{
  "abstract": "The Peanut galaxy cluster (SRGe CL0238.3+2005) offers a rare opportunity to investigate thermal and nonthermal processes only $\\sim0.1$\\,Gyr after pericentric passage. We present a multi-frequency radio study of this system at $z=0.42$ using new MeerKAT and uGMRT observations, complemented by Chandra and MUSTANG-2 data. We identify two morphologically and spectrally distinct radio components: a double-lobed source in the northern subcluster and extended diffuse emission across the cluster center. The double-lobed source has a strongly curved, ultra-steep spectrum and is offset by $\\sim22$\\,kpc from the nearest brightest cluster galaxy. Its spectral curvature and positional offset are consistent with remnant AGN plasma that may have been displaced during the merger or reshaped by a shock. The diffuse emission extends over $\\sim1$~Mpc and is classified as an ultra-steep spectrum ($α=-1.77\\pm0.11$ between 400\\,MHz and 1.28\\,GHz) radio halo. Its volume-averaged radio emissivity, $(1.1\\pm0.1)\\times10^{-41}$ erg s$^{-1}$ cm$^{-3}$ Hz$^{-1}$ at 1.4\\,GHz, is an order of magnitude higher than the characteristic value for other halos. The radial profile of the halo is well described by a single exponential fit and its radio emission correlates tightly with the X-ray, with a best-fit slope of $1.11\\pm0.05$. Chandra and MUSTANG-2 observations reveal candidate surface brightness discontinuities, with the most prominent inner feature coinciding with a region of flatter spectral index, potentially tracing localized particle (re)-acceleration. The coexistence of an extended ultra-steep spectrum radio halo, high radio emissivity, remnant AGN plasma, and candidate X-ray/SZ discontinuities makes the Peanut cluster an important test case for understanding the evolution of diffuse radio emission and its connection to the dynamical state of the intracluster medium in early-stage mergers.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.34667",
  "author_total": 28,
  "authors": [
    {
      "name": "K. Rajpurohit"
    },
    {
      "name": "N. Lyskova"
    },
    {
      "name": "E. Churazov"
    },
    {
      "name": "W. Forman"
    },
    {
      "name": "I. Khabibullin"
    },
    {
      "name": "R. Kraft"
    },
    {
      "name": "L. Di Mascolo"
    },
    {
      "name": "T. Mroczkowski"
    },
    {
      "name": "A. Botteon"
    },
    {
      "name": "C. Jones"
    },
    {
      "name": "E. O'Sullivan"
    },
    {
      "name": "C. Zhang"
    },
    {
      "name": "R. J. van Weeren"
    },
    {
      "name": "I. Zhuravleva"
    },
    {
      "name": "G. Schellenberger"
    },
    {
      "name": "J. M. Vrtilek"
    },
    {
      "name": "L. P. David"
    },
    {
      "name": "R. Sunyaev"
    },
    {
      "name": "M. Devlin"
    },
    {
      "name": "S. Dicker"
    },
    {
      "name": "S. Haridas"
    },
    {
      "name": "J. van Marrewijk"
    },
    {
      "name": "B. S. Mason"
    },
    {
      "name": "E. Moravec"
    },
    {
      "name": "J. Orlowski-Scherer"
    },
    {
      "name": "C. Romero"
    },
    {
      "name": "C. L. Sarazin"
    },
    {
      "name": "J. Sievers"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/c8pyycfh14w5e.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.34667",
  "fulltext_url": null,
  "id": "c8pyycfh14w5e",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.34667",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.CO"
    ],
    [
      "arxiv",
      "astro-ph.GA"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7223938396",
  "pdf_url": "https://arxiv.org/pdf/2610.34667",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-26",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/c8pyycfh14w5e.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:35Z",
      "native_id": "2610.34667",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.34667"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.CO",
      "subfield": "cosmology"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Radio view of the Peanut cluster: merger-induced stripping and a radio halo shortly after pericentric passage",
  "title_text": "Radio view of the Peanut cluster: merger-induced stripping and a radio halo shortly after pericentric passage",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:35Z",
  "url": "https://research.draconitic.com/paper/c8pyycfh14w5e",
  "venue": "arXiv",
  "versions": []
}