{
  "abstract": "Measurements of the entropy and temperature distribution of the intracluster medium (ICM) of local clusters have proven pivotal for the study of cluster astrophysics. Here, we extend these measurements to $z=1.7$ with a resolved analysis of the ICM in ACT/SPT-CL J0459.6-4946. By combining high-resolution thermal Sunyaev-Zeldovich measurements using new, deep ALMA Band 1 and 3 observations, with archival X-ray data, we conclude that the cluster has (i) an ICM with a flat and relatively high ($\\approx 200$ keV cm$^2$) entropy distribution out to $\\approx 0.3\\,r_{500,\\mathrm{c}}$, (ii) a hot core ($T_{\\mathrm{e}} \\simeq 14$ keV) with a declining temperature profile, (iii) a short effective path length along the line of sight of $l_{\\mathrm{eff}} \\simeq (0.75 \\pm 0.05) \\times r_{500,\\mathrm{c}}$, and (iv) a clumpiness factor $C = \\langle n_{\\mathrm{e}}^2 \\rangle / \\langle n_{\\mathrm{e}} \\rangle^2 \\simeq 1.17 \\pm 0.05$ within $r_{500,\\mathrm{c}}$. Its dynamic nature and high redshift suggest that the cluster is still thermalising its ICM, consistent with a relatively large hydrostatic mass bias of $b = 1 - M_{500,\\mathrm{c,HE}}/M_{500,\\mathrm{c,WL}} = 0.27^{+0.32}_{-0.67}$ that we measure with respect to the weak lensing mass. Furthermore, a region with low entropy and high density to the south of the cluster centre is observed in the X-rays yet absent in the Compton-$y$ map, indicating pressure equilibrium; we interpret this as a sloshing cold front -- the first such detection at high redshifts. This case study demonstrates that $\\approx 3$h-long ALMA observations, combined with comparatively \"short\" X-ray exposures ($\\approx 122$ ks), can fully characterise the ICM at high redshift, opening a path towards the thermodynamics of young and distant galaxy clusters for larger samples.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.00132",
  "author_total": 26,
  "authors": [
    {
      "name": "J. van Marrewijk"
    },
    {
      "name": "L. Di Mascolo"
    },
    {
      "name": "S. Ueda"
    },
    {
      "name": "T. Mroczkowski"
    },
    {
      "name": "T. Akahori"
    },
    {
      "name": "E. S. Battistelli"
    },
    {
      "name": "M. J. Devlin"
    },
    {
      "name": "A. Flores"
    },
    {
      "name": "A. S. Gill"
    },
    {
      "name": "F. A. Gómez"
    },
    {
      "name": "M. Hilton"
    },
    {
      "name": "J. P. Hughes"
    },
    {
      "name": "T. Kitayama"
    },
    {
      "name": "Y. -T. Lin"
    },
    {
      "name": "K. Moodley"
    },
    {
      "name": "N. Okabe"
    },
    {
      "name": "M. Pannella"
    },
    {
      "name": "B. Ried Guachalla"
    },
    {
      "name": "H. Röttgering"
    },
    {
      "name": "J. S. Sanders"
    },
    {
      "name": "A. Saro"
    },
    {
      "name": "C. Sifón"
    },
    {
      "name": "V. Strazzullo"
    },
    {
      "name": "M. Takizawa"
    },
    {
      "name": "E. J. Wollack"
    },
    {
      "name": "X. Zhang"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/5jftr8rk8jf40.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.00132",
  "fulltext_url": null,
  "id": "5jftr8rk8jf40",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.00132",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.CO"
    ],
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "arxiv",
      "astro-ph.HE"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.00132",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/5jftr8rk8jf40.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:20:59Z",
      "native_id": "2611.00132",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.00132"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.HE",
      "subfield": "high-energy-astrophysics"
    }
  ],
  "title": "Galaxy cluster thermodynamics at z=1.7: Resolved tSZ and X-ray analysis of CL J0459.6-4946",
  "title_text": "Galaxy cluster thermodynamics at z=1.7: Resolved tSZ and X-ray analysis of CL J0459.6-4946",
  "type": "preprint",
  "updated_at": "2026-11-05T15:20:18Z",
  "url": "https://research.draconitic.com/paper/5jftr8rk8jf40",
  "venue": "arXiv",
  "versions": []
}