Electron Positron Observation Astrophysical Origin Production Spectrum Acceleration
Electron & Positron Observation Astrophysical Origin Production Spectrum Acceleration in PWN Log(d. N/d. E) Shock Wave Acceleration in SNR (Power Law Distribution +Cutoff) d. N/d. E E-2 exp(-E/Ec) Propagation in the Galaxy • Diffusion Process • Energy Loss d. E/dt =-b. E 2 (Syncrotron+Inverse Compton) • +/- or K+/- e+/- ⇒ ⇒ ↑ Ec e++e. Evolution of the Universe Dark Matter Origin Constitutes of 宇宙の質量構成比 the Universe 暗黒エネルギー 暗黒物質 Heavy 重元素Element 重元素 0. 03% ニュートリノ Neutrino 0. 3% ニュートリノ 0. 3% 星 Star 0. 5 % 5% 星 0. 0. 5% Hydrogen、 水素、 Helium ヘリウム 水素、 4% ヘリウム 4% 暗黒物質 Dark Matter 暗黒物質 25% 23% 25% 暗黒エネルギー Dark Energy 70% 73% March 3, 2010 ⇒ Log(E) ⇒ Annihilation of Dark Matter(WIMP) χχ→e+, e- HEAD 2010 Mχ Production Spectrum (ⅰ) Monoenergetic: Direct Production of e+e- pair (ⅱ) Uniform:Production via Intermediate Particles (ⅲ) Double Peak: Production by Dipole Distribution via Intermediate Particles 1
e± Propagation Diffusion Energy loss by IC & synchro. Injection ← B/C ratio For a single burst with Power law spectrum Atoyan 95, Shen 70 Kobayashi 03 March 3, 2010 HEAD 2010 2
A Naïve Result from Propagation T (age) = 2. 5 X 105 X 1 Ge. V Electrons (1 Te. V/E) yr R (distance) = 600 X (1 Te. V/E)1/2 100 Te. V Electrons GALPROP/Credit S. Swordy pc 1 Te. V Electron Source: n Age < a few 105 years very young comparing to ~107 year at low energies n Distance < 1 kpc nearby source Source (SNR) Candidates : Vela Cygnus Loop Monogem Unobserved Sources? March 3, 2010 (F 0: E 3 x Flux at 3 Te. V) HEAD 2010 3
Model Dependence of Energy Spectrum and Nearby Source Effect Ec=∞、 ΔT=0 yr, Do=2 x 1029 cm 2/s Do=5 x 1029 cm 2/s Ec= 20 Te. V Ec=20 Te. V、 ΔT=1 -104 yr Kobayashi et al. Ap. J (2004) March 3, 2010 HEAD 2010 4
Efforts by the new experiments for deriving the positron and electron spectra are really appreciated to open a door to new era in astroparticle physics. We are waiting for much more study by ATIC, PAMELA, Fermi-LAT, HESS and a forthcoming experiment in space, AMS-02. Moreover, We need an accurate and very-high-statistics observation for searching Dark Matter and/or Nearby Pulsars in the sub-Te. V to the trans-Te. V region with a detector which has following performance: The systematic errors including GF is less than a few %. The absolute energy resolution is as small as a few % ( ~ATIC). The exposure factor is as large as more than 100 m 2 srday ( ~ FERMI-LAT). The proton rejection power is comparable to 10 5 , and does not depend largely on energies. It should be a dedicated detector for electron observation in space. Calorimetric Electron Telescope (CALET) is proposed. March 3, 2010 HEAD 2010 5
CALET Overview p Observation: Ø Electrons : 1 -10, 000 Ge. V Ø Gamma-rays : 10 -10, 000 Ge. V (GRB >100 Me. V) + Gamma-ray Bursts : 7 ke. V-20 Me. V Ø Protons, Heavy Nuclei: several 10 Ge. V- 1000 Te. V ( per particle) Ø Solar Particles and Modulated Particles in Solar System: 1 -10 Ge. V (Electrons) p Instrument: High Energy Electron and Gamma- Ray Telescope Consisted of : - Imaging Calorimeter (Particle ID, Direction) Total Thickness of Tungsten (W) : 3 X 0 Layer Number of Scifi Belts: 8 Layers × 2(X, Y) - Total Absorption Calorimeter (Energy Measurement, Particle ID) PWO 20 mmx 320 mm Total Depth of PWO: 27 X 0 (24 cm) - Silicon Pixel Array (Charge Measurement up in Z=1 -35) Silicon Pixel 11. 25 mmx 0. 5 mm 2 Layers with a coverage of 540 x 540 cm 2 March 3, 2010 HEAD 2010 6
CALET Performance for Electron Observation Electron 100 Ge. V SIA Geometrical Factor (Blue Mark) IMC TASC Detection Efficiency Electron 1 Te. V Energy Resolution ~2% See Poster for details ( Akaike et al. ) March 2, 2010 HEAD 2010 7
CALET System Design The CALET mission instrument can satisfy the requirements as a standard payload in size, weight, power, telemetry etc. for launching by HTV and observation at JEM/EF & the CALET Port CALET Payload Star Tracker Gamma-ray Burst Monitor Calorimeter #9 Field of View (45 degrees from the zenith) Mission Data Controller Weight : 483. 5 kg Power Consumption: 313 W March 3, 2010 HEAD 2010 8
Launching Procedure of CALET H 2 -B Transfer Vehicle(HTV) ISS Pickup of CALET HTV Approach to ISS HTV Launching of H-IIB Rocket March 3, 2010 Separation from H 2 -B CALET HEAD 2010 9
Electron Observation (5 years) Expected Anisotropy from Vela SNR ~10% @1 Te. V > 1000 827 644 Monogem March 2, 2010 Expected Flux Cygnus Loop Vela HEAD 2010 10
Proton and Nucleus Observation (5 years) 2 ry/ 1 ry ratio ( B/C) Ø Energy dependence of diffusion constant: D ~ Eδ Ø Observation free from the atmospheric effect up to several Te. V/n C Ne Si O Mg Fe CREAM Leaky Box Model Nearby Source Model (Sakar et al. ) 11
Comparison of Detector Performance for Electrons CALET is optimized for the electron observation in the tran-Te. V region, and the performance is best also in 10 -1000 Ge. V. Detector Energy Range (Ge. V) Energy Resolution e/p Selection Power Key Instrument (Thickness of CAL) SΩT (m2 srday) PPB-BETS (+BETS) 10 -1000 13% @100 Ge. V 4000 (> 10 Ge. V) IMC : (Lead: 9 X 0 ) ~0. 42 ATIC 1+2 (+ ATIC 4) 10 a few 1000 <3% ( >100 Ge. V) ~10, 000 Thick Seg. CAL (BGO: 22 X 0) + C Targets 3. 08 PAMELA 1 -700 5% @200 Ge. V 105 Magnet+IMC (W: 16 X 0) ~1. 4 (2 years) FERMI-LAT 20 -1, 000 5 -20 % (20 -1000 Ge. V) 103 -104 (20 -1000 Ge. V) Tracker+ACD + Thin Seg. CAL (W: 1. 5 X 0+Cs. I: 8. 6 X 0) 300@Te. V (1 year) Energy dep. GF AMS 1 -1, 000 (Due to Magnet) ~ 2. 5% @ 100 Ge. V 104 (x 102 by TRD) Magnet+IMC +TRD+RICH (Lead: 17 Xo) ~100(? ) (1 year) CALET 1 -10, 000 ~2% (>100 Ge. V) ~ 105 IMC+Thick Seg. CAL (W: 3 Xo+ PWO : 27 Xo) 220 (5 years) March 3, 2010 HEAD 2010 12
A New Technology and Space Experiments after CALET The Cosmic Ray Electron Synchrotron Telescope (CREST) TANSUO (J. Chang et al. ) (ICRC 2009, S. Nutter et al. ) Hodoscope + BGO Calorimeter CREST payload for Ballooning: Challenging New Technology: 40 days at 4 g/cm 2 in Antarctica Synchrotron X rays from electron SΩ~0. 4 m 2 sr 2. 4 m 32 x 32 Ba. F 2 Crystals (40% coverage) Ex > 30 ke. V HEPCa. T as part of OASIS Expected electron detection efficiency Ø Very large acceptance: Vela detection up to 10 Te. V (~ a few Te. V for HESS ) Ø High Threshold: E> 2 Te. V Ø Poor energy resolution : ~ a factor of two March 3, 2010 (J. W. Mitchell et al. ) Sampling Silicon-W Calorimeter + Secondary Neutron Detector SΩ~2. 5 m 2 sr HEAD 2010 13
Summary and Future Prospect The electron measurement over 1 Te. V can bring us very important information of the origin and propagation of cosmicrays and also of the dark matter ( yet not discussed here). We have successfully been developing the CALET instrument for Japanese Experiment Module (Kibo) – Exposed Facility to extend the electron observation to the tans-Te. V region. The CALET has capabilities to observe the electrons up to 10 Te. V , gamma-rays in 10 Ge. V- 10 Te. V , proton and heavy ions in several 10 Ge. V - 1000 Te. V, for investigation of high energy phenomena in the Universe. The CALET mission has been approved by the System Definition Review (SDR) , and will proceed to the Phase B soon for launching in 2013. March 3, 2010 HEAD 2010 14
International Collaboration Team Waseda University: S. Torii, K. Kasahara, S. Ozawa, H. Murakami, Y. Akaike, T. Suzuki, R. Nakamura, K. Miyamoto, T. Aiba, M. Nakai, Y. Ueyama, N. Hasebe, J. Kataoka JAXA/ISAS: M. Takayanagi, H. Tomida, S. Ueno, J. Nishimura, Y. Saito H. Fuke, K. Ebisawa, M. Hareyama Kanagawa University: T. Tamura, N. Tateyama, K. Hibino, S. Okuno, T. Yuda 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 Yokohama National University: Y. Katayose, M. Shibata Hirosaki University: S. Kuramata, M. Ichimura Tokyo Technology Inst. : T. Terasawa, Y. Tunesada National Inst. of Radiological Sciences: Y. Uchihori, H. Kitamura KEK: K. Ioka, N. Kawanaka Kanagawa University of Human Services: Y. Komori Saitama University: K. Mizutani Shinshu University: K. Munekata Nihon University: A. Shiomi Ritsumeikan University: M. Mori 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: K. Batkov, M. G. Bagliesi, G. Bigongiari, A. Caldaroe, R. Cesshi, M. Y. Kim, P. Maestro, P. S. Marrocchesi , V. Millucci , R. Zei University of Florence and INFN: O. Adriani, L. Bonechi, P. Papini, 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 March 3, 2010 HEAD 2010 15
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