{
  "id": "2306.02494",
  "version": "v1",
  "published": "2023-06-04T22:01:14.000Z",
  "updated": "2023-06-04T22:01:14.000Z",
  "title": "Comparative tests of accretion rates of quasars derived using a new empirical and an existing theoretical relation: Insights into black hole properties and growth",
  "authors": [
    "Yash Aggarwal"
  ],
  "comment": "17 pages, 4 figures, 1 table",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "A scaling relation based on thin-disc accretion theory has been used by some workers to determine the mass-inflow rate onto 20 high-redshift (z) and 80 Palomar-Green quasars. Based on several assumptions, it inexplicably implies that the inflow rate is an inverse function of black-hole (BH) mass Mbh. Moreover, its results remain untested. This paper offers a simple empirical relation essentially free of assumptions, found using available data for 59 highest-z quasars and the so-called Salpeter relation. We find that the accretion rate is proportional to Mbh(1+z)3, consistent with conventional astrophysics that the accretion rate is a direct function of both Mbh and the ambient gas density. We apply it to the 20 high-z and a subset of Palomar-Green quasars. Comparative analyses show that all empirically derived accretion rates and radiative efficiencies pass the tests, but their theoretical counterparts fail in most cases. A secondary relation defines the Eddington ratio as a function of z and radiative efficiency. Consistent with the empirical relations, spline regression analysis of Kozlowski's data for 132,000 quasars at z<2.4 shows that both the Eddington ratio and radiative efficiency are functions of Mbh and z. The results show that bigger BHs accrete more efficiently the smaller ones. For BHs > a billion solar masses, we get radiative efficiency of ~0.23 at z>5.7 and ~0.84 at z<0.005. Notably, the empirical relations predict a mass-inflow rate of 0.11-0,21 solar mass/year on to the BH in M87 that matches its Bondi accretion rate determined using observed density and temperature profiles.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-06-04T22:01:14.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "accretion rate",
      "black hole properties",
      "existing theoretical relation",
      "comparative tests",
      "empirical relation essentially free"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 17,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}