{
  "id": "2212.09543",
  "version": "v1",
  "published": "2022-12-19T15:35:50.000Z",
  "updated": "2022-12-19T15:35:50.000Z",
  "title": "First detection of CHD$_{2}$OH towards pre-stellar cores",
  "authors": [
    "Yuxin Lin",
    "Silvia Spezzano",
    "Paola Caselli"
  ],
  "comment": "accepted by A&A letter",
  "categories": [
    "astro-ph.GA",
    "astro-ph.SR"
  ],
  "abstract": "The inheritance of material across the star and planet formation process is traced by deuterium fractionation. We report here the first detection of doubly deuterated methanol towards pre-stellar cores. We study the deuterium fractionation of methanol, CH$_{3}$OH, towards two starless and two pre-stellar cores. We derive a D/H ratio of 0.8-1.9$\\%$ with CH$_{2}$DOH in pre-stellar cores H-MM1 and L694-2, consistent with measurements in more evolved Class 0/I objects and comet 67P/Churyumov-Gerasimenko, suggesting a direct chemical link arising in the pre-stellar stage. Furthermore, the column density ratios of CHD$_{2}$OH/CH$_{2}$DOH are $\\sim$50-80$\\%$, consistently high as that towards Class 0/I objects, indicating an efficient formation mechanism of CHD$_{2}$OH, possibly through H atom additions to D$_{2}$CO. The CH$_{2}$DOH/CH$_{3}$OH and CHD$_{2}$OH/CH$_{3}$OH column density ratios in the two pre-stellar cores are larger than that in the two starless cores B68 and L1521E, representing an evolutionary trend of methanol deuteration in early-stage cores.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2022-12-19T15:35:50.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "first detection",
      "deuterium fractionation",
      "oh column density ratios",
      "efficient formation mechanism",
      "pre-stellar cores h-mm1"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}