YNAO OpenIR  > 中国科学院天体结构与演化重点实验室
临界转动恒星Achernar的斜压结构与引力昏暗的精细研究
Alternative TitleDetail investigation of the inclined pressure structure and gravity darkening in critical rotating star Achernar
邰丽婷1; 宋汉峰1,2,3; 王江涛1
Source Publication物理学报(ACTA PHYSICA SINICA)
2016-02-20
Volume65Issue:4
DOI10.7498/aps.65.049701
Indexed BySCI ; EI ; CSCD ; 核心
Keyword转动 潮汐 斜压结构 引力昏暗
Abstract

转动和潮汐效应是影响恒星结构和演化的非常重要的物理因素. 根据对Achernar的观测数据, 用扰动理论推导了临界转动恒星Achernar分别作为单星和双星的斜压结构的特征, 给出Achernar等压面上的密度等物理量的分布. 利用考虑转动和潮汐及形变效应的单、双星模型研究了Achernar的引力昏暗现象. 结果表明正剪切增强离心力、减小赤道的重力加速度和温度, 反剪切结果则与之相反. 反剪切和刚性转动情况并不符合对Achernar的引力昏暗观测结果. 发现转动双星模型比单星模型虽更符合Achernar赤道和极半径之比的观测值, 但理论计算的角速度比观测值小. 对比理论计算和观测结果发现, 当Achernar的自转角速度为4.65× 10-5 s-1, 正剪切率Ω/Ωs为0.7851时, Achernar的极点温度为16041 K, 赤道温度为12073 K. 所有理论计算与观测值的相对误差不超过7%.

Other Abstract

Rotation and tide are two important factors that have very important impacts on the stellar structure and evolution. Based on the observational data ofAchernar, we have derived the inclined pressure structure in a single rotating star or as a member in the binaries. We have given the distributions of thephysical quantities on the isobaric surface and these distributions are derived from the Legendre series of expansions. We have also found the relationship between all levels of perturbation potential functions (including rotational and tidal distortions) and the distributions of density and pressure under thecondition of inclined pressure structure. In particular, the gravitational darkening with the models including the effects of rotation and tide is investigated. We have found that the critical ratio of equatorial radius to the polar radius is consistent with the observations in rotating binaries better than that in single rotating model. The reason is that the tidal force can make the polar radius shortened because the tidal force exerts an inward force to the two polar points. However, the theoretical angular velocity in binaries is smaller than that observed. It is also shown that the positive shear enhances the centrifugal force and decreases the mean effective gravitational acceleration and effective temperatures whereas the negative shear plays a role to strengthen the effective gravitational acceleration. Moreover, the solid body rotation has not been supported inside Achernar because magnetic fields have not been detected through observations. Furthermore, the theoretical angular velocity in rigid rotation is higher than the angular velocity observed. Achernar has a periodic variation of light curves due to mass outburst, which also supports differential rotation. A positive shear indicates that the mass in accretion disks is falling to Achernar and the Achernar is spun up to critical rotation according to current observations. By comparing the theoretical results with observations, it can be seen that when the theoretical spin angular velocity of Achernar is 4.65 x 10(-5) s(-1) and the positive shears Omega/Omega(s) are 0.7851, the temperature ofthe polar points is 16041 K and that of equatorial sphere is 12073 K. Relative errors between the theoretical values and observations are less than 3% and are listed in the text. This model is the best and is the most possible one for Achernar.

Funding Project国家自然科学基金[11463002] ; 中国科学院天体结构与演化重点实验室开放课题[OP201405] ; 贵州大学研究生创新基金[研理工2015055]
Funding Organization国家自然科学基金[11463002] ; 中国科学院天体结构与演化重点实验室开放课题[OP201405] ; 贵州大学研究生创新基金[研理工2015055]
Language中文
Subject Area物理学 ; 天文学 ; 恒星与银河系 ; 恒星物理学
MOST Discipline Catalogue理学 ; 理学::天文学
SubtypeArticle
PublisherCHINESE PHYSICAL SOC
Publication PlaceP O BOX 603, BEIJING 100080, PEOPLES R CHINA
ISSN1000-3290
URL查看原文
WOS IDWOS:000371401000045
WOS Research AreaPhysics
WOS SubjectPhysics, Multidisciplinary
WOS KeywordEVOLUTIONARY MODELS ; STELLAR EVOLUTION ; ANGULAR-MOMENTUM ; LOW-MASS ; THEOREM
CSCD IDCSCD:5650865
EI Accession Number20161102092068
EI KeywordsShear flow
EI Classification Number471.4Seawater, Tides and Waves - 631.1Fluid Flow, General - 657.2Extraterrestrial Physics and Stellar Phenomena - 701.1Electricity: Basic Concepts and Phenomena - 931.1Mechanics
Citation statistics
Cited Times:2[CSCD]   [CSCD Record]
Document Type期刊论文
Identifierhttp://ir.ynao.ac.cn/handle/114a53/9347
Collection中国科学院天体结构与演化重点实验室
Corresponding Author宋汉峰
Affiliation1.贵州大学理学院物理系, 贵阳, 550025
2.中国科学院天体结构与演化重点实验室, 昆明, 650011
3.中国科学院国家天文台-贵州大学天文联合研究中心, 贵阳, 550025
Recommended Citation
GB/T 7714
邰丽婷,宋汉峰,王江涛. 临界转动恒星Achernar的斜压结构与引力昏暗的精细研究[J]. 物理学报(ACTA PHYSICA SINICA),2016,65(4).
APA 邰丽婷,宋汉峰,&王江涛.(2016).临界转动恒星Achernar的斜压结构与引力昏暗的精细研究.物理学报(ACTA PHYSICA SINICA),65(4).
MLA 邰丽婷,et al."临界转动恒星Achernar的斜压结构与引力昏暗的精细研究".物理学报(ACTA PHYSICA SINICA) 65.4(2016).
Files in This Item:
File Name/Size DocType Version Access License
临界转动恒星Achernar的斜压结构与(616KB)期刊论文出版稿开放获取CC BY-NC-SAView Application Full Text
Related Services
Recommend this item
Bookmark
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[邰丽婷]'s Articles
[宋汉峰]'s Articles
[王江涛]'s Articles
Baidu academic
Similar articles in Baidu academic
[邰丽婷]'s Articles
[宋汉峰]'s Articles
[王江涛]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[邰丽婷]'s Articles
[宋汉峰]'s Articles
[王江涛]'s Articles
Terms of Use
No data!
Social Bookmark/Share
File name: 临界转动恒星Achernar的斜压结构与引力昏暗的精细研究.pdf
Format: Adobe PDF
All comments (0)
No comment.
 

Items in the repository are protected by copyright, with all rights reserved, unless otherwise indicated.