タナカ　シュウタ   TANAKA Shuta   田中　周太    所属   青山学院大学  理工学部 物理科学科    職種   助教
発行・発表の年月	2022/07
形態種別	学術雑誌
査読	査読あり
標題	X-ray line diagnostics of ion temperature at cosmic ray accelerating collisionless shocks
執筆形態	共同
掲載誌名	Publications of the Astronomical Society of Japan
掲載区分	国外
出版社・発行元	Oxford University Press (OUP)
巻・号・頁	74(5),1022-1040頁
著者・共著者	Jiro Shimoda, Yutaka Ohira, Aya Bamba, Yukikatsu Terada, Ryo Yamazaki, Tsuyoshi Inoue, Shuta J Tanaka
概要	A novel collisionless shock jump condition is suggested by modeling the entropy production at the shock transition region. We also calculate downstream developments of the atomic ionization balance and the ion temperature relaxation in supernova remnants (SNRs). The injection process and subsequent acceleration of cosmic rays (CRs) in the SNR shocks are closely related to the formation process of the collisionless shocks. Since the wave–particle interactions result in energy exchanges between electromagnetic fields and charged particles, the randomization of particles associated with the shock transition may occur at a rate given by the scalar product of the electric field and current. We find that order-of-magnitude estimates of the randomization with reasonable strength of the electromagnetic fields in the SNR constrain the amount of CR nuclei and the ion temperatures. The constrained amount of CR nuclei can be sufficient to explain the Galactic CRs.
DOI	10.1093/pasj/psac053
ISSN	00046264
NAID	1360580232384712576