Status of the XTU-ALPI Complex - INFN-LNL

Transcription

Status of the XTU-ALPI Complex
February 2005
…at the
ALPI-PIAVE Rendez-Vous…
Antonio Dainelli
on behalf of the
XTU-ALPI Operation and Development Groups
INFN
Laboratori Nazionali di Legnaro
LNL-LNS International Scientific Committee Legnaro, the 10th of February 2005
Antonio Dainelli
1
Contents
•
…at the ALPI-PIAVE Rendez-Vous
Low Energy Electrostatic Accelerators
– AN2000
– CN
•
XTU-ALPI Complex
– Completion of the Nb/Cu upgrading programme
– ALPI structure and performances
– Troubles/Works after 10 years of ALPI (1994-2004)
•
Cryogenic System
– New compression system under commissioning
– L&G-He Distribution Line Modification (July 2003ÎJune 2004)
– Cryogenic Plant Fault of October 2004
•
Conclusions
Antonio Dainelli
2
Low Energy Electrostatic Accelerators
AN-2000
• wide range of research activities
• strong scientific demand
• 3.5 unit of personnel fully dedicated
recently renewed
• up-grading phase of the Control
System for both accelerators
CN
Antonio Dainelli
3
7-MV CN Van de Graaff
Antonio Dainelli
4
7-MV CN Van de Graaff
Available beams
Beams
1
H+
2 +
H
2 +
H
2 +
H
Target
(thick)
Energy
[MeV]
Current
[nA]
Li
Be
Be
3
H
7
<5
5 -7
<7
500 (< 3000)
300 (< 3000)
100 (< 3000)
< 3000
Antonio Dainelli
5
2-MV AN2000 Van de Graaff
Available beams
H+, 2D+, 4He2+ (N, Ar)
1
micro-beam facility
10 µm spots on target
Single Particle Events
Antonio Dainelli
6
renewed 60° beam line
Vacuum Control Automatization
Antonio Dainelli
7
Works in Progress (ready from September 2005):
• New Console (Signal digitalization, computer
controlled)
• Automatic conditioning
• New Terminal Design (Safety with Hydrogen gas
and Leaks from the Palladium Valve)
Antonio Dainelli
8
Renewed 60° Beam Line
Vacuum Control Automatization
Antonio Dainelli
9
XTU-PIAVE-ALPI Complex
SC
Booster
ALPI
Positive Ion Injector
Under
Commissioning
PIAVE
EX. Hall 3
Upgraded
ECRIS
ALICE
350kV platform
15 MV
XTU-Tandem
EX. Halls 1 and 210
Antonio Dainelli
Medium β 160 MHz
Nb/Cu or Pb/Cu
High β 160 MHz
Nb/Cu.
CR12 CR13 CR14 CR15CR16 CR17 CR18 CR19 CR20
B3
B4
COLD BOX
CR10 CR9 CR8 CR7 CR6 CR5 CR4 CR3
B2
Low β 80 MHz
Full Nb
ALPI
layout
XTU
TANDEM
Antonio Dainelli
P
I
A
V
E
11
EXPERIMENTAL
HALLS 1, 2
7000
6000
5000
4000
3600
hours
3000
2000
1000
04
20
02
20
00
20
98
Operational Experience
19
96
19
94
19
19
19
92
0
90
Beam on Target (hours)
XTU-ALPI
Upgrading
Beam on
Target of ALPI
Time (years)
Antonio Dainelli
12
Overall parameters
•
Of the XTU-ALPI Complex
Ion Species
(see the published list on the LNL website developed by the Sources and Injectors Service)
– All stable nuclei (except noble gases) up to A = 109 u (109Ag )
–
•
90,91,92,94,96Zr
74,76,77,78,80,82Se
127I
197Au
+ Enriched Isotopes
–
•
40,48Ca
26Mg, 33S, 36S, 48Ca, 50Cr, 54Fe, 64Ni, 74Se
Beam Currents
– few hundreds of p-nA at the XTU injection
– from few tenths of p-nA up to few hundreds of p-nA from XTU
– few p-nA from ALPI (1-10 p-nA) according to ion masses
Antonio Dainelli
13
Overall parameters
•
Of the XTU-ALPI Complex
Ion Energies
(delivered ion beams during the last three years without LOW-β section)
– up to 20 MeV/u with
12C
– between 15 MeV/u and 5 MeV/u with light and medium ion masses
– Up to 6 MeV/u with
104Ru
•
Time Resolution on the exp. Target: 700 ps (FWHM) (bunch length)
•
But, still difficulties in delivering High Energy Low Rate beams (600
MeV of
40Ca,
400 ns period) with less than 200 p-nA from the
sputtering source (external XTU stripping solution under test) .
Antonio Dainelli
14
ALPI medium β
Pb/Cu resonators
•
50 installed resonators
from 1992 to 1994
•
•
Pb/Cu, 160 MHz
Average Ea @7W =2,68
MV/m (fresh cavities)
•
Four cavities still
installed in the bunching
cryostats
Antonio Dainelli
15
Pb
Nb
On Line Results
A. Porcellato and coll.
Ea (@7 W): from 2.4 (Pb) to 4.4 MV/m (Nb)
Despite some limitations in the copper base
(not best Cu quality, sharp edges & Sharp holes
in high-I regions, hidden volumes in brazed joints)
• No interference with ALPI operation
• Same cryostat, control system, rf hardware
and software
790 keV/u
(@ β=βop;Φ=0)
Antonio Dainelli
4.4 MV/m
16
Nb/Cu resonator
Advantages
QWR
A. Porcellato and coll.
• High accelerating fields
• High mechanical stability
Tuning Plate
• Frequency not affected by changes in the He bath pressure
(<O.01 Hz/mbar!)
• Locked up to 7 MV/m without necessity of fast or “soft” tuners
• Very reliable
• Easy to put into operation
• No degradation with time after installation
Antonio Dainelli
17
ALPI High β section
sputtered Nb/Cu
QWRs
Q
1.00E+10
1W
3W
1.00E+09
7W
CR20-1
CR20-2
1.00E+08
CR20-3
CR20-4
1.00E+07
beam port
0
1
2
3
4
5
6
7
8
9
10
11
coupler
pick-up
Ea [MV/m]
ALPI β=0.13 160MHz
resonator views; The cavity has
no brazed joint; beam ports are
jointed to resonator by indium
gaskets
Antonio Dainelli
18
12
9
8
7
6
5
4
3
2
1
0
Resonator number
Antonio Dainelli
CRB4-2
CR20-2
CR19-2
CR18-2
CR17-2
CR16-2
CR15-2
CR14-2
CR13-2
CR12-2
CR10-4
CR09-4
CR08-4
CR06-4
Electroplated Pb/Cu (medium beta)
Sputtered Nb/Cu (upgraded medium beta)
Sputtered Nb/Cu (high beta)
Bulk Nb (low beta)
CRB2-1
E a (MV/m)
ALPI 1998
Resonator Accelerating Fields at 7 W
19
ALPI 2002
10
Bulk Nb (low beta)
E a (MV /m)
8
6
4
2
CR -1
13
CR -1
14
CR -1
15
CR -1
16
CR -1
17
CR -1
18
CR -1
19
CR -1
20
-1
12
CR
CR
04
CR -1
05
CR -1
06
CR -1
07
CR -1
08
CR -1
09
CR -1
10
-1
0
Resonator number
Antonio Dainelli
20
ALPI 2002 (December)
9
8
7
Bulk Nb (low beta)
Ea (MV/m)
6
5
4
3
2
1
B3
-1
CR
12
-1
CR
12
-4
CR
13
-3
CR
14
-2
CR
15
-1
CR
15
-4
CR
16
-3
CR
17
-2
CR
18
-1
CR
18
-4
CR
19
-3
CR
20
-2
CR
10
-3
CR
09
-4
CR
09
-1
CR
08
-2
CR
07
-3
CR
06
-4
CR
06
-1
CR
05
-2
CR
CR
04
-3
0
Resonator number
Antonio Dainelli
21
ALPI October 2003
9
Electroplated Pb/Cu (m edium beta)
8
Sputtered Nb/Cu (upgraded m edium beta)
Ea (MV/m)
7
Bulk Nb (low beta)
6
4.4
5
4
3
2.4
2
CR
13
-1
CR
14
-2
CR
15
-3
CR
16
-4
CR
18
-1
CR
19
-2
CR
20
-3
0
CR
04
-2
CR
05
-3
CR
06
-4
CR
08
-1
CR
09
-2
CR
10
-3
1
Resonator number
Antonio Dainelli
22
XTU + ALPI 2004
ALPI Specific Energy [MeV/u]
30
energy upgrade completed
25
Foil
Gas-Foil
20
Foil-Foil
15
10
5
20 40 60 80 100 120 140 160 180 200
A
Ion specific energies in the present ALPI configuration with
the completed program of energy upgrade (replacement of
Pb by sputtered Nb)
Antonio Dainelli
23
accelerated beams in ALPI 2000-2001
Date
ion
Cavities
βin
βout
Energy Gain
/ chargexcavity
[MeV/ch-un cav.]
Final
Energy
[MeV]
Final
Energy
[MeV/u]
21FEB00
32S12+
25
0.107
0.142
0.435
300
9.4
27FAR00
36S12+
29
0.101
0.140
0.449
328
9.1
02MAR00
62Ni11+
14
0.088
0.105
0.428
316
5.1
14MAR00
48Ca9+
18
0.079
0.097
0.436
206
4.3
14NOV00
32S9,12+
31
0.107
0.153
0.477
350
10.9
22NOV00
58Ni6,15+
29
0.084
0.114
0.340
330
5.7
04FEB01
58Ni13+
13
0.087
0.100
0.395
267
4.6
14FEB01
58Ni13+
29
0.087
0.118
0.456
380
6.5
22FEB01
82Se11,17+
41
0.079
0.123
0.502
590
7.2
03MAR01
82Se11,17+
43
0.079
0.128
0.537
631
7.7
15JUN01
36S9+
22
0.093
0.117
0.429
230
6.4
29JUN01
74Se18+
22
0.085
0.111
0.439
422
5.7
07JUN01
83Se6,16+
32
0.074
0.110
0.487
464
5.6
12JUL01
65Cu6,15+
12
0.079
0.093
0.374
260
4
05NOV01
12C6+
43
0.137
0.208
0.526
240
20
13NOV01
56Fe6+
32
0.083
0.120
0.563
380
6.8
Antonio Dainelli
24
accelerated beams in ALPI 2002
Date
ion
Cavities
βin
βout
Energy Gain
/ chargexcavity
[MeV/ch-un cav.]
Final
Energy
[MeV]
Final
Energy
[MeV/u]
20FEB02
12C6+
43
0.134
0.207
0.541
240
20.
26FEB02
16O7+
44
0.124
0.197
0.567
289
18.
02MAR02
48Ca9+
29
0.080
0.112
0.525
280
5.8
14MAR02
48Ca9+
18
0.079
0.097
0.616
206
7.8
24MAY02
64Ni11,16+
29
0.088
0.113
0.585
500
7.8
01JUN02
16O7,8+
30
0.130
0.183
0.520
250
15.6
30JUN02
32S9,12+
46
0.099
0.176
0.572
463
14.5
31OCT02
32S9,12+
41
0.108
0.176
0.587
463
14.5
08NOV02
80Se11,18+
33
0.081
0.127
0.598
600
7.5
16NOV02
12C6+
43
0.134
0.207
0.539
240
20.
27NOV02
40Ca10+
15
0.092
0.116
0.605
250
6.25
01DEC02
16O7+
15
0.092
0.116
0.605
250
6.25
05DEC02
83Se6,16+
35
0.124
0.183
0.553
250
15.6
10DEC02
104Ru12,20
29
0.075
0.111
0.566
600
5.8
14DEC02
32S9+
15
0.098
0.124
0.643
230
7.2
20DEC02
12C6 +
43
0.134
0.207
0.542
240
20.
Antonio Dainelli
25
accelerated beams in ALPI 2003-2004
Date
ion
Cavities
βin
βout
Energy Gain
/ chargexcavity
[MeV/ch-un cav.]
Final
Energy
[MeV]
Final
Energy
[MeV/u]
08JUN03
64Ni12+
14
0.080
0.100
0.660
300
4.7
04JUL03
48Ca9+
14
0.080
0.106
0.600
220
4.6
03NOV03
16O6+
17
0.080
0.149
0.631
166
10.3
10NOV03
80Se11,18+
35
0.077
0.149
0.634
630
7.9
19FEB04
54Cr10+
22
0.080
0.108
0.615
295
5.5
05MAR04
40Ca10,14+
47
0.104
0.184
0.651
631
13MAR04
54Cr11+
20
0.080
0.108
0.616
295
5.5
16MAR04
58Ni11+
31
0.077
0.114
0.563
350
6.0
25MAR04
36Cr9+
12
0.094
0.116
0.704
225
6.2
01APR04
64Ni11+
35
0.075
0.116
0.602
400
6.2
13APR04
82Se12+
46
0.068
0.115
0.597
505
10 p-nA
23APR04
90Zr13+
46
0.067
0.115
0.612
555
10 p-nA
not delivered on target
ALPI had been out of operation in May-July 2004 for the Up-Grading of the Cryogenic Lines.
The runs scheduled by November 2004 were stopped because of a Cryogenic Plant Failure
Antonio Dainelli
26
2004
main achievements after 10 years of operation
•
average accelerating field increased from 2.4 MV/m
(Pb/Cu) to 4.4 MV/m (Nb/Cu) in the mediumbeta section and 6 MV/m in the high-beta section)
(A. Porcellato and coll.)
•
Increased reliability of the cryogenic system
(PC3000 EUROTHERM)
•
Specific Kinetic Energies in the range of
•
Intensities of about 10 p-nA with ion masses in the
range of A=100 (Zr, Ru) (only 1 stripper foil on XTU)
– 20 MeV/u for 12C
– 6 MeV/u with A=100
Antonio Dainelli
27
1994-2004
main problems after 10 years of operation
•
poor overall cryogenic power
– 2 new cycle compressors are under commissioning
•
poor L/G-He distribution towards the
low-energy branch
– modification made in June 2004;
– distribution lines had been vacuum tested
– Cryogenic tests to be done soon (post-poned from
September 2004 because of the Cryogenic Plant
Failure); see time schedule
Antonio Dainelli
28
1994-2004
minor (?) problems after 10 years of operation
• Leaks in the cooling circuit of the
magnets (quad Triplets and Dipoles)
• Leaks in the cooling circuit of the
magnet power supplies
– All transistor boards replaced in June 2004
• power supplies failures because of the
age of the electronic components
(phase
detectors, electrolitic capacitances, electronic boards)
Antonio Dainelli
29
ALPI is 10 years old on paper ...
But
•
Cryostat components (cryogenic valves) renewed during the last 5
years;
•
QWRs of the Medium-β section completely re-sputtered in Nb; Lowβ tuning devices re-designed in 2004; High-β section QWRs in good
condition;
•
Cryogenic Plant modified and up-graded in 2004 (to be tested);
•
Control System up-graded with new Operating Systems
•
Magnet Power Supplies renewed in 2004
•
Magnets (Doublets and Triplets) remain the old part; water leaks
Antonio Dainelli
30
Bulk Nb resonators ( Low Beta )
•
High accelerating field at reduced power consumption
(more than 7 MV/m at 7 W in average)
•
No degradation due to Q desease
•
Sensitivity to vibrations reduced by a mechanical damper
•
Changes in frequency due the He bath drift in pressure
compensated by “soft tuners”
•
Locked on line up to 6 MV/m
•
fNot used for beam acceleration up to October 2002
because of difficulties in the cooling down of the cryostats
Antonio Dainelli
31
Low-β tuner system upgrade
•
Extended on-line tests of the low beta QWRs
(A.Facco and coll., November 2003) confirmed
the poor locking capability of the old tuning
system in the ALPI environment; (back lash of
mechanical cold actuators, plastic deformations of the bottom
plate, difficulties to follow the pressure fluctuations of the Hebath)
•
A new tuning device had tested in 2004 (A.
Facco and coll.);
– new tuners installed on all the 12 QWRs of the Low-β
section (tested on PIAVE QWRs;
– On-line tests of the new tuning devices will be done
as soon as the Cryogenic Plant Failure will be
recovered (beam transport included); see schedule
Antonio Dainelli
32
Low-β tuning device upgrading
•
A. Facco, S. Canella, D. Carlucci, F. Scarpa
Activities 2004...Facco et coll.
Antonio Dainelli
33
Low-β tuning device upgrading
• C-flex joints do not deteriorate the Q (> 109) of the QWR
• good linearity, resolution and reliability
• tuning range > 10 kHz
30
25
20
15
Spinta1
Ritorno1
Spinta2
10
5
-150
-100
-50
0
-5 0
-10
-15
50
Steps
100
150
Hz
-20
Figure 5: Frequency change vs. tuner step, tested at
4.2K with an 80 MHz superconducting resonator.
Antonio Dainelli
34
He Cycle Compressors (September 2003)
• With the installation of the new compressor three different
combinations of G-He flux will be possible and the
maximum flux will be limited to 190 g/s by the Cold-Box
A
65 g/s
A+B
160 g/s
B
95 g/s
A+C
175 g/s
B+C
205 g/s
C
110 g/s
Antonio Dainelli
Limited to 190 g/s by
the Cold-Box
35
Modification of the
L/G-He Distribution Lines
(July 2003)
• In July 2003 the L&G-He Distribution Lines will be
modified in order to bring more cryogenic power to the
low-energy branch of ALPI;
Postponed to June 2004
• Essentially, there will be two different injection points and
two extraction points;
• Both the main Cold-Box and the auxiliary Cold-Box (LN2/G-He heat exchanger) will inject G-He towards the
cryostat shields from the same points.
Antonio Dainelli
36
Final Goals of the Cryogenic
Distribution Line Modification (June)
•
optimize the cryogenic power distribution towards
the low energy branch of ALPI ;
•
cool down properly the low-β cryostats (shields and
cavities);
•
reduce,
if
it
will
be
possible,
the
pressure
fluctuations of the L-He bath (amplitude and time
speed );
•
define new cryogenic operation procedure in order to
reach a better overall stability (5000 litres Dewar +
spill + increase of the gas flux from the cycle
compressors up to 190 g/s)
Antonio Dainelli
37
Main components of the cryogenic up-grading
• 4 new cryogenics Valve Boxes (8 proportional valves and 6
on/off valves):
-
VB1
injection 80 K and 4.5 K + liquid spill to the external dewar
VB2
junction of the Liq./Refr. and Heat Exchanger lines
VB3
equalization valves and return lines towards Liq./Refr.
VB4
ring closure
• New Flux Gauges (Venturi tube) on the Liq./Refr. output;
• New return lines (DN 40 and DN 32) from the VB3 valve box
toward VB2 (Liq./Refr.);
• New lines from the Heat Exchanger to the VB2 valve box;
• New line for the L-He spilling from the Cold Box Dewar.
Antonio Dainelli
38
Cryogenic Line Modification
VB1
G-He/LN2 heat exchanger
VB2
gas 80 K
liquid 7 K
VB3
Antonio Dainelli
VB4
39
He transfer to the lower b branch
1. More total ∆P for
cooling (30→70 mbar),
refrigerator and cryostats
valves changed
(done in 07/03)
Liquid
Gas
Main
Cold
Box
2. More He Flux
2→4 compressors
(160 to 205 g/s)
(received 09/03)
3. Equalization of hydraulic
routes to various
cryostats
(to be tested)
∆P ~ K on each cryostat
7K
3. Equalization of hydraulic routes to cryostats
Antonio Dainelli
4.5 K
(similarly for thermal shield gaseous He)
40
General View
VB4
VB1
VB3
VB2
Liq./Refr.
Antonio Dainelli
41
General View (top)
VB1
VB2
Liquefattore/Refr.
VB3
Return Lines
with
Pressure Stabilization Valves
Antonio Dainelli
VB4
Ring closure
42
VB2 Positioning
June 2004
Antonio Dainelli
43
VB2 Positioning
June 2004
Antonio Dainelli
44
VB4 Positioning
June 2004
Antonio Dainelli
45
VB3 Positioning
June 2004
Antonio Dainelli
46
Flux Measurement devices (Venturi tubes)
June 2004
Antonio Dainelli
47
VB2 Valve Box with Flux Measurement
devices (Venturi tubes)
June 2004
Antonio Dainelli
48
Cryogenic Plant Failure ...
•
At the plant restart in October 2004, after the
modification of the Distribution Lines, the Warm Turbine
stopped after few days of work;
•
Dismounting the two turbine showed
– Strong Oil Contamination on the warm part of
Cold and Warm Turbines
– No evident origin of the contamination also after
a carefull examination of all the plant components
together with AIR LIQUIDE experts in December
2004
Antonio Dainelli
49
Warm Turbine October 2004
Oil droplets on the flange
Antonio Dainelli
50
... Cryogenic Plant Failure ...
•
The two turbines were sent to Sassenage for their
maintenance (Warm turbine was found broken while the
Cold one was not damaged);
•
The Cryogenic plant started again in January and the
improved gas dyagnostics put in evidence a strong pollution
of Water (50 vpm) and Nitrogen (160 vpm);
•
After few days of working, looking for the source of pollution,
the Warm Turbine stopped again and after its dismounting
the same strong oil contamination was found (oil droplets on
the external part of the vacuum flange);
Antonio Dainelli
51
Warm Turbine January 2005
Oil droplets on the flange
Antonio Dainelli
52
... Cryogenic Plant Failure ...
•
The two turbines has been sent again this week to
Sassenage for their maintenance;
•
The search for the water pollution revealed these week a
leak on the Water/Oil Heat Exchanger of the Compressor A
•
Next week, both the AIR LIQUIDE Plant Designer (Gistau)
and the Reponsible for the Plant Commissioning and UpGrading (Bonneton) will be at LNL together with two further
AIR LIQUIDE engineers to look for the origin of the Fault;
Antonio Dainelli
53
Conclusions
•
The Energy Upgrade of ALPI is completed and accelerating
fields in excess of 4 MV/m are available all along the
accelerator;
•
After the Distribution Line Modification of June 2004 (and
the recovery from the Cryogenic Plant Failure) the
cryogenic plant should be able to cool down properly all the
ALPI sections (in particular the low-beta section) ready to
match the PIAVE requirements for the injection of low-beta
ions.
•
The new tuning devices, together with a reduced pressure
fluctuations (amplitude and time speed) of the L-He bath
(to be proved), should be able to keep locked the low-beta
QWRs (bulk Nb) .
54
Antonio Dainelli

Status of the XTU-ALPI Complex - INFN-LNL

Transcription

Similar documents

4.28 BEST OF THE BEST pgs. 1-12

Membership Application - Greater San Antonio Builders Association

328 Acres in San Antonio, Texas

¡VIVA SA RUN!

ANTONIO$FRANCESCO$IS$LIVING$PROOF$

FOR SALE - San Antonio Commercial Real Estate

August 2015 Newsletter - Opticians Alliance of New York

by: tim adams bearcat insider

Read more About SARA

Pageflex Persona [document: PRS0004274_00098]