GLASTGLASTHiroshima University, ISAS

Cosmic-Ray Source Generator

Y.Fukazawa (Hiroshima U)

M.Ozaki(ISAS)

T.Mizuno(Hiroshima U)

S.Hirano(Hiroshima U)

T.Kamae(Hiroshima U/SLAC)

GLASTGLASTHiroshima University, ISAS

Cosmic-Ray Source Generator is required for

・ Balloon Flight Calibration

to predict a counting rate of π0 decay Gamma-ray and Background

・ Science Analysis after launch

to simulate and estimate the onboard background

study of diffuse gamma-ray emission

detection of faint gamma-ray sources

especially for

(Simulator)

GLASTGLASTHiroshima University, ISAS

Cosmic-Ray

accelerated by young SNRs, Pulsars, or other sites

modulated by Solar Wind

cut-off by magnetic field of the Earth

Generation of secondary components in the Air

inject into satellites or balloons

become the residual background by primary electrions or secondary particles and gamma-rays

propagate in the interstellar space

GLASTGLASTHiroshima University, ISAS

ProtonsAMS Measurements ….. Primary and Secondary

for various geomagnetic latitude

GLASTGLASTHiroshima University, ISAS

40E-2.79exp(-(E/20)-0.1-(E/3.96)-2.5)

3x10-3E-2.5exp(-(E/0.16)-1)

Primary

Secondary

GLASTGLASTHiroshima University, ISAS

ElectronsInformation is not so enough as protons

Primary Electrons

Komori et al. 1999 Verma et al. 1967

Secondary

GLASTGLASTHiroshima University, ISAS

0.723(E+1.1)-3.33x((E+mc2)2-(mc2)2)/((E+mc2+(1.1)2)/(1+(E/4.27)-12.0

0.028E-1.44/(1+(E/0.90)1.35) … re-entrant0.073E-1.29/(1+(E/0.90)1.50) … splash

Primary

Secondary

Solar modulation formula

geomagnetic cutoff

Komori 1999

Verma et al. modified

(Gleeson and Axford 1968)

GLASTGLASTHiroshima University, ISAS

Incident Angle Distribution(1+0.6sin(theta)) sin(theta)d(theta)

Pimary … theta<90°

GLASTGLASTHiroshima University, ISAS

Further developements …..

Support arbitral solar modulation and geomagnetic cutoff.Include Helium and other ions.

Improve the incident angle distribution (theta, phi).

Parallel StudiesResidual background due to the cosmic-rays

Improve the secondary components (intensity etc)

Current StatusSupporting the Balloon Flight experiments (various parameters are fixed for the balloon).

Summary

GLASTGLASTHiroshima University, ISAS

GLASTGLASTHiroshima University, ISAS

GLASTGLASTHiroshima University, ISAS