{
  "abstract": "The recent star-formation activity in galaxies can be optimally traced by the H$α$ emission line, with the resulting H$α$ luminosity function (LF) at a given epoch providing a reliable probe of cosmic star formation. We present the first narrow-band determined H$α$ LF into the Epoch of Reionization (EoR) at $z\\sim6.1$, using 39 H$α$ emitters selected from the JWST Emission Line Survey (JELS). The observed and dust-corrected LFs are broadly consistent with recent slitless spectroscopic measurements but show notable discrepancies with predictions from cosmological simulations, likely reflecting differences in emission-line and dust modelling. Fits combining multiple LF datasets help constrain the high-redshift faint-end slope of the H$α$ LF ($-1.79<α_{\\rm{Hα}}<-1.62$), but there remains uncertainty in its evolution with redshift. Integrating the JELS dust-corrected H$α$ LFs yields a star-formation rate density of $\\log_{10}(ρ_{\\rm{SFR_{Hα}}}\\,/\\,\\rm{M_{\\odot}\\,yr^{-1}\\,Mpc^{-3}})=-1.93\\,^{+0.14}_{-0.12}$ or $-2.00\\,^{+0.16}_{-0.10}$, assuming a continuum-to-line extinction ratios $η_{\\rm{dust}}=A_{\\rm{cont}}(\\rm{6563\\,\\mathring{A}})/A_{\\rm{Hα}}=1$ and 0.44, respectively. Both measurements are consistent within uncertainties with previous results using standard assumptions for the LF integration limit ($L_{\\rm{Hα,\\,lim}}$) and SFR calibration constant $κ_{\\rm{Hα}}$, despite the uncertainties in the dust corrections. We explore the metallicity dependence of $κ_{\\rm{Hα}}$ and find $ρ_{\\rm{SFR_{Hα}}}$ decreases 0.43 dex compared to the fiducial result and is no longer consistent with UV-determined $ρ_{\\rm{SFR}}$ at $z\\sim6$. This work highlights the importance of narrow-band surveys in probing the faint H$α$ population and providing new constraints on cosmic star-formation activity into the EoR.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.01586",
  "author_total": 22,
  "authors": [
    {
      "name": "C. A. Pirie"
    },
    {
      "name": "K. J. Duncan"
    },
    {
      "name": "P. N. Best"
    },
    {
      "name": "D. J. McLeod"
    },
    {
      "name": "C. L. Hale"
    },
    {
      "name": "R. K. Cochrane"
    },
    {
      "name": "S. R. Flury"
    },
    {
      "name": "H. M. O. Stephenson"
    },
    {
      "name": "M. I. Arnaudova"
    },
    {
      "name": "M. Brinch"
    },
    {
      "name": "J. S. Dunlop"
    },
    {
      "name": "E. Ibar"
    },
    {
      "name": "Z Li"
    },
    {
      "name": "J. Matthee"
    },
    {
      "name": "R. J. McLure"
    },
    {
      "name": "L. Ossa-Fuentes"
    },
    {
      "name": "A. L. Patrick"
    },
    {
      "name": "J. Selfridge"
    },
    {
      "name": "Ian Smail"
    },
    {
      "name": "D. Sobral"
    },
    {
      "name": "J. P. Stott"
    },
    {
      "name": "A. M. Swinbank"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8mxxnr5dv65t1.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.01586",
  "fulltext_url": null,
  "id": "8mxxnr5dv65t1",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.01586",
  "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.GA"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7206156357",
  "pdf_url": "https://arxiv.org/pdf/2609.01586",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8mxxnr5dv65t1.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:00Z",
      "native_id": "2609.01586",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.01586"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    }
  ],
  "title": "The JWST Emission Line Survey (JELS): A narrow-band determination of the H$α$ Luminosity Function and Cosmic Star Formation into the Epoch of Reionization",
  "title_text": "The JWST Emission Line Survey (JELS): A narrow-band determination of the Hα Luminosity Function and Cosmic Star Formation into the Epoch of Reionization",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:00Z",
  "url": "https://research.draconitic.com/paper/8mxxnr5dv65t1",
  "venue": "arXiv",
  "versions": []
}