11-13 November 2019
The University of Tokyo, Kashiwa Campus
Asia/Tokyo timezone

SMILE project: all-sky MeV gamma-ray observation and dark matter survey

12 Nov 2019, 17:00
The University of Tokyo, Kashiwa Campus

The University of Tokyo, Kashiwa Campus

Institute for Cosmic Ray Research, The University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba, Japan
Contributed talk DM Astrophysics Young Scientists session


Mr Yuta Nakamura (Kyoto University)


In the MeV gamma-ray band, the observed Galactic diffuse gamma-rays has the excessive component cannot be explained by the current standard model of the Galaxy. This excess might be gamma-rays due to annihilation of MeV scale WIMP dark matter or evaporations of primordial black holes. The MeV band has the advantage over the GeV band because there is less diffuse gamma-ray background due to no $\pi ^0$ bump.
In 2018 April 7, we carried out the campaign, sub-MeV and MeV gamma-ray imaging loaded-on balloon experiment 2+ (SMILE-2+), in order to demonstrate the imaging performance of the gaseous electron tracking Compton camera (ETCC). Unlike conventional Compton cameras such as COMPTEL, ETCC uniquely reconstructs the directions of gamma-rays and realizes the noiseless gamma-ray observation even in the space environment by the particle identification and Compton kinematical test. This detector has the energy range from $200\,\mathrm{keV}$ to $5\,\mathrm{MeV}$ and the wide field of view ($3\,\mathrm{str}$). We observed the Galactic center for 8 hours and detect it with the significances of $5\,\sigma$ ($511\,\mathrm{keV}$) and $10\,\sigma$ (continuum). The sensitivity of the satellite with ETCC will reach $1\,\mathrm{mCrab}$ ($10^6\,\mathrm{sec}$, $3\,\sigma$) and the HPR of its PSF will be $5\,\mathrm{degree}$.


Kyoto University

Primary author

Mr Yuta Nakamura (Kyoto University)


Prof. Tanimori Toru (Kyoto University) Dr Atsushi Takada (Kyoto University) Dr Yoshitaka Mizumura (Kyoto University) Mr Taito Takemura (Kyoto University) Mr Kei Yoshikawa (Kyoto University) Mr Mitsuru Abe (Kyoto University) Dr Tetsuya Miumoto (Kyoto University) Dr Shinya Sonoda (Kyoto University) Dr Hidetoshi Kubo (Kyoto University) Dr Shotaro Komura (Kyoto University) Mr Tetsuro Kishimoto (Kyoto University) Mr Tomoyuki Taniguchi (Kyoto Univeristy) Mr Ken Onozaka (Kyoto University) Mr Kaname Saito (Kyoto University) Dr Shunsuke Kurosawa (Tohoku University) Dr Kentaro Miushi (Kobe University) Prof. Kenji Hamaguchi (Maryland University ) Dr Tatsuya Sawano (Kanazawa University) Dr Masayoshi Kozai (JAXA) Dr Yasuhiro Shoji (Oasaka University)

Presentation Materials