CALET-CALによる ガンマ線観測初期解析 早大理工研，早大先進理工A，CRESST/USRA/GSFCB, 神奈川大工C，JAXAD,青学大理工E, 名大ISEEF 浅岡陽一，鳥居祥二，小澤俊介A ，山口優幸A, 赤池陽水B，清水雄輝C ，田村忠久C ， 中平聡志D, 吉田篤正E, 坂本貴紀E, 川久保雄太E, 山岡和貴F, 他CALETチーム 2017/3/18 春の物理学会 @ 大阪大学 18aK21-1

CALET System Overview (CAL) (*) JEM stands for Japan Experiment Module x-ray to soft-gamma-ray transient (*) JEM stands for Japan Experiment Module

CALET-CAL Detector Fully active thick calorimeter (30X0) optimized for electron spectrum measurements well into TeV region 448mm Charge Detector CHD plastic scintillator hodoscope, absolute charge measurement (including charge zero) Imaging Calorimeter IMC SciFi + tungsten plate (3X0), reconstruction of arrival direction and initial shower development Total Absorption Calorimeter TASC PWO hodoscope (27X0), energy measurements and particle identification 1TeV electron shower is fully contained in TASC

CALET-CAL Shower Imaging Capability (MC) gamma electron pion we can use the shower shape difference to separate electrons and protons and proton rejection factor of ... gamma-rays can be identified by requiring zero charge at incidence. Proton rejection power of 105 can be achieved by taking advantage of shower imaging capability of IMC and TASC Angular resolution of ~0.2o for 10GeV gamma rays

CALET Scientific Objectives While CALET is optimized for observation of TeV electrons, the instrument is sensitive to gamma-rays, protons and nuclei. Science Objectives Observation Targets Nearby Cosmic-ray Sources Electron spectrum in trans-TeV region Dark Matter Signatures in electron/gamma energy spectra Origin and Acceleration of Cosmic Rays p-Fe over several tens of GeV, Ultra-heavy ions Cosmic-ray Propagation in the Galaxy B/C ratio up to several TeV/nucleon, Diffuse gamma-ray observation up to TeV Solar Physics Electron flux below 10 GeV Gamma-ray Transients X-rays/Gamma-rays in 7 keV－20MeV in CGBM and GeV gamma-rays in CAL

Overview of CALET Trigger System

ISS Orbit and CALET Operations

Accumulation of Observational Live Time HE Trigger LE Gamma-Ray Trigger 1.42e6/7.44e6 = 19% Live time fraction of 85% achieved Now more than 104 hours! From 2016/08, 19% of total live time is covered by LE gamma-ray trigger

Objectives of CALET Gamma-Ray Observation Diffuse Component => High energy region Galactic Extragalactic Point Source Calibration of pointing accuracy Confirmation of angular resolution Cross check of energy measurements/efficiency Transient Object GRB Gravitational wave Other transients

Objectives of CALET Gamma-Ray Observation Diffuse Component => High energy region Galactic Extragalactic Point Source Calibration of pointing accuracy Confirmation of angular resolution Cross check of energy measurements/efficiency Transient Object GRB Gravitational wave Other transients Statistics is the KEY We will focus on this topic by utilizing 10,000 hours of flight data

Gamma Ray Event Selection = Electron Selection Cut + Gamma-ray ID Cut w/ Lower Energy Extension 100 GeV Event Examples gamma-ray electron proton Charge Z=0 Charge Z=1 Electromagnetic Shower Hadron Shower well contained, constant shower development larger spread

Gamma Ray Event Selection = Electron Selection Cut + Gamma-ray ID Cut w/ Lower Energy Extension 100 GeV Event Examples gamma-ray electron proton Charge Z=0 Charge Z=1 E<10GeV: Maximum Energy Deposit in CHD Reconstructed Energy [GeV] CHD Maximum Energy Deposit [MIP] MC: Gamma-Ray MC: Proton Electromagnetic Shower Hadron Shower well contained, constant shower development larger spread

Gamma Ray Event Selection = Electron Selection Cut + Gamma-ray ID Cut w/ Lower Energy Extension 100 GeV Event Examples gamma-ray electron proton Charge Z=0 Charge Z=1 E>10GeV: Maximum Energy Deposit in CHD and IMC associated w/ Track MC: Gamma-Ray MC: Proton well contained, constant shower development larger spread

Sensitivity Improvements Larger acceptance requires CHD and TASC-X1 to avoid too much energy leakage, 2cm margin is required at TASC-X1 Accurate energy reconstruction geometry conditions are sub-divided in terms of leaking energy energy correction factor is estimated in each sub-divided geometry condition.

LE Trigger (w/ Enlarged Acceptance) PRELIMINARY

FOV cut FOV cut is very important to avoid secondary gamma-rays especially in LE region LE Trigger blue circles: 45 deg and 60deg. by JAXA

LE Trigger (w/ FOV cut) PRELIMINARY Crab Geminga CTA102 (transient) Vela Exposure is limited to low latitude region => |declination| > 60 is hardly seen.

LE Trigger (October 2016) PRELIMINARY Geminga CTA102 (transient) Exposure is limited to low latitude region => |declination| > 60 is hardly seen.

LE Trigger (November 2016) PRELIMINARY Geminga CTA102 (transient) Exposure is limited to low latitude region => |declination| > 60 is hardly seen.

LE Trigger (December 2016) PRELIMINARY Geminga CTA102 (transient)

LE Trigger (January 2017) PRELIMINARY Geminga CTA102 (transient)

LE Trigger (in Galactic Coordinate) PRELIMINARY

comparison with fermi TO BE REVISED

comparison with diffuse model TO BE REVISED

comparison with fermi TO BE REVISED

comparison with diffuse model TO BE REVISED

HE Trigger in Galactic Coordinates PRELIMINARY VELA Vela and Crab are identified.

comparison with fermi

comparison with diffuse model

finer binning

comparison with fermi

comparison with diffuse model

Summary & Prospects Using the full set of CALET data from Oct. 2015 to Feb. 2017, gamma-ray analysis was performed and gamma-ray sky was obtained in LE and HE trigger mode. Geminga, Crab, Vela, and AGN flare (CTA-102) are clearly identified. Sensitivity was confirmed to be consistent with diffuse expectation. Significant sensitivity improvements in lower and higher energy region is expected tracking in LE gamma-ray identification in HE Automated pipeline to search for gamma-ray transient was also developed and is being implemented.

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Objectives of CALET Gamma-Ray Observation Diffuse Component => High energy region Galactic Extragalactic Point Source Calibration of pointing accuracy Confirmation of angular resolution Cross check of energy measurements/efficiency Transient Object GRB Gravitational wave Other transients

探索感度

GRB Simulation データはできている Quaternion の扱いに問題 フラックスと検出できたことを示す

CGBMトリガーによる他観測と同期したGRB観測(19回) MDCTime Date GRB 1130963026 2015/11/07 20:24:54.771 GRB151107B 1133744236 2015/12/10 00:59:20.485 GRB151210B 1133919001 2015/12/12 01:32:04.734 GRB151212B 1135105601 2015/12/25 19:09:10.34 GRB151225A 1135228276 2015/12/27 05:13:48.86 GRB151227B 1135593314 2015/12/31 10:37:53.15 GRB151231A 1135644074 2016/01/01 00:43:54.044 GRB160101A 1136155362 2016/01/06 22:45:34.70 GRB160106A 1136240273 2016/01/07 22:20:43.20 GRB160107A 1137115370 2016/01/18 01:25:56.902 GRB160118A 1140256490 2016/02/23 09:58:59.51 GRB160223B 1142170831 2016/03/16 13:45:16.79 GRB160316A 1142870018 2016/03/24 15:58:37.99 GRB160324A 1144131613 2016/04/08 06:25:37.40 GRB160408A 1145113851 2016/04/19 15:16:35.41 GRB160419A 2016/04/22 11:59:08.28 GRB160422A 1146752776 2016/05/08 14:32:31.73 GRB160508A 1146819154 2016/05/09 08:58:51.21 GRB160509A 1148208864 2016/05/25 10:54:20.251 GRB160525C

内容(案) CALET Observation Summary GRB counterpart search Statistics Operation Mode HE LE gamma ray Calibration GRB counterpart search 感度評価 w/ GRB simulation (田中) 探索結果 (semi) Real Time Search System (山口) Improvement CC Track => diffuse (佐藤)

CGBMトリガーによる他観測と同期したGRB観測(19回) MDCTime Date GRB 1130963026 2015/11/07 20:24:54.771 GRB151107B 1133744236 2015/12/10 00:59:20.485 GRB151210B 1133919001 2015/12/12 01:32:04.734 GRB151212B 1135105601 2015/12/25 19:09:10.34 GRB151225A 1135228276 2015/12/27 05:13:48.86 GRB151227B 1135593314 2015/12/31 10:37:53.15 GRB151231A 1135644074 2016/01/01 00:43:54.044 GRB160101A 1136155362 2016/01/06 22:45:34.70 GRB160106A 1136240273 2016/01/07 22:20:43.20 GRB160107A 1137115370 2016/01/18 01:25:56.902 GRB160118A 1140256490 2016/02/23 09:58:59.51 GRB160223B 1142170831 2016/03/16 13:45:16.79 GRB160316A 1142870018 2016/03/24 15:58:37.99 GRB160324A 1144131613 2016/04/08 06:25:37.40 GRB160408A 1145113851 2016/04/19 15:16:35.41 GRB160419A 2016/04/22 11:59:08.28 GRB160422A 1146752776 2016/05/08 14:32:31.73 GRB160508A 1146819154 2016/05/09 08:58:51.21 GRB160509A 1148208864 2016/05/25 10:54:20.251 GRB160525C

HE Trigger Events

HE Trigger Events

HE Trigger Events

E>30GeV

E>30GeV

E>30GeV

E>30GeV

CALET Gamma Rays Candidates w/ HE Trigger