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
言語種別	英語
発行・発表の年月	2024/05
形態種別	学術雑誌
査読	査読あり
標題	A Self-Regulated Stochastic Acceleration Model of Pulsar Wind Nebulae
執筆形態	共同
掲載誌名	Progress of Theoretical and Experimental Physics
掲載区分	国外
出版社・発行元	Oxford University Press (OUP)
巻・号・頁	2024
著者・共著者	Shuta J Tanaka, Wataru Ishizaki
概要	<jats:title>Abstract</jats:title> <jats:p>Pulsar wind nebulae (PWNe) are clouds of magnetized relativistic electron/positron plasma supplied from the central pulsar. However, the number of radio-emitting particles inside a PWN is larger than the expectation from the study of pulsar magnetospheres and their origin is still unclear. A stochastic acceleration of externally injected particles by a turbulence inside the PWN is proposed by our previous studies. In this paper, the previous stochastic acceleration model of the PWN broadband spectra is improved by taking into account the time evolution of the turbulent energy and then the total energy balance inside a PWN is maintained. The turbulent energy supplied from the central pulsar is wasted by the backreaction from the stochastic particle acceleration and the adiabatic cooling according to the PWN expansion. The model is applied to the Crab Nebula and reproduces the current broadband emission spectrum, especially the flat radio spectrum, although the time evolution of the turbulent energy (diffusion coefficient) is a bit complicated compared with our previous studies, where we assumed an exponential behavior of the diffusion coefficient.</jats:p>
DOI	10.48550/arxiv.2405.04110
NAID	1871710641345055488