{
  "id": "2407.17359",
  "version": "v1",
  "published": "2024-07-24T15:30:49.000Z",
  "updated": "2024-07-24T15:30:49.000Z",
  "title": "Simulated [CII] in high-z galaxies",
  "authors": [
    "N. Muñoz-Elgueta",
    "F. Arrigoni Battaia",
    "G. Kauffmann",
    "R. Pakmor",
    "S. Walch",
    "A. Obreja",
    "L. Buhlmann"
  ],
  "comment": "Accepted on July 23, A&A. 17 pages, 16 figures",
  "categories": [
    "astro-ph.GA",
    "astro-ph.CO"
  ],
  "abstract": "Extended [CII] emission on tens of kpc, also known as a [CII] halo, is being currently reported around z$\\sim$4-6 star-forming galaxies, especially thanks to the statistics of the ALPINE survey. The [CII] emission is expected to trace dense cold gas in the inner CGM of these galaxies. The origin of this emission is still debated. In this paper, we present a post-processing model applied to Illustris-TNG50 star-forming galaxies at $z\\sim$4-6, and we compare our results with the ALPINE observations. By incorporating C$^{+}$ abundances derived from UV background and young stars as radiation sources, we generate mock observations, from which we extract surface-brightness (SB) profiles. We found that our model predicts similar [CII] emission values on galactic scales as the observations, providing validation for our approach. However, we find that the predicted [CII] emission in the inner circumgalactic medium (CGM) falls below the observed values by a factor of $\\sim$10. We discuss several model limitations that may contribute to this discrepancy. We also find discrepancies with observations when comparing SB profiles of low and high-SFR galaxies. Unlike the observations, simulations exhibit no discernible difference in the extended [CII] emission between the two subsamples. This discrepancy may reflect shortcomings in feedback model of the simulation. Finally, our analysis suggests that the extended [CII] emission is likely a result of both gas from satellite galaxies and outflows from central galaxies, with satellites playing a dominant role within 0.6$<$R/R$_{\\rm vir}<$1. A firm estimate of the importance of each contribution is beyond the scope of the current simulations.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2024-07-24T15:30:49.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "high-z galaxies",
      "trace dense cold gas",
      "discrepancy",
      "star-forming galaxies",
      "inner circumgalactic medium"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 17,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}