{
  "id": "2305.05073",
  "version": "v1",
  "published": "2023-05-08T22:21:22.000Z",
  "updated": "2023-05-08T22:21:22.000Z",
  "title": "An analysis of the isomers HCN and HNC in the evolution of high-mass star-forming regions",
  "authors": [
    "N. C. Martinez",
    "S. Paron"
  ],
  "comment": "to appear in Bolet\\'in de la Asociaci\\'on Argentina de Astronom\\'ia",
  "categories": [
    "astro-ph.GA"
  ],
  "abstract": "The study of molecules and their chemistry in star-forming regions is fundamental to understand the physical process occurring in such regions. The HCN and HNC J=1-0 emissions were used to derive their integrated line intensities (I), to probe a relation recently appeared in the literature between the kinetic temperatures (T$_{K}$) and the isomeric (I) ratio, and to obtain the isomers abundances (X) in 55 high-mass star-forming regions. These last ones are classified, according to the evolutive stage, as infrared dark clouds, high-mass protostellar objects, hot molecular cores, and ultracompact HII regions. It is inferred that the T$_{K}$ obtained from the isomeric integrated intensity ratio (I$^{HCN/HNC}$) are underestimated, and hence we suggest that this relation cannot be employed as an universal thermometer in the interstellar medium. The isomers abundances show a behavior that can be explained from the chemistry occurring as the temperature and the UV radiation increase according to the evolutive stage. We found that the abundance ratio (X$^{HCN/HNC}$) hardly could be used as a chemical clock, and we suggest that it can be approximated by I$^{HCN/HNC}$. This work is part of an on-going study of multiple molecules that stand in the sample of analyzed regions which intends to contribute in the chemical knowledge of high-mass star formation.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2023-05-08T22:21:22.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "high-mass star-forming regions",
      "isomers hcn",
      "isomers abundances",
      "uv radiation increase",
      "ultracompact hii regions"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}