Date & Time: 2023/Sep./14 (Thu) 17:00-18:00, Venue: Zoom TV Conference System. This is an informal seminar on the formation of stars and planets. We welcome anyone interested in the subject.

Title: Roles of Cosmic-Rays in Astrophysics: The History of Our Galaxy 

Speaker: 霜田 治朗 (宇宙線研究所)

Abstract: We study the long-term evolution of our galaxy over cosmic time by modeling the star formation, metallicity, cosmic-rays (CRs), outflows, and inflows of the galactic system to obtain various insights into the galactic evolution. Considering the consistencies between the observed Galactic diffuse X-ray emissions (GDXEs) and possible conditions to drive the Galactic wind by CRs, we find that the star formation rate becomes half of the mass accretion rate of the disk. The mass accretion of the disk is modeled by using the results of the dark matter N-body simulations. We find that if the gas accretion is characterized by the dark matter core radius, the rotation curve of the low-mass stars in our galaxy can be explained. These results simultaneously provide consistent amounts of metals and CRs with the current conditions of our galaxy. The most significant model predictions are that there is unidentified accretion flow with a possible number density of ∼ 0.01 /cc and the (part of) GDXEs originated from the diffuse plasma formed by consuming a roughly tenth of supernova explosion energy. The latter is the science case of future X-ray missions; XRISM, Athena, and JEDI. We also discuss further prospects of our results for the planet formation and observations of external galaxies in terms of multi-messenger astronomy. 

他、会議報告、速報など、飛び入りも歓迎します。今回もしくは次回以降、話題提供できる方は世話人までメールしていただけましたら幸いです。 

Participants: 35,  Affiliations: 16

Participants list:

Cologne PD Masato KOBAYASHI 

Ibaraki P. Munetake MOMOSE, P Toru Tsuribe

ICRR DA Jiro Shimoda

JAMSTEC PD Sota Arakawa

Kindai retired kiguchi 

Kobe 特命A Kenji Kurosaki 

Konan U. P Tsuyoshi Inoue

KyotoU B3 Kento Ishidate 

Kyushu D3 Naoto Harada, M1 Mitsuki Omura

Nagoya P Shu-ichiro Inutsuka, AP Hiroshi Kobayashi, PD Daisei Abe, D2 Kanta Kitajima, D1 Tomotaka Nishikawa, M2 Izumi Seno, M2 Fumina Kita, M1 Onogawa Kenshin, M1 Wataru Takahashi

NAOJ PD Doris Arzoumanian, PD Jeong-Gyu Kim, PD Ayaka Okuya 

RIKEN PD Ryosuke Tominaga

Shiga medical AP Motoyama 

Tohoku PD Ryunosuke Maeda, M1 Reishi Ishida

UTokyo P Yuri Aikawa, PD Shota Notsu, PD DE DIEGO German MOLPECERES, PD Anton Feeney-Johansson, PD Taiki Suzuki, D2 Kaho Morii, D2 Yoshihide Yamato, M2 Yuto Komichi, 

UTokyo-Komaba P Takeru Suzuki, PD Kensuke Kakiuchi 

次回：2023/Oct./26  17:00-

連絡世話人：冨永遼佑（理化学研究所） ryosuke.tominaga[at]riken.jp