Overview and sample applications of SMILES and
Odin-SMR retrievals of upper tropospheric humidity and cloud
ice mass. Atmos. Chem. Phys., 14, 12613-12629.
Urban, J.; Lossow, S.; Stiller, G.; et al. (2014). Another Drop
in Water Vapor. EOS, Trans. Am. Geophys. Union, 95, 245246.
Hassler, B.; Petropavlovskikh, I.; Staehelin, J.; … ; Urban, J.;
et al. (2014). Past changes in the vertical distribution of ozone Part 1: Measurement techniques; uncertainties and availability.
Atmos. Meas. Tech., 7, 1395-1427.
Wu, D.L.; Lambert, A.; Read, W.G.; Eriksson, P.; et al.
(2014). MLS and CALIOP Cloud Ice Measurements in the
Upper Troposphere: A Constraint from Microwave on Cloud
Microphysics. J. Appl. Meteorol. Climatol., 53, 157-165.
Hegglin, M.I.; Plummer, D.A.; Shepherd, T.G.; … ; Urban, J.;
et al. (2014). Vertical structure of stratospheric water vapour
trends derived from merged satellite data. Nat. Geosci., 7,
768-776.
Johnston, M.; Eliasson, S.; Eriksson, P.; et al. (2014).
Diagnosing the average spatio-temporal impact of convective
systems - Part 2: A model intercomparison using satellite data.
Atmos. Chem. Phys., 14, 8701-8721.
Optical Remote Sensing
Aiuppa, A.; Robidoux, P.; Tamburello, G.; Conde, V.;
Galle, B.; et al. (2014). Gas measurements from the Costa
Rica-Nicaragua volcanic segment suggest possible along-arc
variations in volcanic gas chemistry. Earth Planet. Sc. Lett.,
407, 134-147.
Karl, M.; Castell, N.; Simpson, D.; et al. (2014).Uncertainties
in assessing the environmental impact of amine emissions from
a CO2 capture plant. Atmos. Chem. Phys., 14, 8533-8557.
Beecken, J.; Mellqvist, J.; Salo; K.; Ekholm, J.; et al. (2014).
Airborne emission measurements of SO2; NOx and particles
from individual ships using a sniffer technique. Atmos. Meas.
Tech. 7, 1957-1968.
Kleinböhl, A.; Khosravi, M.; Urban, J.; et al. (2014).
Constraints for the photolysis rate and the equilibrium constant
of ClO-dimer from airborne and balloon-borne measurements
of chlorine compounds. J. Geophys. Res-Atmos., 119, 69166937.
Conde, V.; Robidoux, P.; Avard, G., Galle, B.; et al. (2014).
Measurements of volcanic SO2 and CO2 fluxes by combined
DOAS; Multi-GAS and FTIR observations: a case study from
Turrialba and Telica volcanoes. Int. J. Earth Sci., 103, 23352347.
Kylling, A.; Kahnert, M.; Lindqvist, H.; et al. (2014).Volcanic
ash infrared signature: porous non-spherical ash particle
shapes compared to homogeneous spherical ash particles.
Atmos. Meas. Tech., 7, 919-929.
Conde, V.; Bredemeyer, S.; Duarte, E.; … ; Galle, B.; et al.
(2014). SO2 degassing from Turrialba Volcano linked to seismic
signatures during the period 2008-2012. Int. J. Earth Sci., 103;
1983-1998.
Laeng, A.; Grabowski, U.; von Clarmann, T.; … ; Urban, J.;
et al. (2014). Validation of MIPAS IMK/IAA V5R_O3_224
ozone profiles. Atmos. Meas. Tech., 7, 3971-3987.
Geirsson, H.; Rodgers, M.; LaFemina, P.; … ; Conde,
V.; Nilsson, D.; Galle, B.; et al. (2014).Multidisciplinary
observations of the 2011 explosive eruption of Telica volcano;
Nicaragua: Implications for the dynamics of low-explosivity ash
eruptions. J. Volcanol. Geoth. Res., 271, 55-69.
Larsson, R.; Buehler, S.; Eriksson, P.; et al. (2014). A
treatment of the Zeeman effect using Stokes formalism and
its implementation in the Atmospheric Radiative Transfer
Simulator (ARTS). J. Quant. Spectrosc. Radiat. Transfer. 133,
445-453.
20
Johansson, J.; Mellqvist, J.; Samuelsson, J.; Offerle, B.; et al.
(2014). Emission measurements of alkenes; alkanes; SO2; and
NO2 from stationary sources in Southeast Texas over a 5 year
period using SOF and mobile DOAS. J. Geophys. Res-Atmos.,
119, 1973-1991.
Johansson, J.; Mellqvist, J.; Samuelsson, J.; Offerle, B.; et al.
(2014). Quantitative measurements and modeling of industrial
formaldehyde emissions in the Greater Houston area during
campaigns in 2009 and 2011. J. Geophys. Res-Atmos., 119, J.
Geophys. Res-Atmos 4303-4322.
Loov, J.; Alfoldy, B.; Gast, L.; ... ; Mellqvist, J.; Beecken,
J.; Berg, N.; et al. (2014). Field test of available methods to
measure remotely SOx and NOx emissions from ships. Atmos.
Meas. Tech., 7, 2597-2613.
Lubcke, P.; Bobrowski, N.; Arellano, S.; Galle, B.; et
al. (2014). BrO/SO2 molar ratios from scanning DOAS
measurements in the NOVAC network. Solid Earth, 5, 409424.
Saballos, J.; Conde, V.; Malservisi, R.; et al. (2014). Relatively
short-term correlation among deformation; degassing; and
seismicity: a case study from Concepcion volcano; Nicaragua.
B. Volcanol., 76.
Smets, B.; d’Oreye, N.; Kervyn, F.; … ; Arellano, S.; … ; Galle,
B.; ... ; Norman, P.; et al. (2014). Detailed multidisciplinary
monitoring reveals pre- and co-eruptive signals at Nyamulagira
volcano (North Kivu; Democratic Republic of Congo). B.
Volcanol., 76.
Plasma Physics and Fusion Energy
Anderson, J.; Kim, E.; Moradi., S. (2014). A fractional FokkerPlanck model for anomalous diffusion. Phys. Plasmas, 21.
Anderson, J.; Halpern, F.; Xanthopoulos, P.; et al. (2014).
Statistical analysis and modeling of intermittent transport
events in the tokamak scrape-off layer. Phys. Plasmas, 21,
122306.
Borgdorff, J.; Ben Belgacem, M.; Bona-Casas, C.; Fazendeiro,
L.; … ; Strand, P.; et al. (2014). Performance of distributed
multiscale simulations. Phil. Trans. R. Soc. A-Math. Phys. Eng.
Sci., 372.
Chapman, I.; Becoulet, M.; Bird, T.; … ; Yadykin, D.; et al.
(2014). Three-dimensional distortions of the tokamak plasma
boundary: boundary displacements in the presence of resonant
magnetic perturbations. Nucl. Fusion, 54, 083006.
Falchetto, G.; Coster, D.; Coelho, R.; … ; Strand, P.; et al.
(2014). The European Integrated Tokamak Modelling (ITM)
effort: achievements and first physics results. Nucl. Fusion vol.
54.
Lilley, M.; Nyqvist, R. (2014). Formation of Phase Space Holes
and Clumps. Phys. Rev. Lett., 112.
Semenov, V.; Rasch, J.; Rakova, E.; et al. (2014). General
Study of Multipactor Between Curved Metal Surfaces. IEEE T.
Plasma Sci., 42, 721-728.
Semenov, V.; Rakova, E.; Zharova, N.; Rasch, J.; Anderson,
D.; et al. (2014). Simple model of the rf noise generated by
multipacting electrons. J. Phys. D. Appl. Phys. 47.
Singh, R.; Jhang, H.; Kaw, P.; … ; Nordman, H.; et al. (2014).
A semi-analytic power balance model for low (L) to high (H)
mode transition power threshold. Phys. Plasmas, 21, 062503.
Skyman, A.; Fazendeiro, L.; Tegnered, D.; Nordman, H.;
Anderson, J.; Strand, P. (2014). Effects of the equilibrium
model on impurity transport in tokamaks. Nucl. Fusion, 54,
013009.
Radar Remote Sensing
Berg, A.; Eriksson, L.E.B. (2014). Investigation of a Hybrid
Algorithm for Sea Ice Drift Measurements Using Synthetic
Aperture Radar Images. IEEE Trans. Geosci. Remote Sens.,
52, 5023–5033.
Carvajal, G.; Eriksson, L.E.B.; Ulander, L.M.H. (2014).
Retrieval and Quality Assessment of Wind Velocity Vectors on
the Ocean with C-Band SAR. IEEE Trans. Geosci. Remote
Sens., 52, 2519-2537.
Sandberg, G.; Ulander, L.M.H.; Wallerman, J.; et al. (2014).
Measurements of Forest Biomass Change Using P-Band
Synthetic Aperture Radar Backscatter. IEEE Trans. Geosci.
Remote Sens., 52, 6047-6061.
Sjögren, T.K.; Vu, V.T.; Pettersson, M.I.; … ; Ulander,
L.M.H.; et al. (2014). Suppression of Clutter in Multichannel
SAR GMTI. IEEE Trans. Geosci. Remote Sens., 52, 40054013.
Torgrimsson, J.; Dammert, P.; Hellsten, H.; Ulander, L.M.H.
(2014). Factorized Geometrical Autofocus for Synthetic
Aperture Radar Processing. IEEE Trans. Geosci. Remote
Sens., 52, 6674-6687.
Radio Astronomy and Astrophysics and
the Swedish National Facility for Radio
Astronomy
Aleman, I.; Ueta, T.; Ladjal, D.; … ; Vlemmings, W., et al.
(2014). Herschel Planetary Nebula Survey (HerPlaNS) First
detection of OH+ in planetary nebulae. Astron. Astrophys.,
566.
Arroyo-Torres, B.; Marti-Vidal, I.; Marcaide, J.M.; et al.
(2014). VLTI/AMBER observations of cold giant stars:
atmospheric structures and fundamental parameters. Astron.
Astrophys., 566.
Azulay, R.; Guirado, J.; Márcaide, J.; Marti-Vidal, I.; et
al. (2014). Radio detection of the young binary HD 160934.
Astron. Astrophys., 561.
Billade, B.; Pavolotsky, A.; Belitsky, V. (2014). Experimental
Study of Frequency Multiplication in a Distributed Array of
SIS Junctions. IEEE Trans. THz Sci. Technol., 4, 254-259.
Bjerkeli, P.; Liseau, R.; Brinch, C.; … ; Black, J.H.; … ;
Justtanont, K.; et al. (2014). Resolving the shocked gas in HH
54 with Herschel. CO line mapping at high spatial and spectral
resolution. Astron. Astrophys., 571, A90, 1-6.
Calves, G.M.; Pogrebenko, S.V.; Cimo, G.; … ; Haas, R.; et
al. (2014). Observations and analysis of phase scintillation
of spacecraft signal on the interplanetary plasma. Astron.
Astrophys., 564.
Cataldi, G.; Brandeker, A.; Olofsson, G.; … ; Liseau, R.; et
al. (2014). Herschel/HIFI observations of ionised carbon in the
beta Pictoris debris disk. Astron. Astrophys., 563.
Cernicharo, J.; Teyssier, D.; Quintana-Lacaci, G.; … ; De
Beck, E.; et al. (2014). Discovery of time variation of the
intensity of molecular lines in IRC+10216 in the submillimeter
and far-infrared domains. Astrophys. J. Letters., 796.
Chen, J-H.; Goldsmith, P.F.; Viti, S.; … ; Black, J.H.; … ;
Hjalmarson, Å.; et al. (2014). HERSCHEL HIFI Observations
of O2 toward Orion: Special Conditions for Shock Enhanced
Emission. Astrophys. J., 793, 111.
Chomiuk, L.; Linford, J.D.; Yang, J.; et al. (2014). Binary
orbits as the driver of gamma-ray emission and mass ejection in
classical novae. Nature., 514, 339-342.
Skyman, A.; Tegnered, D.; Nordman, H.; Strand, P. (2014).
Gyrokinetic modelling of stationary electron and impurity
profiles in tokamaks. Phys. Plasmas, 21, 092305.
Cicone, C.; Maiolino, R.; Sturm, E.; ... ; Aalto, S.; et al. (2014).
Massive molecular outflows and evidence for AGN feedback
from CO observations. Astron. Astrophys., 562, 25.
Yadykin; D.; Gryaznevich; M.; Frasinetti; L. & Gerasimov;
S. (2014). Effect of the external helical fields on the plasma
boundary shape in JET. Nucl. Fusion, 54, 6.
Cormier, D.; Madden, S.C.; Lebouteiller, V.; … ; Aalto, S.;
Costagliola, F.; … ; Cumming, R.; et al. (2014). The molecular
gas reservoir of 6 low-metallicity galaxies from the Herschel
Dwarf Galaxy Survey A ground-based follow-up survey of
CO(1-0), CO(2-1), and CO(3-2). Astron. Astrophys., 564.
21
Coutens, A.; Vastel, C.; Hincelin, U.; … ; Persson, C.M.; et
al. (2014). Water deuterium fractionation in the high-mass
star-forming region G34.26+0.15 based on Herschel/HIFI data.
Mon. Not. R. Astron. Soc., 445, 1299-1313.
Khouri, T.; de Koter, A.; Decin, L; … ; Justtanont, K.; … ;
Maercker, M.; … ; Olofsson, H.; et al. (2014). The wind of
W Hydrae as seen by Herschel I. The CO envelope. Astron.
Astrophys., 561, A5.
Crockett, N.R.; Bergin, E.A.; Neill, J.L.; Black, J.H.; et al.
(2014). HERSCHEL Observations of Extra-Ordinary Sources:
H2S as a Probe of Dense Gas and Possibly Hidden Luminosity
toward the Orion KL Hot Core. Astrophys. J., 781, 114, 1-21.
Khouri, T.; de Koter, A.; Decin, L.; … ; Maercker, M.; … ;
Justtanont, K.; … ; Olofsson, H.; et al. (2014). The wind of W
Hydrae as seen by Herschel II. The molecular envelope of W
Hydrae. Astron. Astrophys., 570, A67.
Danilovich, T.; Bergman, P.; Justtanont, K.; … ; Maercker,
M.; Olofsson, H.; et al. (2014). Detailed modelling of the
circumstellar molecular line emission of the S-type AGB star
W Aquilae. Astron. Astrophys., 569, A76.
Kim, Y.H.; Fox, J.L.; Black, J.H.; et al. (2014). Hydrocarbon
ions in the lower ionosphere of Saturn. J. Geophys. Res.Space., 119, 384-395.
Decarli, R.; Smail, I.; Walter, F.; … ; Knudsen, K.K.;
Lindroos, L.; et al. (2014). An Alma Survey of Sub-Millimeter
Galaxies in the Extended Chandra Deep Field South: SubMillimeter Properties of Color-Selected Galaxies. Astrophys.
J., 780.
Desmurs, J.; Bujarrabal, V.; Lindqvist, M.; … ; Bergman, P.;
et al. (2014). SiO masers from AGB stars in the vibrationally
excited v=1, v=2, and v=3 states. Astron. Astrophys., 565.
Drouart, G.; De Breuck, C.; Vernet, J.; et al. (2014). Rapidly
growing black holes and host galaxies in the distant Universe
from the Herschel Radio Galaxy Evolution Project. Astron.
Astrophys., 566.
Ertel, S.; Marshall, J.P.; Augereau, J.C.; ... ; Liseau, R.; et
al. (2014). Potential multi-component structure of the debris
disk around HIP 17439 revealed by Herschel/DUNES. Astron.
Astrophys., 561, A114.
Fan, L.L.; Fang, G.W.; Chen, Y.; … ; Knudsen, K.K.; et al.
(2014). Structure and Morphology of X-ray-selected Active
Galactic Nucleus Hosts at 1 < z < 3 in the Candels-Cosmos
Field. Astrophys. J. Letters., 784, 5.
García-Burillo, S.; Combes, F.; Usero, A.; Aalto, S.; … ;
Costagliola, F.; … ; Muller, S.; et al. (2014). Molecular line
emission in NGC 1068 imaged with ALMA : I. An AGNdriven outflow in the dense molecular gas. Astron. Astrophys.,
567, 125.
Gonzalez-Alfonso, E.; Fischer, J.; Aalto, S.; Falstad,
N. (2014). Modeling the H2O submillimeter emission in
extragalactic sources. Astron. Astrophys., 567, A91.
Gonzalez-Alfonso, E.; Fischer, J.; Gracia-Carpio, J.; Falstad,
N.; … ; Aalto, S.; et al. (2014). The Mrk 231 molecular outflow
as seen in OH. Astron. Astrophys., 561, A27.
Kirsten, F.; Vlemmings, W.; Freire, P.; et al. (2014). Precision
astrometry of pulsars and other compact radio sources in the
globular cluster M15. Astron. Astrophys., 565.
Konig, S.; Aalto, S.; Lindroos, L.; Muller, S.; et al. (2014).
Molecular tendrils feeding star formation in the Eye of the
Medusa -- The Medusa merger in high resolution 12CO 2–1
maps. Astron. Astrophys., 569, A6.
Lis, D.C.; Schilke, P.; Bergin, E.A.; … ; Black, J.H.; et al.
(2014). Widespread Rotationally Hot Hydronium Ion in the
Galactic Interstellar Medium. Astrophys. J., 785, A135, 1-9.
Maercker, M.; Ramstedt, S.; Leal-Ferreira, M.L.; et al. (2014).
The detached dust shells around the carbon AGB stars R
Sculptoris and V644 Scorpii. Astron. Astrophys., 570, A101.
Mantz, A.B.; Abdulla, Z.; Carlstrom, J.E.; … ; Horellou, C.;
et al. (2014). The XXL Survey. V. Detection of the SunyaevZel’Dovich Effect of the Redshift 1.9 Galaxy Cluster XLSSU
J021744.1-034536 with Carma. Astrophys. J., 794.
Marti-Vidal, I.; Márcaide, J. (2014). Limit to the radio
emission from a putative central compact source in SN1993J â†.
Astron. Astrophys., 561.
Marti-Vidal, I.; Vlemmings, W.; Muller, S.; Casey, S. (2014).
UVMULTIFIT: A versatile tool for fitting astronomical radio
interferometric data. Astron. Astrophys., 563.
Molina, S.N.; Agudo, I.; Gomez, J.L.; … ; Marti-Vidal, I.; et
al. (2014). Evidence of internal rotation and a helical magnetic
field in the jet of the quasar NRAO 150. Astron. Astrophys.,
566.
Mookerjea, B.; Vastel, C.; Hassel, G.E.; … ; Black, J.H.; …
; Persson, C.M.; et al. (2014). Detection of a dense clump in a
filament interacting with W51e2. Astron. Astrophys., 566, A61,
1-11.
Greaves, J.S.; Sibthorpe, B.; Acke, B.; … ; Liseau, R.; et al.
(2014). Extreme Conditions in a Close Analog to the Young
Solar System: Herschel Observations of ∈ Eridani. Astrophys.
J. Letters., 791.
Morabito, L.K; Oonk, J.B.R.; Salgado, F.; … ; Conway, J.;
… ; Horellou, C.; … ; Marti-Vidal, I.; … ; Varenius, E.; et al.
(2014). Discovery of Carbon Radio Recombination Lines in
M82. Astrophys. J. Letters., 795, L33.
Greve, T.R.; Leonidaki, I.; Xilouris, E.M.; … ; Aalto, S.; et al.
(2014). Star Formation Relations and CO-Spectral Line Energy
Distributions Across the J-Ladder and Redshift. Astrophys. J.,
794, 142.
Morosan, D.E.; Gallagher, P.T.; Zucca, P.; … ; Conway, J.; et
al. (2014). LOFAR tied-array imaging of Type III solar radio
bursts. Astron. Astrophys., 568, A67.
Henkel, C.; Asiri, H.; Ao, Y.; Aalto, S.; et al. (2014). Carbon
and oxygen isotope ratios in starburst galaxies: New data
from NGC 253 and Mrk 231 and their implications. Astron.
Astrophys., 565.
Higgins, R.; Teyssier, D.; Borys, C.; … ; Olberg, M.; et
al. (2014). The effect of sideband ratio on line intensity for
Herschel/HIFI. Exp. Astron., 37, 433-452.
Horellou, C.; Fletcher, A. (2014). Magnetic field tomography,
helical magnetic fields and Faraday depolarization. Mon. Not.
R. Astron. Soc., 441, 2049-2057.
van der Horst, A.J.; Paragi, Z.; de Bruyn, A.G.; … ; Yang,
J.; et al. (2014). A comprehensive radio view of the extremely
bright gamma-ray burst 130427A. Mon. Not. R. Astron. Soc.,
444, 3151-3163.
Mottram, J.C.; Kristensen, L.E.; van Dishoeck, E.F.; … ;
Liseau, R.; et al. (2014). Water in star-forming regions with
Herschel (WISH). Astron. Astrophys., 572.
Mulcahy, D.D.; Horneffer, A.; Beck, R.; … ; Conway, J.; ...
; Horellou, C.; et al. (2014). The nature of the low-frequency
emission of M 51 First observations of a nearby galaxy with
LOFAR. Astron. Astrophys., 568, A74.
Muller, S.; Combes, F.; Guelin, M.; … ; Aalto, S.; ... ; Black,
J.H.; … ; Horellou, C.; ... ; Marti-Vidal, I.; et al. (2014). An
ALMA Early Science survey of molecular absorption lines
toward PKS 1830-211 Analysis of the absorption profiles.
Astron. Astrophys., 566.
Muller, S.; Black, J.H.; Guelin, M.; … ; Aalto, S.; ... ;
Horellou, C.; et al. (2014). Detection of chloronium and
measurement of the Cl-35/Cl-37 isotopic ratio at z=0.89 toward
PKS 1830-211. Astron. Astrophys., 566.
Indebetouw, R.; Matsuura, M.; Dwek, E.; … ; Marti-Vidal,
I.; et al. (2014). Dust Production and Particle Acceleration in
Supernova 1987A Revealed with Alma. Astrophys. J. Letters.,
782, 6.
Muller, T.; Balog, Z.; Nielbock, M.; ... ; Olberg, M.; et al.
(2014). Herschel celestial calibration sources. Exp. Astron. 37,
253-330.
Jelic, V.; de Bruyn, A.; Mevius, M.; … ; Conway, J.; et al.
(2014). Initial LOFAR observations of epoch of reionization
windows II. Diffuse polarized emission in the ELAIS-N1 field.
Astron. Astrophys., 568, A101.
Oonk, J.B.R.; van Weeren, R.J.; Salgado, F.; … ; Batejat,
F.; … ; Conway, J.; et al. (2014). Discovery of carbon radio
recombination lines in absorption towards Cygnus A. Mon.
Not. R. Astron. Soc., 437, 3506-3515.
22
Parise, B.; Bergman, P.; Menten, K. (2014). Characterizing
the chemical pathways for water formation - a deep search for
hydrogen peroxide. Faraday discuss., 168, 349-367.
Perez-Torres, M.A.; Lundqvist, P.; Beswick, R.J.; ... ; MartiVidal, I.; et al. (2014). Constraints on the Progenitor System
and the Environs of SN 2014J from Deep Radio Observations.
Astrophys. J., 792, 38.
A wise bird, a Eurasian
eagle-owl, overlooking the
department’s production of
scientific articles.
Photo: Magnus Thomasson
Persson, C.M.; Gerin, M.; Mookerjea, B.; Black, J.H.; Olberg,
M.; et al. (2014). First detection of [NII] 205 μm absorption in
interstellar gas. Herschel-HIFI observations towards W31C,
W49N, W51, and G34.3+0.1. Astron. Astrophys., 568, 37.
Persson, C.M.; Hajigholi, M.; Hassel, G.; Olofsson, A.O.H.;
Black, J.H.; ... ; Wirström, E.; Olberg, M.; Hjalmarson, Å.;
et al. (2014). Upper limits to interstellar NH+ and para-NH2abundances. Herschel-HIFI observations towards Sgr B2 (M)
and G10.6-0.4 (W31C). Astron. Astrophys., 567, A130.
Ramstedt, S.; Mohamed, S.; Vlemmings, W.; Maercker, M.;
... ; De Beck, E.; Lindqvist, M.; Olofsson, H.; et al. (2014).
The wonderful complexity of the Mira AB system.Astron.
Astrophys., 570, L14.
Ramstedt, S.; Olofsson, H. (2014). The (CO)-C-12/(CO)-C-13
ratio in AGB stars of different chemical type Connection to
the C-12/C-13 ratio and the evolution along the AGB. Astron.
Astrophys., 566.
Raza, H.; Yang, J.; Pantaleev, M. (2014).Integration of ultrawideband planar baluns into the Eleven feed. IET Microw.
Antenna. P., 8, 22-28.
Richards, A.M.S.; Impellizzeri, C.M.V.; Humphreys, E.M.;
… ; Vlemmings, W.; … ; De Beck, E.; ... ; Muller, S.; ... ;
O’Gorman, E.; et al. (2014). ALMA sub-mm maser and dust
distribution of VY Canis Majoris. Astron. Astrophys., 572.
Rodriguez, M.I.; Villar-Martin, M.; Emonts, B.; ... ; Drouart,
G.; et al. (2014). The molecular gas content of ULIRG type 2
quasars at z < 1 (Research Note). Astron. Astrophys., 565.
Romeo, A.; Agertz, O. (2014). Larson’s scaling laws, and the
gravitational instability of clumpy discs at high redshift. Mon.
Not. R. Astron. Soc., 442, 1230-1238.
Romero-Canizales, C.; Herrero-Illana, R.; Perez-Torres,
M.A.; … ; Conway, J.; et al. (2014). The nature of supernovae
2010O and 2010P in Arp 299 - II. Radio emission. Mon. Not. R.
Astron. Soc., 440, 1067-1079.
Tafoya Martinez, D.; Franco-Hernandez, R.; Vlemmings,
W.; et al. (2014). Submillimeter H2O masers in water-fountain
nebulae. Astron. Astrophys., 562, 4.
Ueta, T.; Ladjal, D.; Exter, K.M.; ... ; Vlemmings, W.; et al.
(2014). The Herschel Planetary Nebula Survey (HerPlaNS) I.
Data overview and analysis demonstration with NGC 6781.
Astron. Astrophys., 565.
Varenius, E.; Conway, J.; Marti-Vidal, I.; Aalto, S.; ... ;
Costagliola, F; et al. (2014). The radio core structure of
the luminous infrared galaxy NGC4418 A young clustered
starburst revealed? Astron. Astrophys., 566.
Viti, S.; García-Burillo, S.; Fuente, A.; ... ; Muller, S.; ... ;
Costagliola, F.; ... ; Aalto, S.; et al. (2014). Molecular line
emission in NGC 1068 imaged with ALMA II. The chemistry
of the dense molecular gas. Astron. Astrophys., 570, 28.
Vlemmings, W.; Amiri, N.; van Langevelde, H.; et al. (2014).
From the ashes: JVLA observations of water fountain nebula
candidates show the rebirth of IRAS 18455+0448. Astron.
Astrophys., 569, A92.
van Weeren, R.J.; Williams, W.L.; Tasse, C.; ... ; Horellou,
C.; et al. (2014). LOFAR Low-Band Antenna Observations of
the 3C 295 and Boötes Fields: Source Counts and Ultra-Steep
Spectrum Sources. Astrophys. J., 793, 82.
Wiegert, J.; Liseau, R.; Thébault, P.; … ; Hajigholi, M.; et
al. (2014). How dusty is alpha Centauri? Excess or non-excess
over the infrared photospheres of main-sequence stars. Astron.
Astrophys., 563, A102.
Sakamoto, K.; Aalto, S.; Combes, F.; et al. (2014). An
infrared-luminous merger with two bipolar molecular outflows:
ALMA and SMA observations of NGC3256. Astrophys. J.,
797.
Wirström, E.; Charnley, S.B.; Persson, C.M.; et al. (2014).
Cold Water Vapor in the Barnard 5 Molecular Cloud.
Astrophys. J. Letters., 788.
Santangelo, G.; Antoniucci, S.; Nisini, B.; ... ; Bjerkeli, P.;
... ; Liseau, R.; et al. (2014). First spectrally-resolved H-2
observations towards HH 54 Low H2O abundance in shocks.
Astron. Astrophys., 569, L8.
Zanardo, G.; Staveley-Smith, L.; Indebetouw, R.; ... ; MartiVidal, I.; et al. (2014). Spectral and Morphological Analysis
of the Remnant of Supernova 1987A with ALMA and ATCA.
Astrophys. J., 796, 82.
Santangelo, G.; Nisini, B.; Codella, C.; ... ; Bjerkeli, P.; ... ;
Liseau, R.; et al. (2014). Water distribution in shocked regions
of the NGC 1333-IRAS 4A protostellar outflow. Astron.
Astrophys., 568, A125.
Schilke, P.; Neufeld, D.A.; Müller, H.S.P.; ... ; Black, J.H.;
et al. (2014). Ubiquitous argonium (ArH$^{+}$) in the diffuse
interstellar medium: A molecular tracer of almost purely
atomic gas. Astron. Astrophys., 566, A29, 1-12.
Simpson, J.M.; Swinbank, A.M.; Smail, I.; ... ; Knudsen, K.K.;
et al. (2014). An ALMA Survey of Submillimeter Galaxies
in the Extended Chandra Deep Field South: The Redshift
Distribution and Evolution of Submillimeter Galaxies.
Astrophys. J., 788.
Surcis, G.; Vlemmings, W.; van Langevelde, H.J.; et al. (2014).
Rapidly increasing collimation and magnetic field changes of a
protostellar H2O maser outflow. Astron. Astrophys., 565.
Surcis, G.; Vlemmings, W.; van Langevelde, H.J.; et al. (2014).
The magnetic field at milliarcsecond resolution around IRAS
20126+4104. Astron. Astrophys., 563.
Swinbank, A.M.; Simpson, J.M.; Smail, I.; … ; Knudsen,
K.K.; et al. (2014). An ALMA survey of sub-millimetre
Galaxies in the Extended Chandra Deep Field South: the farinfrared properties of SMGs. Mon. Not. R. Astron. Soc., 438,
1267-1287.
Space Geodesy and Geodynamics
Calves, G.M.; Pogrebenko, S.V.; Cimo, G.; … ; Haas, R.; et
al. (2014). Observations and analysis of phase scintillation
of spacecraft signal on the interplanetary plasma. Astron.
Astrophys., 564.
Graziani, A.; Jarlemark, P.O.J.; Elgered, G.; et al. (2014).
Assessment of Ground-Based Microwave Radiometry for
Calibration of Atmospheric Variability in Spacecraft Tracking.
IEEE Trans. Antennas Propag., 62, 2634-2641.
Hobiger, T.; Otsubo, T. (2014). Combination of GPS and
VLBI on the observation level during CONT11—common
parameters, ties and inter-technique biases. J. Geodesy., 88,
1017-1028.
Hobiger, T.; Haas, R.; Löfgren, J. (2014). GLONASS-R:
GNSS reflectometry with an FDMA based satellite navigation
system. Radio Sci., 49, 271-282.
Löfgren, J.; Haas, R. (2014). Sea level measurements using
multi-frequency GPS and GLONASS observations. EURASIP
J.Adv. Sig. Pr., 2014, no. 12014
Löfgren, J.; Haas, R.; Scherneck, H-G. (2014). Sea level time
series and ocean tide analysis from multipath signals at five
GPS sites in different parts of the world. J. Geodyn., 80, 66-80.
23
Public Outreach
In all 1689 people visited the observatory in
Onsala, its telescopes and exhibition during 2014.
They came on 52 guided tours led by department
students and observatory staff, and as part of two
public open days, during the Gothenburg Science
Festival and on the Mothers’ day open house in
May.
Our SALSA radio telescopes were booked
for an average of 23 hours every week by high
school students and classes from Sweden and
abroad to study interstellar gas in the Milky Way.
Of the 50 users, most were Swedish but some
connected remotely from as far away as Madeira
and Honduras. We have upgraded our SALSAtelescope to be more user friendly, using new
hardware and new software. A new online dataarchive allows users to store their data for later
use, and a new, flexible receiver will enable more
projects using the telescope in the future.
During 2014 we started a program to broaden
our work with schools. Funds awarded from the
Chalmers University of Technology Foundation
were used to buy optical lab equipment to be
used for both visits to schools and for school
students visiting the observatory. All in order of
helping students discover astronomers’ tools and
methods. In November, two 15-year old school
students from the Gothenburg area came to the
observatory as part of their work experience
(prao) week in November. During the year we
also helped three other high school students who
used our SALSA telescopes in projects.
During the Gothenburg Science Festival in
April, we joined forces with city observatory
Slottsskogsobservatoriet for a day of talks and
activities in Slottsskogen in Gothenburg. On
Sweden’s Day and Night of Astronomy on 18
October, we organized our small but unique radio
astronomical star party “Onsala stjärnträff”
for the third time, and a family-oriented Big
Bang Day at science centre Universeum in
collaboration with the Young Academy of
Sweden.
Via press releases, items on Chalmers website,
social media and by direct contact with media,
we communicated news from Onsala facilities
and research by our scientists. In particular, we
communicated news on the upgrade of the 20 m
telescope’s radome, about progress developing
broadband feeds for the Square Kilometre Array,
and the observatory’s innovative GNSS tide
gauge. The radome change and SKA work led
in particular to several appearances on regional
television. Observatory staff handled many
media enquiries on astronomical topics and were
regularly quoted in news media. Sofia Wallström
reported from her observations with the NASArun airborne telescope Sofia in the Chalmers
science blog Forskning pågår. We also translated
and edited the SKA telescope’s new website in
Swedish, http://sweden.skatelescope.org.
Press Clippings
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The sniffer in the harbor going to hunt cheaters
Our research group Optical Remote Sensing was noticed
when they placed a “sniffer” in the Gothenburg harbour
in order to catch ships who ran on illegal fuel. Johan
Mellqvist from the group was interviewd by GP.
GP – December
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Scientists
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T V4, “Nyhet
Facts and Figures
Income (SEK 1,000)2014
20132012
20112010
Research grants
91 513
90,298
86,816
88,868
80,359
Research, faculty funding
41 543
38,099
37,561
35,195
30,032
First degree and Master’s studies
7 720
6,602
5,980
6,394
8,154
Other
2 308
4,003
3,531
4,040
2,816
Chalmers Foundation
1 771
–
125
524
–
Total
First
degree
and
Master's
students
Chalmers
Foundation
Other
Research,
faculty
funding
Research
grants
144 855139,002136,025135,021121,361
Investments Travel
Used grants (SEK 1,000)2014
2013201220112010
Personnel
78 622
74,068
68,504
67,284
61,821
Internal overhead, IT, etc.
17 561
17,410
18,144
17,492
15,640
Fees (APEX, JIVE, etc.)
10 322
9,274
9,580
7,680
10,831
9 505
9,322
8,656
8,776
8,925
12 724
14,279
12,685
19,959
13,462
5 919
6,174
6,472
5,130
4,148
4 110
4,086
3,818
4,500
4,164
Premises
Other
Investments
Travel
Total
Swedish Research Council
46 128
European Community
Swedish National Space Board
Foreign universities
Intl. Org. (ESA, ESO, CNES)
Swedish Energy Agency
VINNOVA (Swedish Govt.
Agency for Innovation Systems)
Total
Personnel (Dec 31)
Professors
Premises
Fees
Personnel
Internal
overhead
138 763 134,613127,859130,821118,991
External funding (SEK 1,000)20142013201220112010
Other
Other
46,006
49,007
50,654
11 821
6,238
12,885
12,378
16,391
16 516
17,429
12,621
10,898
10,862
9 863
10,735
7,413
8,345
5,497
Int.
Organisations
41,801
Others
7,404
2,391
1,548
4,168
-–––
830
2 547
4,553
4,112
4,537
810
95 318 92,36588,42990,34280,359
2014
Swedish
Research
Council
Swedish
National
Space
Board
-––
1,982–
8 443
VINNOVA
European
Community
2013201220112010
1514121112
Adjunct and affiliated professors 77655
Associate professors and
University lecturers
Assistant professors
Researchers
10 8101010
Research engineers
2624212120
Technical staff
1212161312
Ammanuens
Adjunct and
Afilliated
professors
Associate
professors
and
University
lecturers
Assistant
professors
322511
13
10814
Doctoral students
Doctoral
students
Professors
13343
Post doc
Administrative staff
Administrative
staff
77787
25
30
31
36
33
-–2––
Total121
117118114117
Technical
staff
Postdocs
Research
engineers
Researchers
25
Organisation
Our astronomer Eva
Wirström is excited about the
performance of the 20-metre
telescope’s new 3 mm
receiver, which she was one
of the very first to use in May
2014. Eva’s preliminary data
from the dark nebula Barnard
5 seem to show that complex
molecules like formic acid and
acetaldehyde can form even in
the coldest parts of interstellar
clouds.
Departmental Advisory Team
The advisory team’s task is to identify and take a
standpoint on overall strategic issues that are of relevance
to the long-term development of the department, and to
support the department’s steering group in other matters
that may arise. The team met three times during 2014.
External representatives 2014
•Göran Netzler, Chairman
•Göran Berndes, Chalmers’ President’s representative
•Thomas Lewin, Ericsson Research
•Sven Grahn, Swedish Space Corporation
•Marie Rådbo, University of Gothenburg
26
Internal representatives 2014
•Gunnar Elgered, Head of Department
•Camilla Andersson, Secretary
•Alessandro Romeo, Teacher’s representative
•Jo Urban, Teacher’s representative
•Leif Eriksson, Teacher’s representatitve
•Alexey B. Pavolotsky, Technical/Administrative
staff’s representative
•Niklas Falstad, PhD Student’s representative
•Emil Rosenberg, Students’ representative
•Unni Engedahl, Students’ representative
•Kirsten Kraiberg Knudsen, Substitute
The Department went on a great voyage with a “Paddan” boat during the
Day of the Department, on the 28th of August.
Photo: Anders Berg
Management Group
Teaching Staff
The management group handles strategic as well
as operational matters for the department as
a whole. It meets every third week. The group
consists of: the Head of Department, the Deputy
Head, the Vice Head, a Secretary, the Head
of Administration and Finance, the Personnel
Officer, the Director of the Onsala Space
Observatory and our seven research group leaders.
The teaching staff has approximately 30
members. Johan Mellqvist and Arto Heikkilä are
Chairman and Vice Chairman, respectively. The
group has an advisory function on research and
educational issues and meets 4–5 times per year.
Administration and Finance
The group works with organisational and financial planning and follow-up, accounting, study administration,
HR administration, purchasing, web and other forms of communication, as well as any other services needed
by the research and teaching staff. On December 31 the group consisted of:
•Ingrid Jakobson
Head of Administration and Finance
•Paula Rosell
Administrator
• Maria Karlsson
Department Financial Officer
• Paulina Sjögren
Administrator
• Katarina Norheim
Financial Officer
• Oskar Ängermark
Communications Officer
•Camilla Andersson
Administrator
Local Collaboration Group
The Local Collaboration Group is a forum for discussing all issues concerning the management of the
department: appointment of staff members, matters related to the premises and general working conditions,
including the work environment (physical as well as psychosocial) and gender equality.
The group consist of the Head of Department, the Head of Administration and Finance, the Personnel
Officer, three representatives from our unions, a work environment ombudsman and an equality ombudsman,
and meets every sixth week.
27
Department of Earth and Space Sciences
Chalmers University of Technology
SE-412 96 Gothenburg, Sweden
Telephone: +46 31-772 10 00
Internet: www.chalmers.se/rss
28