Phase-dependent Study of Near-infrared Disk Emission Lines in LB-1
Liu,Jifeng1,2,3; Zheng,Zheng4; Soria,Roberto2,5; Aceituno,Jesus6,7; Zhang,Haotong1; Lu,Youjun1,2; Wang,Song1; Hamann,Wolf-Rainer8; Oskinova,Lida M.8; Ramachandran,Varsha8; Yuan,Hailong1; Bai,Zhongrui1; Wang,Shu1; McKee,Brendan J.5; Wu,Jianfeng9; Wang,Junfeng9; Lattanzi,Mario10; Belczynski,Krzysztof11; Casares,Jorge12,13; Hernández,Jonay I. González12; Rebolo,Rafael12
Source PublicationThe Astrophysical Journal
AbstractAbstract The mass, origin, and evolutionary stage of the binary system LB-1 have been intensely debated, following the claim that it hosts an ~70M⊙ black hole, in stark contrast with the expectations for Galactic remnants. We conducted a high-resolution, phase-resolved spectroscopic study of its Paschen lines, using the Calar Alto 3.5 m telescope. We find that Paβ and Paγ (after subtraction of the stellar absorption component) are well fitted with a standard double-peaked disk profile. We measured the velocity shifts of the red and blue peaks at 28 orbital phases: the line center has an orbital motion in perfect antiphase with the secondary, and the radial velocity amplitude ranges from 8 to 13 km s?1, for different methods of profile modeling. We interpret this curve as proof that the disk traces the orbital motion of the primary, ruling out the circumbinary disk and the hierarchical triple scenarios. The phase-averaged peak-to-peak half-separation (a proxy for the projected rotational velocity of the outer part of the disk) is ~70 km s?1, larger than the orbital velocity of the secondary and inconsistent with a circumbinary disk. From those results, we infer a primary mass 4–8 times higher than the secondary mass. Moreover, we show that the intensity ratio of the blue and red peaks has a sinusoidal behavior in phase with the secondary, which we attribute to external irradiation of the outer part of the disk. Finally, we discuss our findings in the context of competing scenarios proposed for LB-1. Further astrometric Gaia data will test between alternative solutions.
KeywordBlack holes black hole physics Stellar evolution Be stars
WOS IDIOP:0004-637X-900-1-aba49e
PublisherThe American Astronomical Society
Citation statistics
Document Type期刊论文
Affiliation1.Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing, People’s Republic of China
2.School of Astronomy and Space Sciences, University of Chinese Academy of Sciences, Beijing, People’s Republic of China
3.WHU-NAOC Joint Center for Astronomy, Wuhan University, Wuhan, People’s Republic of China
4.Department of Physics and Astronomy, University of Utah, Salt Lake City, UT 84112, USA
5.Sydney Institute for Astronomy, The University of Sydney, Sydney, NSW 2006, Australia
6.Calar Alto Obsevatory, Spain
7.Instituto de Astrofsica de Andalucia, Glorieta de la Astronoma, s/n, E-18008, Granada, Spain
8.Institut für Physik und Astronomie, Universit?t Potsdam, Karl-Liebknecht-Str. 24/25, D-14476, Potsdam, Germany
9.Department of Astronomy, Xiamen University, Xiamen, People’s Republic of China
10.INAF—Osservatorio Astrofisico di Torino, Strada Osservatorio 20, I-10025 Pino Torinese TO, Italy
11.Nicolaus Copernicus Astronomical Centre, Polish Academy of Sciences, ul. Bartycka 18, PL-00-716 Warsaw, Poland
12.Instituto de Astrofísica de Canarias, c/Vía Láctea s/n, E-38200 La Laguna , Tenerife, Spain
13.Departamento de Astrofsica, Universidad de La Laguna, E-38206, Santa Cruz de Tenerife, Spain
First Author AffilicationNational Astronomical Observatories, Chinese Academy of Sciences
Recommended Citation
GB/T 7714
Liu,Jifeng,Zheng,Zheng,Soria,Roberto,et al. Phase-dependent Study of Near-infrared Disk Emission Lines in LB-1[J]. The Astrophysical Journal,2020,900(1).
APA Liu,Jifeng.,Zheng,Zheng.,Soria,Roberto.,Aceituno,Jesus.,Zhang,Haotong.,...&Rebolo,Rafael.(2020).Phase-dependent Study of Near-infrared Disk Emission Lines in LB-1.The Astrophysical Journal,900(1).
MLA Liu,Jifeng,et al."Phase-dependent Study of Near-infrared Disk Emission Lines in LB-1".The Astrophysical Journal 900.1(2020).
Files in This Item:
There are no files associated with this item.
Related Services
Recommend this item
Usage statistics
Export to Endnote
Google Scholar
Similar articles in Google Scholar
[Liu,Jifeng]'s Articles
[Zheng,Zheng]'s Articles
[Soria,Roberto]'s Articles
Baidu academic
Similar articles in Baidu academic
[Liu,Jifeng]'s Articles
[Zheng,Zheng]'s Articles
[Soria,Roberto]'s Articles
Bing Scholar
Similar articles in Bing Scholar
[Liu,Jifeng]'s Articles
[Zheng,Zheng]'s Articles
[Soria,Roberto]'s Articles
Terms of Use
No data!
Social Bookmark/Share
All comments (0)
No comment.

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