{
  "id": "2310.11496",
  "version": "v1",
  "published": "2023-10-17T18:00:05.000Z",
  "updated": "2023-10-17T18:00:05.000Z",
  "title": "The Peak of the Fallback Rate from Tidal Disruption Events: Dependence on Stellar Type",
  "authors": [
    "Ananya Bandopadhyay",
    "Julia Fancher",
    "Aluel Athian",
    "Valentino Indelicato",
    "Sarah Kapalanga",
    "Angela Kumah",
    "Daniel A. Paradiso",
    "Matthew Todd",
    "Eric R. Coughlin",
    "C. J. Nixon"
  ],
  "comment": "10 pages, 4 figures, ApJL accepted",
  "categories": [
    "astro-ph.HE",
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "A star completely destroyed in a tidal disruption event (TDE) ignites a luminous flare that is powered by the fallback of tidally stripped debris to a supermassive black hole (SMBH) of mass $M_{\\bullet}$. We analyze two estimates for the peak fallback rate in a TDE, one being the \"frozen-in\" model, which predicts a strong dependence of the time to peak fallback rate, $t_{\\rm peak}$, on both stellar mass and age, with $15\\textrm{ days} \\lesssim t_{\\rm peak} \\lesssim 10$ yr for main sequence stars with masses $0.2\\le M_{\\star}/M_{\\odot} \\le 5$ and $M_{\\bullet} = 10^6M_{\\odot}$. The second estimate, which postulates that the star is completely destroyed when tides dominate the maximum stellar self-gravity, predicts that $t_{\\rm peak}$ is very weakly dependent on stellar type, with $t_{\\rm peak} = \\left(23.2\\pm4.0\\textrm{ days}\\right)\\left(M_{\\bullet}/10^6M_{\\odot}\\right)^{1/2}$ for $0.2\\le M_{\\star}/M_{\\odot} \\le 5$, while $t_{\\rm peak} = \\left(29.8\\pm3.6\\textrm{ days}\\right)\\left(M_{\\bullet}/10^6M_{\\odot}\\right)^{1/2}$ for a Kroupa initial mass function truncated at $1.5 M_{\\odot}$. This second estimate also agrees closely with hydrodynamical simulations, while the frozen-in model is discrepant by orders of magnitude. We conclude that (1) the time to peak luminosity in complete TDEs is almost exclusively determined by SMBH mass, and (2) massive-star TDEs power the largest accretion luminosities. Consequently, (a) decades-long extra-galactic outbursts cannot be powered by complete TDEs, including massive-star disruptions, and (b) the most highly super-Eddington TDEs are powered by the complete disruption of massive stars, which -- if responsible for producing jetted TDEs -- would explain the rarity of jetted TDEs and their preference for young and star-forming host galaxies.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-10-17T18:00:05.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "tidal disruption event",
      "stellar type",
      "peak fallback rate",
      "dependence",
      "complete tdes"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 10,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}