Electron Observation : Past, Present and Future

1. Electron Observation : Past, Present and Future S.Torii : Waseda University (Japan) Rome PAMELA Workshop11.05.2009

2. Model Dependence of Nearby Source Effect Kobayashi et al. ApJ 2003 Ec=∞、 ΔT=0 yr, Do=2x1029 cm2/s at 1 TeV Do=5 x 1029 cm2/s Ec= 20 TeV Ec=20 TeV、 ΔT=1-104 yr We need a precise measurement at TeV energies to confirm the near-by sources for all of the models.

3. Calorimetric Electron Telescope (CALET) is proposed. • As a conclusion, • we will wait for much more study by ATIC, PAMELA, FERMI-LAT, H.E.S.S. • and a new experiment in space, AMS-02. • Moreover, • we need accurate measurements up to 10 TeV for detection of nearby • sources and ,naturally ,very-high-statistics observation for Dark Matter search in sub-TeV region with a detector which has performance: • The systematic errors including GF is less than a few %. • The absolute energy resolution is less than 5 % ( ~ATIC). • The exposure factor is as large as several 100 m2srday ( ~ FERMI-LAT). • Possibly, the performance does not depend on energies. • It should be a dedicated detector for electron observation in space.

4. γ AGN e+ Pulsar SNR P χ χ e γ Pair Annihilation e- γ CALET Cosmic Ray Sources Dark Matter International Space Station Japanese Experiment Module (Kibo) CALorimetric Electron Telescope A Dedicated Detector for Electron Observation in 1GeV – 10,000 GeV

5. International Collaboration Team Waseda University：　S. Torii, K.Kasahara, S.Ozawa, S.Udo, N. Hasebe, M.Hareyama, N.Yamashita, O.Okudara , S.Kodaira JAXA/ISAS：　J. Nishimura, T. Yamagami , Y. Saito H. Fuke, M.Takayanagi, H. Tomida, S. Ueno, K.Ebisawa Kanagawa University： 　 T. Tamura, N. Tateyama, K. Hibino, S.Okuno Aoyama Gakuin University ：　A.Yoshida, T.Kobayashi, K.Yamaoka, T.Kotani Shibaura Institute of Technology：　K. Yoshida , A.Kubota, E.Kamioka ICRR, University of Tokyo ：　　Y.Shimizu, M.Takita, T.Yuda Yokohama National University：Y.Katayose, M.Shibata Hirosaki University:S. Kuramata, M. Ichimura,T okyo Technology Inst.:T.Terasawa, Y. Ichisada National Inst. of Radiological Sciences : Y. Uchihori, H. Kitamura Rikkyo University: H. Murakami Kanagawa University of Human Services : Y.Komori Saitama University: K.Mizutani Shinshu University : K.Munekata Nihon University: A.Shiomi NASA/GSFC:J.W.Mitchell, A.J.Ericson, T.Hams, A. A.Moissev, J.F.Krizmanic, M.Sasaki Louisiana State University:M. L. Cherry, T. G. Guzik, J. P. Wefel Washington University in St Louis: W. R. Binns, M. H. Israel, H. S. Krawzczynski University of Denver: J.F.Ormes University of Siena and INFN:P.S.Marrocchesi , M.G.Bagliesi, G.Bigongiari, A.Caldaroe, M.Y.Kim, R.Cesshi, P.Maestro, V.Millucci , R.Zei University of Florence and INFN:O. Adriani, P. Papini, L. Bonechi, E.Vannuccini University of Pisa and INFN:C.Avanzini,T.Lotadze, A.Messineo, F.Morsani Purple Mountain Observatory:J. Chang, W. Gan, J. Yang Institute of High Energy Physics:Y.Ma, H.Wang,G.Chen

6. JEM/EF CALET CALET Overview • CALET Mission Concept • Observation: • Electrons in 1GeV - 20 TeV • Gamma-rays in 20 MeV -10TeV + Gamma-ray Bursts in 7 keV - 20MeV • P-Fe in several 10GeV - 1000 TeV • Launch: HTV: H-IIB Transfer Vehicle • Attach Point on the ISS: Exposed Facility of Japanese Experiment Module (JEM-EF) • Life Time: 3(min.) - 5 years • Mission Status Phase Afor Launch around 2013 in Plan • CALET Payload • High Energy Electron and Gamma- Ray Telescope Consisted of - Imaging Calorimeter - Total Absorption Calorimeter • Weight: 1500 kg • Geometrical Factor: ~0.7 m2sr • Power Consumption: 640 W • Data Rate: 300 kbps

7. CALET CALET ISS HTV HTV Launching Procedure of CALET H-IIA Transfer Vehicle（HTV) CALET launched by HTV Pickup of CALET Approach to ISS Separation from H-II Launching of H-II Rocket

8. GBM SACS VSC SIA MDP IMC TASC Schematic Structure of the CALET Payload SACS:Scitillator Anti-Coincidence System SIA: Silicon Pixel Array IMC: Imaging Calorimeter TASC: Total Absorption Calorimeter GBM: Gamma-Ray Burst Monitor VSC: Visual Sky Camera MDP: Mission Data Processor

9. Details of Each Component TASC IMC SACS(ACD) SIA Co-PI: Pier S. Marrocchesi • Silicon Pixel Array x 2 layers ( Pixel ~1cmx 1cm) • Charge resolution: 0.1e for p, 0.35e for Fe • Segmented Plastic Scintillators for Anti-Coincidence

10. Examples of Simulation Events

11. Vela 10,000 years 820 ly Chandra Anisotropy ROSAT Cygnus Loop 20,000 years 2,500 ly Monogem 86,000 years 1,000 ly • Possible Nearby Sources • T< 105 years • L< 1 kpc Purposes of ElectronObservation Search for the signature of nearby HE electron sources (believed to be SNR) in the electron spectrum above ~ TeV Search for anisotropy in HE electron flux as an effect of the nearby sources. Precise measurement of electron spectrum above 10 GeV to define a model of accele- ration and propagation. Observation of electron spectrum in 1~10 GeV for study of solar modulation Expected Electron Spectrum by the CALET Observation for 3 years (~ 1000 m2 sr day) Nearby Pulsars or Dark Matter W=1048 erg/SN I(E)=I0E-α Ｎ=1/30yr D=D0(E/TeV)0.3

12. IMC > TASC CALET Performance by Simulation Geometrical Factor Geometry for Analysis (C) (A) Angular Resolution Energy Resolution

13. RE = FE = Rejection Power against Background Protons 4 TeV Electron 7.;8 TeV Proton Rejection Power for survival of 95 % electrons @ 4 TeV ~ 105 ( ~1 % residual protons) @100 GeV ~ 4x 105 ( ~ 0. 1 %) 1.27 M events of protons A little effect on electron flux by uncertainties in simulation model

14. Electron(+Postron) Detector and Performance *) Future Project