{
  "id": "2309.11548",
  "version": "v1",
  "published": "2023-09-20T18:00:02.000Z",
  "updated": "2023-09-20T18:00:02.000Z",
  "title": "Studying [CII] Emission in Low-mass Galaxies at z ~ 7",
  "authors": [
    "Kelsey Glazer",
    "Marusa Bradac",
    "Ryan L. Sanders",
    "Seiji Fujimoto",
    "Patricia Bolan",
    "Andrea Ferrara",
    "Victoria Strait",
    "Tucker Jones",
    "Brian C. Lemaux",
    "Livia Vallini",
    "Russell Ryan"
  ],
  "comment": "7 pages, 4 figures submitted to MNRAS",
  "categories": [
    "astro-ph.GA",
    "astro-ph.CO"
  ],
  "abstract": "We report on a $\\rm{[CII]}_{158\\mu\\rm{m}}$ search using the Atacama Large Millimeter/submillimeter Array (ALMA) on three lensed, confirmed {\\lya} emitting galaxies at $z \\sim 7$. Our targets are ultra-violet (UV) faint systems with stellar masses on the order of $M_{*} \\sim 10^{9} M_{\\odot}$. We detect a single [CII] line emission ($4\\sigma$) from the brightest ($L \\sim 2.4 \\times 10^{10}L_{\\odot}$) galaxy in our sample, MACS0454-1251. We determine a systemic redshift ($z_{\\rm{[CII]}} = 6.3151 \\pm 0.0005$) for MACS0454-1251 and measure a {\\lya} velocity offset of $\\Delta v \\approx 300 \\pm 70 \\rm{km\\,s}^{-1}$. The remaining two galaxies we detect no {\\ct} but provide $3 \\sigma$ upper limits on their {\\ct} line luminosities which we use to investigate the $L_{\\textrm{[CII]}} - \\rm{SFR}$ relation. Overall our single {\\ct} detection shows agreement with the relation for dwarf and local starburst galaxies. Our [CII] deficient galaxies could potentially be exhibiting low metallicities ($Z<Z_{\\odot}$). Another possible explanation for weaker [CII] emission could be strong feedback from star formation disrupting molecular clouds. We do not detect continuum emission in any of the sources, placing upper limits on their dust masses. Assuming a single dust temperature of $T_{d}=35 \\rm{K}$ dust masses ($M_{\\rm{dust}}$) range from $< 4.8 \\times 10^{7} M_{\\odot} $ to $2.3 \\times 10^{8} M_{\\odot}$. Collectively, our results suggest faint reionization era sources could be metal poor and/or could have strong feedback suppressing [CII] emission.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-09-20T18:00:02.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "low-mass galaxies",
      "dust masses",
      "upper limits",
      "faint reionization era sources",
      "atacama large millimeter/submillimeter array"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 7,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}