docEXTASIS: EXTinction of Air Shower Induced Signal Coherent radio
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EXTASIS: EXTinction of Air Shower Induced Signal Coherent radio
EXTASIS: EXTinction of Air Shower Induced Signal Coherent radio emission from the air shower sudden death SUBATECH École des Mines de Nantes Université de Nantes CNRS/IN2P3 Benoît Revenu Colloque PNHE, 03/04/2014 Rayons cosmiques d’ultra-haute énergie - Reconstruire les caractéristiques du rayon cosmique : - direction d’arrivée - énergie - nature (principal moteur des upgrades d’Auger) - détection de la gerbe atmosphérique via 3 observables : - particules secondaires atteignant le sol - désexcitation du N atmosphérique suite au passage de la gerbe (fluorescence) - champ électrique radio émis par la gerbe - publi LOFAR en gestation, composition entre 10 eV et 10 eV - sensibilité à la composition similaire à la technique de fluorescence - le signal radio est un indicateur de la nature du primaire, c’est un fait 2 17 Benoît Revenu 18 Colloque PNHE, 03/04/2014 The radio signal understood in great details since ~ 1 year interference of 2 different polarization patterns produced by 2 different mechanisms simu: CoReas simu: LOFAR data LOFAR data Benoît Revenu 3 Colloque PNHE, 03/04/2014 The radio signal Sensitivity to the nature of the primary cosmic ray: Xmax is measured with an uncertainty of ~ 20 (Buitink et al, ICRC 2013) Benoît Revenu 4 2 g/cm Colloque PNHE, 03/04/2014 Radio emission of EAS 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF Benoît Revenu LF MF HF VHF 5 𝞶 UHF Colloque PNHE, 03/04/2014 Radio emission of EAS FINISHED Pioneers of the 70s EASRADIO, Gauhati Akeno, AGASA few events 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF Benoît Revenu LF MF HF VHF 5 𝞶 UHF Colloque PNHE, 03/04/2014 Radio emission of EAS RUNNING FINISHED Pioneers of the 70s EASRADIO, Gauhati Akeno, AGASA AERA, CODALEMA, LOPES, LOFAR... ~6000 events few events ANITA ~20 events 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF Benoît Revenu LF MF HF VHF 5 𝞶 UHF Colloque PNHE, 03/04/2014 Radio emission of EAS RUNNING FINISHED Pioneers of the 70s EASRADIO, Gauhati Akeno, AGASA AERA, CODALEMA, LOPES, LOFAR... ~6000 events few events ANITA ~20 events 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF LF MF HF VHF 𝞶 UHF Lilian Martin ce matin Richard Dallier juste après Benoît Revenu 5 Colloque PNHE, 03/04/2014 Radio emission of EAS RUNNING RUNNING FINISHED Pioneers of the 70s EASRADIO, Gauhati Akeno, AGASA AERA, CODALEMA, LOPES, LOFAR... ~6000 events few events ANITA CROME, MIDAS, AMBER, EASIER ~20 events ~20 events 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF LF MF HF VHF 𝞶 UHF Lilian Martin ce matin Richard Dallier juste après Benoît Revenu 5 Colloque PNHE, 03/04/2014 Radio emission of EAS RUNNING RUNNING FINISHED Pioneers of the 70s EASRADIO, Gauhati Akeno, AGASA AERA, CODALEMA, LOPES, LOFAR... few events ~6000 events Transition radiation, other mechanism? Geomagnetic charge excess ANITA ~20 events 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF LF MF HF VHF CROME, MIDAS, AMBER, EASIER ~20 events Geomagnetic, charge excess, Cherenkov, MBR 𝞶 UHF Lilian Martin ce matin Richard Dallier juste après Benoît Revenu 5 Colloque PNHE, 03/04/2014 Radio emission of EAS RUNNING Pioneers of the 70s EASRADIO, Gauhati Akeno, AGASA AERA, CODALEMA, LOPES, LOFAR... few events ~6000 events Transition radiation, other mechanism? Geomagnetic charge excess ANITA ~20 events NO data, model, simu RUNNING FINISHED 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF LF MF HF VHF CROME, MIDAS, AMBER, EASIER ~20 events Geomagnetic, charge excess, Cherenkov, MBR 𝞶 UHF Lilian Martin ce matin Richard Dallier juste après Benoît Revenu 5 Colloque PNHE, 03/04/2014 Radio emission of EAS NO data NO model NO simu Transition radiation, other mechanism? AERA, CODALEMA, LOPES, LOFAR... ~6000 events Geomagnetic charge excess ANITA ~20 events NO data, model, simu Pioneers of the 70s EASRADIO, Gauhati Akeno, AGASA few events RUNNING RUNNING FINISHED 3-30 kHz 30-300 kHz 0.3-3 MHz 3-30 MHz 30-300 MHz 0.3-3 GHz VLF LF MF HF VHF CROME, MIDAS, AMBER, EASIER ~20 events Geomagnetic, charge excess, Cherenkov, MBR 𝞶 UHF Lilian Martin ce matin Richard Dallier juste après Benoît Revenu 5 Colloque PNHE, 03/04/2014 Radiodetection of EAS in the kHz-MHz range year reference frequency message 1970 Allan, Clay, Nature 225, 253 2 MHz 100 times higher than at 32 MHz 1970 Prescott et al, 11th ICRC 3, 717 3.6 MHz, 10 MHz higher than geomagnetic, no detection at 10 MHz 1971 Stubbs, Nature 230, 172 2 MHz 250 times higher than at 44 MHz 1971 Hough et al, Nature 232, 14 3.6 MHz 10 times higher than geomagnetic in 20-60 MHz 1972 Felgate, Stubbs, Nature 239, 151 6 MHz two polarizations, not only geomagnetic 1.5 1973 Clay et al, 13th ICRC 4, 2420 100 kHz 1973 Gregory et al, Nature 245, 86 100 kHz 1985 Suga et al, 20th ICRC 7, 268 1987 Nishi, Suga, 20th ICRC 6, 125 26-300 kHz Akeno, monopolar, 1/d, 2.5 km 1991 Castagnoli et al, 22nd ICRC 4, 363 470 kHz, 2.6 MHz EASTOP/EASRadio, amplitude ↗ when freq ↘ 1992 Baishya et al, NCimC 16, 17 2 MHz, 9 MHz TR is not the only mechanism 1993 Kadota et al, 18th ICRC 4, 262 30 kHz-3 MHz AGASA, mono/bi polar Benoît Revenu "⌫ / ⌫ large SNR, not only geomagnetic 50 kHz, 170 kHz, 1.6 MHz Akeno, huge field strength vs geo-magnetic/electric 6 Colloque PNHE, 03/04/2014 Radiodetection of EAS in the kHz-MHz range year reference frequency message 1970 Allan, Clay, Nature 225, 253 2 MHz 100 times higher than at 32 MHz 1970 Prescott et al, 11th ICRC 3, 717 3.6 MHz, 10 MHz higher than geomagnetic, no detection at 10 MHz 1971 Stubbs, Nature 230, 172 2 MHz 250 times higher than at 44 MHz 1971 Hough et al, Nature 232, 14 3.6 MHz 10 times higher than geomagnetic in 20-60 MHz 1972 Felgate, Stubbs, Nature 239, 151 6 MHz two polarizations, not only geomagnetic 1.5 1973 Clay et al, 13th ICRC 4, 2420 100 kHz 1973 Gregory et al, Nature 245, 86 100 kHz 1985 Suga et al, 20th ICRC 7, 268 1987 Nishi, Suga, 20th ICRC 6, 125 26-300 kHz Akeno, monopolar, 1/d, 2.5 km 1991 Castagnoli et al, 22nd ICRC 4, 363 470 kHz, 2.6 MHz EASTOP/EASRadio, amplitude ↗ when freq ↘ 1992 Baishya et al, NCimC 16, 17 2 MHz, 9 MHz TR is not the only mechanism 1993 Kadota et al, 18th ICRC 4, 262 30 kHz-3 MHz AGASA, mono/bi polar Benoît Revenu "⌫ / ⌫ large SNR, not only geomagnetic 50 kHz, 170 kHz, 1.6 MHz Akeno, huge field strength vs geo-magnetic/electric 6 Colloque PNHE, 03/04/2014 Emission mechanisms in the kHz-MHz range • • • • • Benoît Revenu year reference mechanism 1957 Wilson, Phys. Rev. 108, 155 geoelectric 1968 Charman, J. Atm. Terr. Phys. 30, 195 geoelectric 1972 Allan, Nature 237, 384 maximum coherence 1983 Kaneko et al, 18th ICRC 11, 428 charge-excess in air and at the ground 1985 Nishimura, 20th ICRC 7, 308 TR of electrons on the ground 1985 Suga et al, 20th ICRC 7, 268 TR of electrons on the ground Summary extensive air showers emit a strong electric field at low frequencies (< MHz) clear evidence of a strong increase of the radio pulses amplitude with decreasing frequencies no definitive conclusion, not enough data, no proper atmospheric monitoring no satisfactory underlying mechanism low frequency band unsued since 20 years 7 Colloque PNHE, 03/04/2014 Air shower sudden death Proposed mechanism (TR not considered): the sudden death of the shower front when reaching the ground level generates a coherent electric field at low frequency macroscopic very strong time variation of J and ρ! ~ instantaneous at low frequencies (< 20 MHz, >15 m): coherence microscopic the coherent deceleration, ie Bremsstrahlung, of the electrons is responsible for the strong electric field J(x, y, z, t) ⇢(x, y, z, t) Benoît Revenu ground Characterize the sudden death signal with the simulation (code SELFAS) 8 Colloque PNHE, 03/04/2014 Sudden death pulse Benoît Revenu ground Colloque PNHE, 03/04/2014 Sudden death pulse Benoît Revenu ground Colloque PNHE, 03/04/2014 Sudden death pulse Benoît Revenu ground Colloque PNHE, 03/04/2014 Sudden death pulse Benoît Revenu ground 10 Colloque PNHE, 03/04/2014 Sudden death model: amplitude, time structure C • • simple model based on the ground particles distribution validated for vertical and inclined showers s(t = r/c) / Z 2⇡ 0 L(⇢) d correlated to the total number of e-/e+ Benoît Revenu A 11 Colloque PNHE, 03/04/2014 Arrival time in antenna (ns) Sudden death model: amplitude, time structure C • • simple model based on the ground particles distribution validated for vertical and inclined showers s(t = r/c) / Z 2⇡ 0 L(⇢) d correlated to the total number of e-/e+ Benoît Revenu A 11 Colloque PNHE, 03/04/2014 Arrival time in antenna (ns) Sudden death model: amplitude, time structure C • • simple model based on the ground particles distribution validated for vertical and inclined showers s(t = r/c) / Z 2⇡ 0 L(⇢) d correlated to the total number of e-/e+ Benoît Revenu A 11 Colloque PNHE, 03/04/2014 Arrival time in antenna (ns) Sudden death model: amplitude, time structure C • • simple model based on the ground particles distribution validated for vertical and inclined showers s(t = r/c) / Z 2⇡ 0 L(⇢) d correlated to the total number of e-/e+ Benoît Revenu A 11 Colloque PNHE, 03/04/2014 Arrival time in antenna (ns) Sudden death model: amplitude, time structure C • • simple model based on the ground particles distribution validated for vertical and inclined showers s(t = r/c) / Z 2⇡ 0 L(⇢) d correlated to the total number of e-/e+ Benoît Revenu A 11 Colloque PNHE, 03/04/2014 Arrival time in antenna (ns) Sudden death model: amplitude, time structure C • • simple model based on the ground particles distribution validated for vertical and inclined showers s(t = r/c) / Z 2⇡ 0 L(⇢) d correlated to the total number of e-/e+ Benoît Revenu A 11 Colloque PNHE, 03/04/2014 Arrival time in antenna (ns) Sudden death model: amplitude, time structure C • • simple model based on the ground particles distribution validated for vertical and inclined showers s(t = r/c) / Z 2⇡ 0 L(⇢) d correlated to the total number of e-/e+ Benoît Revenu A 11 Colloque PNHE, 03/04/2014 Sudden death pulse: some characteristics Amplitude: scales as E Polarization: lies in the plane transverse to the direction observer-shower core, vertical component Benoît Revenu 12 Colloque PNHE, 03/04/2014 Sudden death pulse: some characteristics Amplitude: scales as E Polarization: lies in the plane transverse to the direction observer-shower core, vertical component Vertical shower, 10 EeV Principal pulse amplitude decreases exponentially, SDP amplitude decreases as 1/dcore Benoît Revenu 12 Colloque PNHE, 03/04/2014 Sudden death pulse: some characteristics Amplitude: scales as E Polarization: lies in the plane transverse to the direction observer-shower core, vertical component Vertical shower, 10 EeV 1 mV/m /m Expected amplitude as a function of the primary characteristics detectable for a wide range of shower parameters Principal pulse amplitude decreases exponentially, SDP amplitude decreases as 1/dcore Benoît Revenu 100 µV 10 µV /m /m V 1µ 12 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i Benoît Revenu ground 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP max tSDP Benoît Revenu ground 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP max tSDP Benoît Revenu ground 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP ti max tSDP ti Benoît Revenu ground 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP ti `i Benoît Revenu ground max tSDP ti 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP ti `i Benoît Revenu ground max tSDP ti 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP ti `i Benoît Revenu ground max tSDP ti 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP ti `i Benoît Revenu ground max tprod max tSDP ti 13 Colloque PNHE, 03/04/2014 Sudden death signal: absolute timing bijective relation between the time in the antenna and the shower development ti ⟼ ` i ⟼ X i max tSDP ti `i max tprod max tSDP ti atmospheric depth X (g.cm-2) Benoît Revenu ground 13 Colloque PNHE, 03/04/2014 Sudden death: absolute timing The production of maximum electric field occurs well before Xmax, close to Xinf Benoît Revenu 14 Colloque PNHE, 03/04/2014 Sudden death: absolute timing The production of maximum electric field occurs well before Xmax, close to Xinf Benoît Revenu 14 Colloque PNHE, 03/04/2014 Summary from the simulations, the SDP contains many informations on the shower, in particular an indication that the maximum of emission of the electric field occurs well before Xmax ! The signal gives a measurement of the total number of e+/e- that reached the ground: very important for composition studies ! The amplitude scales as 1/dcore, providing a signal detectable up to large distances from the shower core (as already seen in Akeno in 1987) ! need a dedicated antenna, sensitive to: • low frequencies (below 20 MHz) • vertical polarization • horizontal incoming directions Benoît Revenu 15 Colloque PNHE, 03/04/2014 EXTASIS EXTinction of Air Shower Induced Signal Financé par la Région Pays de la Loire, depuis fin 2013, pour 4 ans soutien du PNHE site choisi : Nançay, au cœur de CODALEMA3 équipe : SUBATECH, LESIA, US Nançay (13 personnes) 1 postdoc, 1 thèse Avril-mai 2014 Antenne Butterfly (CODALEMA3, AERA…) avec LNA modifié pour les BFs trigger externe (particule ou station autonome) H. Ca rd un er • • • • • Benoît Revenu 16 Colloque PNHE, 03/04/2014 Benoît Revenu 17 Colloque PNHE, 03/04/2014 Air shower sudden death altitude = 1400 m asl acceleration = radiation s e l c i t r a p nd 10 9 gr ou nd pa rt ic le s u o r g 10 6 Benoît Revenu ground 18 Colloque PNHE, 03/04/2014 Sudden death: summary pulse main (nXB) sudden death geometry depends on the axis distance depends on the core distance polarization polarization along n X B at 1st order polarization in the plane ⊥ AC frequency between 1 MHz and ~ GHz below 20 MHz spectrum timing E-production shape depends on d same shape, coherent below 20 MHz absolute timing relative timing X X LDF ~exp decrease of the LDF amplitude amplitude scales as E amplitude scales as E core position radio core ≠ particle core (interference) finds the true core Benoît Revenu 19 amplitude scales as 1/d Colloque PNHE, 03/04/2014 Sudden death: PSD strong dependence to daxis shape independent on dcore! signal below 20 MHz Benoît Revenu ground 20 Colloque PNHE, 03/04/2014 Sudden death: PSD 200 m 100 m »E» @mV m-1 MHz-1D 100.0 50.0 Á Ê Á Ê Á Á Á Ê 400 m Á 10.0 Á Ê Á Ex 800 m 200 ground Á 800 khz Á Á 500 m Á Á Á Á 3 MhzÁ Á 1/d 1.0 Benoît Revenu Á Á Ê 5.0 0.5 Á 300 m Ê 20 M hz Ê p( -d /d 0) 900 m Ê 600 d @mD 400 21 700 m Ê 800 1000 m 1000 Colloque PNHE, 03/04/2014
