{
  "abstract": "The fraction of quenched galaxies increases with local density, and part of this trend is thought to arise in groups before cluster accretion (pre-processing). In merging clusters, this is difficult to separate from star formation triggered or suppressed by the cluster merger itself. We investigate whether five high-velocity galaxies in the merging cluster SPT-CL~J0307-6225 ($z=0.579$), distributed in two candidate infalling groups, show signs of group-scale environmental processing prior to accretion. We combine MUSE integral-field spectroscopy and HST imaging to derive [\\ion{O}{ii}] kinematic maps, spectral classes, and star-formation rates (SFR), to understand the properties of the galaxies. We further use the Magneticum simulations and the phase-space information to determine if these galaxies are part of two groups, and if they will be accreted onto the merging cluster. Group~1 is a morphologically disturbed interacting pair bound to the cluster, with at least one galaxy classified as dusty starburst. Group~2 is a compact triplet at $\\sim$4$σ_v$ from the cluster, in which two galaxies share a common [\\ion{O}{ii}] envelope and the dominant member, an e(b) starburst, shows an elevated ionised-gas velocity dispersion. The SFR of both starburst galaxies lie within the scatter of the field star-forming main sequence, as expected for modest, interaction-triggered bursts. Close pairs at the phase-space position of group~2 occur for $\\sim$1\\% of comparable-mass cluster galaxies in Magneticum, so it is not unlikely for the group to be bound. Both groups show spatially resolved signatures of galaxy--galaxy interactions alongside ongoing star formation, supporting a pre-processing scenario in the environment of a merging cluster. Such group-scale interactions may contribute to the enhanced star formation reported in merging clusters.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.01344",
  "author_total": 15,
  "authors": [
    {
      "name": "D. Hernández-Lang"
    },
    {
      "name": "D. Pallero"
    },
    {
      "name": "A. Ivleva"
    },
    {
      "name": "E. Sextl"
    },
    {
      "name": "N. Muñoz-Elgueta"
    },
    {
      "name": "J. Pierel"
    },
    {
      "name": "A. Zenteno"
    },
    {
      "name": "M. Bayliss"
    },
    {
      "name": "A. Calamida"
    },
    {
      "name": "E. R. Carrasco"
    },
    {
      "name": "G. Mahler"
    },
    {
      "name": "R. Monteiro-Oliveira"
    },
    {
      "name": "P. H. Prado"
    },
    {
      "name": "A. Rest"
    },
    {
      "name": "A. Saro"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/f38wtwrspzcfz.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.01344",
  "fulltext_url": null,
  "id": "f38wtwrspzcfz",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.01344",
  "language": null,
  "licence": "CC-BY-NC-ND-4.0",
  "licence_label": "CC BY-NC-ND 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by-nc-nd/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "astro-ph.GA"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.01344",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/f38wtwrspzcfz.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:20:59Z",
      "native_id": "2611.01344",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.01344"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "Witnessing pre-processing at intermediate redshift: observational evidence of infalling groups onto a merging galaxy cluster",
  "title_text": "Witnessing pre-processing at intermediate redshift: observational evidence of infalling groups onto a merging galaxy cluster",
  "type": "preprint",
  "updated_at": "2026-11-05T15:20:18Z",
  "url": "https://research.draconitic.com/paper/f38wtwrspzcfz",
  "venue": "arXiv",
  "versions": []
}