中国科学院机构知识库网格
Chinese Academy of Sciences Institutional Repositories Grid
Plausibility of ultraviolet burst generation in the low solar chromosphere

文献类型:期刊论文

作者Ni L(倪蕾)1,2,3,4; Cheng GC(程冠冲)1,4; Lin J(林隽)1,2,4
刊名ASTRONOMY & ASTROPHYSICS
出版日期2022-09-16
卷号665
ISSN号0004-6361
关键词magnetohydrodynamics (MHD) magnetic reconnection Sun: chromosphere Sun: UV radiation methods: numerical radiation mechanisms: thermal
DOI10.1051/0004-6361/202243304
产权排序第1完成单位
文献子类Article
英文摘要

Context. Ultraviolet (UV) bursts and Ellerman bombs (EBs) are small-scale magnetic reconnection events taking place in the highly stratified, low solar atmosphere. The plasma density, reconnection mechanisms, radiative cooling and transfer processes clearly differ from one layer of the atmosphere to the next. In particular, EBs are believed to form in the upper photosphere or the low chromosphere. It is still not clear whether UV bursts have to be generated at a higher atmospheric layer than the EBs or whether both UV bursts and EBs can occur in the low chromosphere. Aims. We numerically studied the low beta magnetic reconnection process around the solar temperature minimum region (TMR) by including more realistic physical diffusions and radiative cooling models. We aim to find out whether UV bursts may occur in the low chromosphere and to investigate the dominant mechanism that accounts for heating in the UV burst in the chromosphere. Methods. We used the single-fluid magnetohydrodynamic (MHD) code NIRVANA to perform the simulations. The time-dependent ionization degrees of hydrogen and helium are included in the code, which lead to a more realistic magnetic diffusion caused by electron-neutral collision and ambipolar diffusion. A more realistic radiative cooling model is also included in the simulations. The initial mass density and temperature are 1.66057 x 10(-6 )kg m(-)(3) and 4400 K, respectively, values that are typical for the plasma environment around TMR. Results. Our results in high resolution indicate that the plasmas in the reconnection region are heated up to more than 20 000 K if the reconnecting magnetic field is as strong as 500 G, which suggests that UV bursts can be generated in the dense low chromosphere. The dominant mechanism for producing the UV burst in the low chromosphere is heating, as a result of the local compression in the reconnection process. The thermal energy occurring in the reconnection region rapidly increases after the turbulent reconnection mediated by plasmoids is invoked. The average power density of the generated thermal energy in the reconnection region can reach over 1000 erg cm(-3) s(-1), which is comparable to the average power density accounting for a UV burst. With the strength of the reconnecting magnetic field exceeding 900 G, the width of the synthesized Si IV 1394 angstrom line profile with multiple peaks can reach up to 100 km s(-1), which is consistent with observations.

学科主题天文学 ; 太阳与太阳系 ; 太阳物理学
URL标识查看原文
出版地17, AVE DU HOGGAR, PA COURTABOEUF, BP 112, F-91944 LES ULIS CEDEX A, FRANCE
WOS关键词STRONGLY MAGNETIZED REGIONS ; TRANSPORT-COEFFICIENTS ; FLUX EMERGENCE ; ELLERMAN BOMBS ; RECONNECTION ; MODELS ; FLARE
资助项目NSFC[11973083] ; NSFC[11933009] ; Strategic Priority Research Program of CAS[XDA17040507] ; Youth Innovation Promotion Association CAS[Y2021024] ; Applied Basic Research of Yunnan Province in China[2018FB009] ; CAS Key Laboratory of Solar activity[KLSA202103] ; Yunling Talent Project for the Youth ; Yunling Scholar Project of the Yunnan Province ; Yunnan Key Laboratory of Solar Physics and Space Science[202205AG070009] ; Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (second phase)[nsfc2015-460] ; Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (second phase)[nsfc2015-463] ; Yunnan Province Scientist Workshop of Solar Physics ; project of the Group for Innovation of Yunnan Province[2018HC023]
WOS研究方向Astronomy & Astrophysics
语种英语
出版者EDP SCIENCES S A
WOS记录号WOS:000854291300005
资助机构NSFC[11973083, 11933009] ; Strategic Priority Research Program of CAS[XDA17040507] ; Youth Innovation Promotion Association CAS[Y2021024] ; Applied Basic Research of Yunnan Province in China[2018FB009] ; CAS Key Laboratory of Solar activity[KLSA202103] ; Yunling Talent Project for the Youth ; Yunling Scholar Project of the Yunnan Province ; Yunnan Key Laboratory of Solar Physics and Space Science[202205AG070009] ; Special Program for Applied Research on Super Computation of the NSFC-Guangdong Joint Fund (second phase)[nsfc2015-460, nsfc2015-463] ; Yunnan Province Scientist Workshop of Solar Physics ; project of the Group for Innovation of Yunnan Province[2018HC023]
版本出版稿
源URL[http://ir.ynao.ac.cn/handle/114a53/25574]  
专题云南天文台_太阳物理研究组
通讯作者Ni L(倪蕾)
作者单位1.University of Chinese Academy of Sciences, Beijing 100049, PR China
2.Center for Astronomical Mega-Science, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing 100012, PR China;
3.Key Laboratory of Solar Activity, National Astronomical of Observatories, Chinese Academy of Sciences, Beijing 100012, PR China;
4.Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan 650216, PR China;
推荐引用方式
GB/T 7714
Ni L,Cheng GC,Lin J. Plausibility of ultraviolet burst generation in the low solar chromosphere[J]. ASTRONOMY & ASTROPHYSICS,2022,665.
APA Ni L,Cheng GC,&Lin J.(2022).Plausibility of ultraviolet burst generation in the low solar chromosphere.ASTRONOMY & ASTROPHYSICS,665.
MLA Ni L,et al."Plausibility of ultraviolet burst generation in the low solar chromosphere".ASTRONOMY & ASTROPHYSICS 665(2022).

入库方式: OAI收割

来源:云南天文台

浏览0
下载0
收藏0
其他版本

除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。