{
  "id": "2109.10321",
  "version": "v1",
  "published": "2021-09-21T17:16:02.000Z",
  "updated": "2021-09-21T17:16:02.000Z",
  "title": "Detectability of Population III stellar remnants as X-ray binaries from tidal captures in the local Universe",
  "authors": [
    "Rabia Husain",
    "Boyuan Liu",
    "Volker Bromm"
  ],
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "We assess the feasibility of detecting the compact object remnants from Population III (Pop III) stars in nearby dense star clusters, where they become luminous again as X-ray binaries (XRBs) and tidal disruption events (TDEs) via strong tidal encounters. Analytically modelling the formation of Pop III stars, coupled with a top-heavy initial mass function predicted by numerical simulations, we derive the number of (active) Pop III XRBs and TDEs in the present-day Milky Way (MW) nuclear star cluster as $\\sim 0.06-0.3$ and $\\lesssim 4\\times 10^{-6}$, rendering any detection unlikely. The detection probability, however, can be significantly boosted when surveying all massive star clusters from the MW and neighboring galaxy clusters. Specifically, we predict $\\sim 1.5-6.5$ and $\\sim 40-2800$ active Pop III XRBs in the MW and the Virgo cluster, respectively. Our Pop III XRBs are dominated ($\\sim 99\\%$) by black holes with a typical mass and luminosity of $\\sim 45$ $\\rm M_{\\odot}$ and $\\sim 10^{36}$ $\\rm erg\\ s^{-1}$. Deep surveys of nearby ($\\lesssim 30-300$ $\\rm Mpc$) galaxy clusters for such Pop III XRBs are well within reach of next-generation X-ray telescopes, such as ATHENA and LYNX.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2021-09-21T17:16:02.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "x-ray binaries",
      "stellar remnants",
      "local universe",
      "tidal captures",
      "population"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}