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arXiv · 1902.02813

A Method to Search for Black Hole Candidates with Giant Companions by LAMOST

Wei-Min Gu·Hui-Jun Mu·Jin-Bo Fu·Ling-Lin Zheng·Tuan Yi·Zhong-Rui Bai·Song Wang·Hao-Tong Zhang·Ya-Juan Lei·Yu Bai·Jianfeng Wu·Junfeng Wang·Jifeng Liu
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Abstract

We propose a method to search for stellar-mass black hole (BH) candidates with giant companions from spectroscopic observations. Based on the stellar spectra of LAMOST Data Release 6, we obtain a sample of seven giants in binaries with large radial velocity variation $\Delta V_R > 80~{\rm km~s^{-1}}$. With the effective temperature, surface gravity, and metallicity provided by LAMOST, and the parallax given by {\it Gaia}, we can estimate the mass and radius of the giant, and therefore evaluate the possible mass of the optically invisible star in the binary. We show that the sources in our sample are potential BH candidates, and are worthy of dynamical measurement by further spectroscopic observations. Our method may be particularly valid for the selection of BH candidates in binaries with unknown orbital periods.

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Wei-Min Gu, Hui-Jun Mu, Jin-Bo Fu, Ling-Lin Zheng, Tuan Yi, Zhong-Rui Bai, Song Wang, Hao-Tong Zhang, Ya-Juan Lei, Yu Bai, Jianfeng Wu, Junfeng Wang, Jifeng Liu. 2019-02-07. A Method to Search for Black Hole Candidates with Giant Companions by LAMOST. https://doi.org/10.3847/2041-8213/ab04f0

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