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Good news from BATSE-TASC data to MILAGRO. Searching for a GRB second spectral component. magda. Detectors BATSE-LAD EGRET-TASC. no position determination E: 1-200 MeV 1,2,4,16,32 s t resolution 66% dead time. biggest GRB catalog position determination E: 25keV-2MeV
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Good news from BATSE-TASC data to MILAGRO Searching for a GRB second spectral component magda
DetectorsBATSE-LAD EGRET-TASC • no position determination • E: 1-200 MeV • 1,2,4,16,32 s t resolution • 66% dead time • biggest GRB catalog • position determination • E: 25keV-2MeV • 16-64ms t resolution magda
Epeak and b are better determined Flux (photons keV cm-2 s-1) GRB910503 Energy (keV) magda
GRB941017 Time after BATSE’s trigger(sec) magda
GRB941017 • There is a second spectral component • observed by 2 different detectors • duration > 150sec • gamma = -1 • no peak seen • no temporal evolution • fluence = 4* fluenceBATSE magda
GRB940217, Hurley 94, SSC 85, Harris 1998 GRB940417, Atkins 2000, SSC GRB941017, Gonzalez 03 magda
Synchrotron Ne(ge) ge ge Es FIC SSC Fs Synchrotron ge Es EIC Understanding… magda
INVERSE COMPTON SCATTERING E’IC = E’/(1+(E’/mc2)(1-cos f) Doppler shift EIC = ge2 ES E= E’ge(1 - bcos F’) = (103)2 105 eV E’=Ege(1 + bcos F) = 100 GeV -up Gamma = -1 in nFn Gamma’ = -1+2=1 For SSC LIC/LS = EIC/ES = 106!!!!! For IC temporal synchrotron part evolution IC part will have same temporal evolution !!! magda
HADRON CASCADES p po p 2g p g p p+ e +ne nmnm Sources of photons: p synchrotron po decay e+ synchrotron magda
A second spectral component exists. There is not good enough theory that could explain it. It may or may not extend to MILAGRO energies It seems to last hundreds of seconds MILAGRO may see it if we search at lower energies in long time scales Need to improve our hadron rejection for lower energies. magda