Red Asymmetry of H α Line Profiles during the Flares on the Active RS CVn-type Star II Pegasi

doi:10.3847/1538-4357/ad1928

	Red Asymmetry of H α Line Profiles during the Flares on the Active RS CVn-type Star II Pegasi
	Cao DT(曹东涛)2,3,4; Gu SH(顾盛宏)1,2,4
刊名	ASTROPHYSICAL JOURNAL
	2024-03-01
卷号	963 期号:1
ISSN号	0004-637X
DOI	10.3847/1538-4357/ad1928
产权排序	第1完成单位
文献子类	Article
英文摘要	Stellar coronal mass ejections (CMEs) have recently attracted much attention for their impacts on stellar evolution and surrounding exoplanets. RS CVn-type stars could produce large flares, and therefore may have frequent CMEs. Here we report the capture of a possible CME or chromospheric condensation on the RS CVn-type star II Pegasi (II Peg) using high-resolution spectroscopic observation. Two flares were detected during the observation, and the low limits of the flare energies are of the order of 10(33) erg and 10(34 )erg, respectively. Using mean spectrum subtraction, the H (alpha) residual shows red asymmetry during the flares, and the redshifted broad emission components are probably caused by chromospheric condensation or coronal rain. Moreover, a far redshifted extra emission component with a high bulk velocity of 429 km s(-1) was observed during the second flare and is probably due to a prominence eruption. The velocity greatly exceeds the star's escape velocity, which means that this eruption can develop into a CME. The CME mass is estimated to be 0.83-1.48 x 10(20) g, which is slightly larger than the value expected from solar flare-CME extrapolation. The kinetic energy of CME, derived to be 0.76-1.15 x 10(35) erg, is less than the kinetic energy extrapolated from solar events. Additionally, we could not completely rule out the possibility of chromospheric condensation resulting in the far redshifted extra emission. Finally, there is a blueshifted broad component in the subtracted H (alpha )profile derived using synthesized spectral subtraction when no flare happened, and its behavior is associated with the H- alpha activity features.
学科主题	天文学
URL标识	查看原文
出版地	TEMPLE CIRCUS, TEMPLE WAY, BRISTOL BS1 6BE, ENGLAND
资助项目	National Natural Science Foundation of China (NSFC)https://doi.org/10.13039/501100001809; Open Project Program of the Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences[10373023]; Open Project Program of the Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences[10773027]; Open Project Program of the Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences[11333006]; Open Project Program of the Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences[U1531121]; National Natural Science Foundation of China (NSFC)[202201AT070186]; National Natural Science Foundation of China (NSFC)[202305AS350009]; Yunnan Fundamental Research Projects; Yunnan Revitalization Talent Support Program (Young Talent Project)[202302AN360001]; International Centre of Supernovae, Yunnan Key Laboratory; China Manned Space Project
WOS关键词	CORONAL MASS EJECTIONS ; MULTIWAVELENGTH OPTICAL OBSERVATIONS ; MAIN-SEQUENCE STARS ; YZ CANIS MINORIS ; X-RAY EMISSION ; 2 M-DWARFS ; CANUM-VENATICORUM ; ROTATIONAL MODULATION ; BINARY-SYSTEMS ; CHROMOSPHERIC ACTIVITY
WOS研究方向	Astronomy & Astrophysics
语种	英语
出版者	IOP Publishing Ltd
WOS记录号	WOS:001174541700001
资助机构	National Natural Science Foundation of China (NSFC)https://doi.org/10.13039/501100001809 ; Open Project Program of the Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences[10373023, 10773027, 11333006, U1531121] ; National Natural Science Foundation of China (NSFC)[202201AT070186, 202305AS350009] ; Yunnan Fundamental Research Projects ; Yunnan Revitalization Talent Support Program (Young Talent Project)[202302AN360001] ; International Centre of Supernovae, Yunnan Key Laboratory ; China Manned Space Project
内容类型	期刊论文
版本	出版稿
源URL	[http://ir.ynao.ac.cn/handle/114a53/26468]
专题	云南天文台_系外行星研究组
作者单位	1.School of Astronomy and Space Science, University of Chinese Academy of Sciences, Beijing 101408, People's Republic of China 2.Yunnan Observatories, Chinese Academy of Sciences, Kunming 650216, People's Republic of China; dtcao@ynao.ac.cn, shenghonggu@ynao.ac.cn; 3.International Centre of Supernovae, Yunnan Key Laboratory, Kunming 650216, People's Republic of China; 4.Key Laboratory for the Structure and Evolution of Celestial Objects, Chinese Academy of Sciences, Kunming 650216, People's Republic of China;
推荐引用方式 GB/T 7714	Cao DT,Gu SH. Red Asymmetry of H α Line Profiles during the Flares on the Active RS CVn-type Star II Pegasi[J]. ASTROPHYSICAL JOURNAL,2024,963(1).
APA	曹东涛,&顾盛宏.(2024).Red Asymmetry of H α Line Profiles during the Flares on the Active RS CVn-type Star II Pegasi.ASTROPHYSICAL JOURNAL,963(1).
MLA	曹东涛,et al."Red Asymmetry of H α Line Profiles during the Flares on the Active RS CVn-type Star II Pegasi".ASTROPHYSICAL JOURNAL 963.1(2024).