{
  "abstract": "Atmospheric escape shapes close-in planets mostly in their first tens of Myr. The young V1298Tau system (10-30Myr) is a benchmark for investigating photoevaporation and planetary evolution at early stages. The metastable HeI near-infrared triplet is a key proxy for atmospheric escape. We aim to detect and characterise HeI in the extended atmosphere of V1298Taub. We analysed four transits over a 4-year baseline using GIARPS (GIANO-B + HARPS-N) at the Telescopio Nazionale Galileo. We re-derived the projected spin-orbit angle by modelling the Rossiter-McLaughlin effect. Using simultaneous optical and near-infrared high-resolution transmission spectroscopy of V1298Taub, we monitored the HeI triplet alongside key chromospheric indicators ($\\log R'_{HK}$, H$α$, and NaI) to disentangle stellar activity from planetary evaporation. While the stellar spectra show significant night-to-night variability, transmission spectroscopy reveals persistent HeI absorption across all four epochs. This contrasts with H$α$ and NaI, observed over two nights with simultaneous HARPS-N monitoring, which fluctuate between emission and absorption due to stellar activity. The consistent presence of HeI over 4 years may suggest a planetary origin, despite stellar-driven depth modulation. ATES hydrodynamic simulations show that stellar XUV flux variations modulate the HeI absorption depth and equivalent width. Furthermore, stellar wind fluctuations likely drive the observed night-to-night variability of the exospheric structure. The detection of HeI across all epochs may support planetary evaporation, despite modulation by stellar activity. Our results underscore that disentangling a planetary signal from stellar contamination remains challenging for highly active hosts; securing the planetary nature of the HeI signature requires activity monitoring and full transit coverage to establish a robust baseline.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.32815",
  "author_total": 40,
  "authors": [
    {
      "name": "G. Guilluy"
    },
    {
      "name": "J. Orell-Miquel"
    },
    {
      "name": "A. Sozzetti"
    },
    {
      "name": "M. C. D'Arpa"
    },
    {
      "name": "N. Greco"
    },
    {
      "name": "A. F. Lanza"
    },
    {
      "name": "D. Sicilia"
    },
    {
      "name": "A. Caldiroli"
    },
    {
      "name": "R. Spinelli"
    },
    {
      "name": "D. Locci"
    },
    {
      "name": "P. Leonardi"
    },
    {
      "name": "L. Mancini"
    },
    {
      "name": "S. Colombo"
    },
    {
      "name": "M. Rainer"
    },
    {
      "name": "F. Borsa"
    },
    {
      "name": "A. Maggio"
    },
    {
      "name": "A. S. Bonomo"
    },
    {
      "name": "L. Affer"
    },
    {
      "name": "V. Andretta"
    },
    {
      "name": "F. Biassoni"
    },
    {
      "name": "A. Bignamini"
    },
    {
      "name": "W. Boschin"
    },
    {
      "name": "M. Brogi"
    },
    {
      "name": "C. Di Maio"
    },
    {
      "name": "L. Fossati"
    },
    {
      "name": "E. Gallo"
    },
    {
      "name": "F. Haardt"
    },
    {
      "name": "M. López-Puertas"
    },
    {
      "name": "V. Lorenzi"
    },
    {
      "name": "L. Malavolta"
    },
    {
      "name": "J. Maldonaldo"
    },
    {
      "name": "F. Manni"
    },
    {
      "name": "G. Micela"
    },
    {
      "name": "F. Murgas"
    },
    {
      "name": "V. Nascimbeni"
    },
    {
      "name": "E. Palle"
    },
    {
      "name": "J. Sanz-Forcada"
    },
    {
      "name": "G. Scandariato"
    },
    {
      "name": "J. Southworth"
    },
    {
      "name": "J. Tregloan-Reed"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/1jgdvngt7sdhh.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.32815",
  "fulltext_url": null,
  "id": "1jgdvngt7sdhh",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.32815",
  "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.EP"
    ],
    [
      "openalex",
      "3103|Stellar, planetary, and galactic studies"
    ]
  ],
  "openalex": "W7223687013",
  "pdf_url": "https://arxiv.org/pdf/2610.32815",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-23",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/1jgdvngt7sdhh.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:35:15Z",
      "native_id": "2610.32815",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.32815"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.EP",
      "subfield": "planetary"
    }
  ],
  "title": "The GAPS Programme at TNG LXXXI. The puzzle of the HeI absorption signal in the atmosphere of V1298 Tau b with GIARPS@TNG",
  "title_text": "The GAPS Programme at TNG LXXXI. The puzzle of the HeI absorption signal in the atmosphere of V1298 Tau b with GIARPS@TNG",
  "type": "preprint",
  "updated_at": "2026-10-30T12:35:15Z",
  "url": "https://research.draconitic.com/paper/1jgdvngt7sdhh",
  "venue": "arXiv",
  "versions": []
}