CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico CODALEMA A Cosmic Ray Radio Detection Array Didier Lebrun, LPSC Grenoble & CODALEMA Collaboration

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico CODALEMA Didier Lebrun, LPSC Grenoble Project Observation of Transient Events with Digital Radio astronomy Stellar Solar & Planetary (icrc0337) Atmosphere Cosmic Ray Radio Detection Telescope deployment (icrc0161) Study of Radio emission (icrc0460) Large Array R&D (icrc0339) Collaboration ~25 persons from 8 French Labs Particle & Cosmic Ray Physics SUBATECH, Nantes LAL, Orsay LPSC, Grenoble Radio Astronomy LESIA, Observatoire de Paris USN, Nançay LAOB, Besançon Atmospheric Physics LPCE, Orleans Electronics ESEO, Angers

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico EAS Radio Detection Didier Lebrun, LPSC Grenoble 40 years after first successfull experiment in Jodrell Bank  EAS Radio Detection revisited since 2004 from o LOPES in Karlsruhe o CODALEMA in Nançay  New Phase: Characterization of EAS Radio emission CODALEMA : 3 years funded ANR program since 2006 To Develop and Deploy for cosmic ray studies:  Ground Particle Detector Array to trig and calibrate radio signal  New Radio Antenna Array from huge log antennas to small linear antennas COsmic ray Detection Array with Logarithmic Electro-Magnetic Antennas Linear

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Radio Astronomy Observatory in Nançay Didier Lebrun, LPSC Grenoble Large Radio Telescope Decametric Network Heliograph station CODALEMA

A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Array Lay Out Didier Lebrun, LPSC Grenoble

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico DAQ Didier Lebrun, LPSC Grenoble T TRIGGER HG 600 ns Gate All detectors Wired to Central DAQ “MATACQ” Digitalizing Cards 1 Gs/s 12bits, 2560 points. 1V max 13 Scintillators 2 PMTs High Gain and Low Gain per station Clock 16 Antennas 14 EW+1 Cross

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Scintillator Array : Data processing Didier Lebrun, LPSC Grenoble Signal analysis Calibration with VEM Arrival Direction: TOF/stations Arrival time: Plane shower front Shower Size : Integrated pulse/station /VEM LDF fit with NKG function Shower Core: Internal ( /external) Trigger select:Central counter>surroundings)  distribution

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico ScintillatorArray :EAS Energy Estimation Didier Lebrun, LPSC Grenoble ‘Vertical Equivalent Shower Size’ Use of Constant Intensity Cut CIC Method From simulations (AIRES) : E= N  E/E = eV Scintillator Array Energy Spectrum Internal Events log E (eV) sec  bins N(  ) Intensity counts

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Radio Array : Active Dipole Antennas Didier Lebrun, LPSC Grenoble Low Noise Amplifier ASIC BiCMOS 0,8  High Input Impedance BW(3dB)=200MHz G LNA =34 dB Input Noise: 1.3 nV/ V Hz Z input = 10 pF Transmission S~1 (<100 MHz) Short Dipole L< Short Dipole L< - ~Isotropic(  < Res ) - Smooth response L. Effective L ength V oc = L.E Active Low induced current - Needs amplifier Z Pure capacitive -Matching Load L=1.2 m h=1.0 m res ~ 115 MHz Gain (  ) 50 MHz HPBW=60° Eff. Length (dB meter) at Zenith L= L. S. G LNA MHz

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Calibration: Interferometric measurement with sky source Didier Lebrun, LPSC Grenoble Correlation Dipole- Decametric Array during Cas A Transit See ICRC339 Poster, B.Revenu

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Radio Frequency Background on Site Didier Lebrun, LPSC Grenoble LNA Noise Analyzer noise FM Expected Sky Noise With Dipole L Filter BW

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Tagging Antennas Digital Filtering in MHz Band Didier Lebrun, LPSC Grenoble Scintillator Array Trigger Event  =43°  =39° Labelled ‘external’ logE~18.3 Associated Radio event  =39.5°  =32° Scint/Radio wave front  = 6.5°  t = 7.5 ns

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico EAS Radio Event Validation Didier Lebrun, LPSC Grenoble Particle and Radio Shower Front Coincidence

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Signal in Filtered band and Spectrum in Full band Didier Lebrun, LPSC Grenoble Raw EAS Event Random Trigger 0 Frequency 200 MHz milli-Volts Signal amplitude analysis in filtered band [23-85] Spectral dependence information in Full band ( analysis in progress ) Log (Power/MHz) arb.units nanoseconds

CODALEMA A Cosmic Ray Radio Detection Array ICRC 2007, 3-11 July Merida, Mexico Conclusions Didier Lebrun, LPSC Grenoble CODALEMA A Radio Detection Array with Active Dipole Antennas, Coupled with a Scintillation Counter Array was described. CODALEMA is now running in Nançay to study EAS radio emission at energy E~10 17 eV Results will be presented in icrc0420 CODALEMA further developments include More antennas in NS for Polarization studies (on going this year) Increase ground array size (on going this year) New semi-autonomous antennas (2008, embedded DAQ, not self-powered) Self-triggering radio system Solitary Antenna system R&D for very large arrays