{
  "id": "2312.12378",
  "version": "v1",
  "published": "2023-12-02T15:33:12.000Z",
  "updated": "2023-12-02T15:33:12.000Z",
  "title": "A Statistical Study of Soft X-ray Flares on Solar-type Stars",
  "authors": [
    "Zhanhao Zhao",
    "Ziqian Hua",
    "Xin Cheng",
    "Zhiyuan Li",
    "Mingde Ding"
  ],
  "categories": [
    "astro-ph.SR",
    "astro-ph.HE"
  ],
  "abstract": "The statistical characteristic of stellar flares at optical bands has received an extensive study, but it remains to be studied at soft X-ray bands, in particular for solar-type stars. Here, we present a statistical study of soft X-ray flares on solar-type stars, which can help understand multi-wavelength behaviors of stellar flares. We mainly use Chandra Source Catalog Release 2.0, which includes a number of flaring stars with denoted variability, and Gaia Data Release 3, which includes necessary information for classifying stars. We also develop a set of methods for identifying and classifying stellar soft X-ray flares and estimating their properties. A detailed statistical investigation for 129 flare samples on 103 nearby solar-type stars as selected yields the following main results. (1) The flare energy emitted at the soft X-ray band in our sample ranges from $\\sim 10^{33}$ to $\\sim 10^{37} \\ \\mathrm{erg}$, and the majority of them are superflares with the most energetic one having energy of $6.0_{-4.7}^{+3.2} \\times 10^{37} \\ \\mathrm{erg}$. (2) The flare duration is related to its energy as formulated by $T_\\mathrm{duration,SXR} \\propto E_\\mathrm{flare,SXR}^{\\ 0.201 \\pm 0.024}$, which is different from those derived at optical and NIR bands, indicating distinct radiation mechanisms at different bands. (3) The frequency distribution of stellar flares as a function of energy is formulated as $\\mathrm{d} N_\\mathrm{flare} / \\mathrm{d} E_\\mathrm{flare,SXR} \\propto E_\\mathrm{flare,SXR}^{\\ -1.77}$, which is similar to the results found at other bands and on other types of stars, indicating that the energy emitted at the soft X-ray band could be a constant fraction of the full-band bolometric energy.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-12-02T15:33:12.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "solar-type stars",
      "statistical study",
      "soft x-ray band",
      "stellar flares",
      "help understand multi-wavelength behaviors"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}