{
  "$schema": "./item.schema.json",
  "id": "maximum-discs",
  "type": "publication",
  "cvs": [
    "np"
  ],
  "date": {
    "start": "2018-02"
  },
  "title": "A new algorithm to quantify maximum discs in galaxies",
  "shortTitle": "Quantifying Maximum Discs",
  "nickTitle": "Maximum Discs",
  "status": "published",
  "entryType": "article",
  "authors": [
    {
      "family": "Starkman",
      "given": "Nathaniel",
      "me": true,
      "orcid": "0000-0003-3954-3291"
    },
    {
      "family": "Lelli",
      "given": "F.",
      "orcid": "0000-0002-9024-9883",
      "affiliation": "European Southern Observatory, Karl-Schwarzschield-Strasse 2, D-85748 Garching bei, München, Germany"
    },
    {
      "family": "McGaugh",
      "given": "S. S.",
      "orcid": "0000-0002-9762-0980",
      "affiliation": "Departments of Physics and Astronomy, Case Western Reserve University, Euclid Ave, Cleveland, 4410 OH, USA"
    },
    {
      "family": "Schombert",
      "given": "J.",
      "orcid": "0000-0003-2022-1911",
      "affiliation": "Department of Physics, University of Oregon, Willamette Hall, Eugene, 9740 OR, USA"
    }
  ],
  "venue": {
    "journal": "Monthly Notices of the Royal Astronomical Society",
    "volume": "480",
    "pages": "2292"
  },
  "arxiv": "1802.09967",
  "primaryClass": "astro-ph.GA",
  "bibcode": "2018MNRAS.480.2292S",
  "doi": "10.1093/mnras/sty2011",
  "links": [
    {
      "rel": "paper",
      "url": "https://academic.oup.com/mnras/article/480/2/2292/5060779"
    }
  ],
  "tags": [
    "dark-matter",
    "extragalactic",
    "dynamics"
  ],
  "citekey": "Starkman+:2018:maximum-discs",
  "abstract": "Maximum disc decompositions of rotation curves place a dynamical upper limit to the mass attributable to stars in galaxies. The precise definition of this term, however, can be vague and varies in usage. We develop an algorithm to robustly quantify maximum-disc mass models and apply it to 153 galaxies from the SPARC database. Our automatic procedure recovers classic results from manual decompositions. High-mass, high-surface-brightness galaxies have mean maximum-disc mass-to-light ratios of $\\sim 0.7\\;{\\rm M}_\\odot/{\\rm L}_\\odot$ in the Spitzer 3.6 μm band, which are close to the expectations from stellar population models, suggesting that these galaxies are nearly maximal. Low-mass, low-surface-brightness galaxies have very high maximum-disc mass-to-light ratios (up to 10 ${\\rm M}_\\odot/{\\rm L}_\\odot$), which are unphysical for standard stellar population models, confirming they are sub-maximal. The maximum-disc mass-to-light ratios are more closely correlated with surface brightness than luminosity. The mean ratio between baryonic and observed velocity at the peak of the baryonic contribution is $V_{\\rm bar}/V_{\\rm p} \\approx 0.88$, but correlates with surface brightness, so it is unwise to use this mean value to define the maximum disc concept. Our algorithm requires no manual intervention and could be applied to large galaxy samples from future HI surveys with Apertif, Askap, and SKA.",
  "highlight": {
    "topic": "extragalactic",
    "image": "highlights/maximum-discs.webp",
    "alt": "Rotation curve of the low-surface-brightness galaxy UGC 128: the observed speeds as points with error bars, the gas contribution, and the stellar disc and total baryonic contributions at both the stellar-population mass-to-light ratio and the maximum-disc value. Making its disc maximal needs a far heavier disc than its stars imply.",
    "description": "A galaxy’s rotation comes from both its stars and its dark matter. A “maximum disc” gives the stars as much of that rotation as possible, but the term was never precisely defined. A new algorithm measures it across 153 SPARC galaxies: bright galaxies come close to a maximum disc, while faint ones cannot — their stars would have to be unrealistically heavy for their light."
  }
}