{
  "id": "1507.04515",
  "version": "v1",
  "published": "2015-07-16T10:19:54.000Z",
  "updated": "2015-07-16T10:19:54.000Z",
  "title": "Angular momentum of disc galaxies with a lognormal density distribution",
  "authors": [
    "John Herbert Marr"
  ],
  "comment": "Submitted to MNRAS June 2015",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "Whilst most galaxy properties scale with galaxy mass, similar scaling relations for angular momentum are harder to demonstrate. A lognormal (LN) density distribution for disc mass provides a good overall fit to the observational data for disc rotation curves for a wide variety of galaxy types and luminosities. In this paper, the total angular momentum J and energy $\\vert{}$E$\\vert{}$ were computed for 38 disc galaxies from the published rotation curves and plotted against the derived disc masses, with best fit slopes of 1.683$\\pm{}$0.018 and 1.643$\\pm{}$0.038 respectively, using a theoretical model with a LN density profile. The derived mean disc spin parameter was $\\lambda{}$=0.423$\\pm{}$0.014. Using the rotation curve parameters V$_{max}$ and R$_{max}$ as surrogates for the virial velocity and radius, the virial mass estimator $M_{disc}\\propto{}R_{max}V_{max}^2$ was also generated, with a log-log slope of 1.024$\\pm{}$0.014 for the 38 galaxies, and a proportionality constant ${\\lambda{}}^*=1.47\\pm{}0.20\\times{}{10}^5\\ M_{sun\\ }{kpc}^{-1}{km}^{-2}\\ s^2$. This relationship was close to the theoretical slope of 1, and had less scatter than the corresponding Tully Fisher relation, $M\\propto{}{\\left(V_{rot}\\right)}^{\\alpha{}}$, suggesting that the virial mass estimator may provide an alternative method to determine disc masses.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2015-07-16T10:19:54.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "angular momentum",
      "lognormal density distribution",
      "disc galaxies",
      "disc mass",
      "rotation curve"
    ],
    "publication": {
      "doi": "10.1093/mnras/stv1734"
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1383202
    }
  }
}