HEAD2010 1March 3, 2010

Electron & Positron Observation

Evolution of the UniverseDark Matter Origin

水素、ヘリウム４%

暗黒エネルギー暗黒エネルギー暗黒物質暗黒物質

重元素0.03%

ニュートリノ0.3%

星0.５%

暗黒物質25%

暗黒エネルギー暗黒エネルギー暗黒物質暗黒物質

重元素0.03%

ニュートリノ0.3%

星0.５%

暗黒物質25%

暗黒エネルギー70%

宇宙の質量構成比宇宙の質量構成比

水素、ヘリウム４%

水素、ヘリウム４%

暗黒エネルギー暗黒エネルギー暗黒物質暗黒物質

重元素0.03%

ニュートリノ0.3%

星0.５%

暗黒物質25%

暗黒エネルギー暗黒エネルギー暗黒物質暗黒物質

Heavy Element0.03%

Neutrino0.3%

Star0.5%

Dark Matter2 ３ %

Dark Energy7 ３ %

Constitutes of the Universe

Hydrogen 、Helium４%

( ) ⅰ 　 Monoenergetic: Direct Production of e+e- pair（ⅱ）　 Uniform ： Production via Intermediate

Particles（ⅲ）　 Double Peak ： Production by Dipole

Distribution via Intermediate Particles

Production Spectrum

⇒Mχ

Annihilation of Dark Matter （ WIMP)χχ→e+,e-

Production Spectrum（ Power Law Distribution ＋ Cutoff ）

Shock Wave Acceleration in SNR Acceleration in PWN

Astrophysical Origin

⇒

dN/dE E-2exp(-E/Ec)

Log(E)

Log(

dN/d

E)

Ec

↑

Propagation in the Galaxy• 　 Diffusion Process• 　 Energy Loss 　　 　　 dE/dt =-bE2

（ Syncrotron ＋ Inverse Compton ）

⇒

⇒

• 　 +/- or K+/- +/- e+/-

e++e-

HEAD2010 2March 3, 2010

220

3 2 3

1 2

1

, ~ 2

diffd dee

diff

diff e e

qf bt e

d

d t D t

16 1 1

1 328 2 1

~10 GeV s

~ 5.8 10 cm s 14GeV

-

ee

b

D

e± Propagation

2 2, , , ,e e e ee

f t x D f b f q t xt

For a single burst with

Atoyan 95, Shen 70Kobayashi 03

eq

cut ~1bt

Power law spectrum

DiffusionEnergy loss byIC & synchro.

Injection

← B/C ratio

(F0: E3 x Flux at 3TeV)

March 3, 2010 HEAD2010 3

A Naïve Result from Propagation T (age) = 2.5 X 105 X (1 TeV/E) yr R (distance) = 600 X (1 TeV/E)1/2 pc

1 TeV Electron Source: Age < a few105 years very young comparing to ~107 year at low energies Distance < 1 kpc nearby source

Source (SNR) Candidates : Vela Cygnus Loop Monogem

Unobserved Sources?

GALPROP/Credit S.Swordy

1 GeV Electrons 100 TeV Electrons

HEAD2010 4March 3, 2010

Model Dependence of Energy Spectrum and Nearby Source Effect

Ec=∞ 、 ΔT=0 yr, Do=2x1029 cm2/s Do=5 x 1029 cm2/s

Ec= 20 TeV Ec=20 TeV 、 ΔT=1-104 yr

Kobayashi et al. ApJ (2004)

HEAD2010 5March 3, 2010

We are waiting for much more study by ATIC, PAMELA, Fermi-LAT, HESSand 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-TeV to the trans-TeV 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 m2srday ( ~ FERMI-LAT). The proton rejection power is comparable to 105 , and does not depend

largely on energies .

It should be a dedicated detector for electron observation in space.

Calorimetric Electron Telescope (CALET) is proposed.

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.

HEAD2010 6March 3, 2010

CALET Overview Observation: Electrons : 1-10,000 GeV Gamma-rays : 10-10,000 GeV (GRB

>100MeV) + Gamma-ray Bursts : 7 keV-20 MeV Protons, Heavy Nuclei: several 10 GeV- 1000 TeV ( per particle) Solar Particles and Modulated Particles in Solar System: 1-10 GeV (Electrons)

Instrument: High Energy Electron and Gamma- Ray Telescope Consisted of : - Imaging Calorimeter (Particle ID, Direction) Total Thickness of Tungsten (W) ：　 3 X0

Layer Number of Scifi Belts ： 8 Layers ×2(X,Y)

- Total Absorption Calorimeter (Energy Measurement, Particle ID) PWO 　 20mm ｘ 20mm ｘ 320mm　 Total Depth of PWO ： 27 X0 (24cm)

- Silicon Pixel Array (Charge Measurement up in Z=1-35) Silicon Pixel 11.25mmx11.25mmx0.5mm 2 Layers with a coverage of 540x540 cm2

SIA 120

TASC

TASC-FEC PD

IMC

20

156.5

240

320

712

100

IMC-FEC

MAPMT

32

95

SIAElectronics

448

540

SIA 120SIA 120

TASC

TASC-FEC PD

IMC

20

156.5

240

320

712

100

IMC-FEC

MAPMT

32

95

SIAElectronics

448

540

TASC

TASC-FEC PD

IMC

20

156.5

240

320

712

100

IMC-FEC

MAPMT

32

95

IMC-FEC

MAPMT

32

95

SIAElectronics

448

540

HEAD2010 7March 2, 2010

CALET Performance for Electron Observation

SIA

IMC

TASC

Electron 100 GeV

Electron 1 TeV

GeometricalFactor(Blue Mark)

DetectionEfficiency

Energy Resolution

~2%See Poster for details( Akaike et al.)

HEAD2010 8March 3, 2010

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.

CALET System Design

＃９Calorimeter

Gamma-ray Burst MonitorStar Tracker

Mission Data Controller

Field of View (45 degrees from the zenith)

JEM/EF & the CALET Port

CALET Payload

Weight : 483.5 kgPower Consumption: 313W

March 3, 2010 HEAD2010 9

CALET

HTV

HTV

ISS

Approach to ISS

Pickup of CALET

H2-B Transfer Vehicle （ HTV)

Launching of H-IIB RocketSeparation from H2-B

Launching Procedure of CALET

CALET

HEAD2010 10March 2, 2010

Electron Observation (5 years) 　

Vela

Expected Anisotropy from Vela SNR

Expected Flux > 1000 827 644

~10% @1TeV

Monogem Cygnus Loop

11

Proton and Nucleus Observation （ 5years)

O

MgNe

FeSi

C

CREAM

2ry/ 1ry ratio ( B/C) Energy dependence of diffusion constant: D ~ Eδ

Observation free from the atmospheric effect up to several TeV/n

Nearby Source Model (Sakar et al.)Leaky Box Model

HEAD2010 12March 3, 2010

Comparison of Detector Performance for Electrons

Detector Energy Range(GeV)

Energy Resolution

e/p Selection Power

Key Instrument(Thickness of CAL)

SΩT（ m ２

srday)PPB-BETS(+BETS)

10 -1000 13% @100 GeV

4000(> 10 GeV)

IMC: (Lead: 9 X0 )

~0.42

ATIC1+2(+ ATIC4)

10 -a few 1000

<3% ( >100

GeV)

~10,000 Thick Seg. CAL (BGO: 22 X0)+ C Targets

3.08

PAMELA 1-700 5%@200 GeV

105 Magnet+IMC(W:16 X0)

~1.4(2 years)

FERMI-LAT 20-1,000 5-20 %(20-1000

GeV)

103-104

(20-1000GeV)

Energy dep. GF

Tracker+ACD+ Thin Seg. CAL

(W:1.5X0+CsI:8.6X0)

300@TeV(1 year)

AMS 1-1,000(Due to Magnet)

～ 2.5 ％＠ 100 GeV

104

(x 102 by TRD)

Magnet+IMC+TRD+RICH(Lead: 17Xo)

~100(?)(1year)

CALET 1-10,000 ~2%(>100 GeV)

～ 105 IMC+Thick Seg. CAL(W: 3 Xo+ PWO : 27

Xo)

220(5 years)

CALET is optimized for the electron observation in the tran-TeV region, and the performance is best also in 10-1000 GeV.

March 3, 2010 HEAD2010 13

A New Technology 　 and Space Experiments after CALETThe Cosmic Ray Electron Synchrotron Telescope (CREST)　　　　　　　　　　　　　　　　　　　　　　　　　　 (ICRC 2009, S.Nutter et al.)CREST payload for Ballooning:40 days at 4 g/cm2 in Antarctica

Challenging New Technology:Synchrotron X rays from electron

Expected electron detection efficiency Very large

acceptance: Vela detection up to 10 TeV (~ a few TeV for HESS ) High Threshold: E> 2 TeV Poor energy

resolution : ~ a factor of two

32x32 BaF2 Crystals(40% coverage)

2.4 m

Ex > 30 keV

TANSUO (J.Chang et al.)

HEPCaT as part of OASIS (J.W. Mitchell et al.)

Hodoscope + BGO Calorimeter

SΩ~0.4 m2 sr

SΩ~2.5 m2 sr

Sampling Silicon-W Calorimeter + Secondary Neutron Detector

HEAD2010 14March 3, 2010

The electron measurement over 1 TeV can bring us very important information of the origin and propagation of cosmic-rays 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-TeV region.The CALET has capabilities to observe the electrons up to 10 TeV , gamma-rays in 10GeV- 10TeV , proton and heavy ions in several 10 GeV - 1000 TeV, 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.

Summary and Future Prospect

HEAD2010 15March 3, 2010

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.KamiokaICRR, University of Tokyo: Y.Shimizu, M.TakitaYokohama National University: Y.Katayose, M.ShibataHirosaki University: S. Kuramata, M. IchimuraTokyo Technology Inst.: T.Terasawa, Y. TunesadaNational 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.SasakiLouisiana State University: M. L. Cherry, T. G. Guzik, J. P. WefelWashington University in St Louis: W. R. Binns, M. H. Israel, H. S. KrawzczynskiUniversity 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.VannucciniUniversity of Pisa and INFN: 　 C.Avanzini, T.Lotadze, A.Messineo, F.Morsani

Purple Mountain Observatory: 　 J. Chang, W. Gan, J. YangInstitute of High Energy Physics: Y.Ma, H.Wang,G.Chen