{
  "id": "2205.11734",
  "version": "v1",
  "published": "2022-05-24T03:00:47.000Z",
  "updated": "2022-05-24T03:00:47.000Z",
  "title": "Mass-Ratio Distribution of Binaries From the LAMOST-MRS Survey",
  "authors": [
    "Jiangdan Li",
    "Jiao Li",
    "Chao Liu",
    "Chunqian Li",
    "Yanjun Guo",
    "Luqian Wang",
    "Xuefei Chen",
    "Lifeng Xing",
    "Yonghui Hou",
    "Zhanwen Han"
  ],
  "comment": "18 pages, 12 figures, accepted for publication in The Astrophysical Journal",
  "categories": [
    "astro-ph.SR",
    "astro-ph.GA"
  ],
  "abstract": "Binary evolution leads to the formation of important objects crucial to the development of astrophysics, but the statistical properties of binary populations are still poorly understood. The LAMOST-MRS has provided a large sample of stars to study the properties of binary populations, especially for the mass ratio distributions and the binary fractions. We have devised a Peak Amplitude Ratio (PAR) approach to derive the mass ratio of a binary system based on results obtained from its spectrum. By computing a cross-correlation function (CCF), we established a relationship between the derived mass ratio and the PARs of the binary systems. By utilizing spectral observations obtained from LAMSOT DR6 & DR7, we applied the PAR approach to form distributions of the derived mass ratio of the binary systems to the spectral types. We selected the mass ratio within the range of $0.6-1.0$ for investigating the mass-ratio distribution. Through a power-law fitting, we obtained the power index $\\gamma$ values of $-0.42\\pm0.27$, $0.03\\pm0.12$, and $2.12\\pm0.19$ for A-, F-, and G-type stars identified in the sample, respectively. The derived $\\gamma$-values display an increasing trend toward lower primary star masses, and G-type binaries tend to be more in twins. The close binary fractions (for $P\\lesssim 150\\,{\\rm d}$ and $q\\gtrsim 0.6$) in our sample for A, F and G binaries are $7.6\\pm 0.5 \\%$, $4.9\\pm 0.2 \\%$ and $3.7 \\pm 0.1 \\%$, respectively. Note that the PAR approach can be applied to large spectroscopic surveys of stars.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-05-24T03:00:47.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "mass-ratio distribution",
      "lamost-mrs survey",
      "binary system",
      "derived mass ratio",
      "par approach"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 18,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}