{
  "abstract": "An explorative study of Type Ia supernovae (SNe Ia) light curves is presented. $\\Delta m_t(X)$ decline-rate metrics are used to evaluate alternative characterisations of light-curve diversity and the luminosity–width relation (LWR). Using a sample of 362 SNe Ia from the Carnegie Supernova Project (CSP-I and CSP-II), Gaussian process regression is used to fit B- and g-band light curves and measure decline-rates across multiple post-maximum time-scales. The LWR is calibrated using a clean subsample of SNe Ia with host-independent distance moduli and Fitzpatrick (1999) reddening corrections. Decline-rates $\\Delta m_{10}(B)$ and $\\Delta m_{10}(g)$ are found to capture the LWR effectively, while mitigating the severe degeneracy that affects longer time-scales for fast-declining ($\\Delta m_{15}(B) \\ge 1.6\\, \\text{mag}$) events. Continuous, piecewise linear models are presented that seamlessly anchor the transition between normal and fast-declining regimes. The decline-rate $\\Delta m_{10}(X)$ closely approximates the results of the more complex colour-stretch parameters, requiring less post-maximum temporal coverage than $\\Delta m_{15}(B)$ or $s_{BV}$, and offers an even greater sensitivity for slow decliners. $\\Delta m_{10}(B)$ provides a precise and practical tool for large-scale photometric surveys and real-time observer classification.",
  "abstract_shown": true,
  "affiliations": [
    "Astrophysics Research Institute, Liverpool John Moores University , IC2, Liverpool Science Park, 146 Brownlow Hill, Liverpool L3 5RF ,",
    "Max-Planck-Institut für Astrophysik , Karl-Schwarzschild-Str 1, D-85748 Garching ,",
    "Institute for Astronomy, University of Hawaii , 2680 Woodlawn Dr, Honolulu, HI 96822 ,",
    "Observatories of the Carnegie Institution for Science , 813 Santa Barbara St, Pasadena, CA 91101 ,",
    "Carnegie Observatories , Las Campanas Observatory, Colina El Pino, Casilla 601 ,",
    "Institute of Space Sciences (ICE-CSIC) , Campus UAB, Carrer de Can Magrans, s/n, E-08193 Barcelona ,",
    "Institut d’Estudis Espacials de Catalunya (IEEC) , E-08860 Castelldefels (Barcelona) ,",
    "Department of Physics and Astronomy, Aarhus University , Ny Munkegade 120, DK-8000 Aarhus C ,",
    "Department of Physics, Florida State University , 77 Chieftan Way, Tallahassee, FL 32306 ,",
    "Center for Astronomy, Space Science and Astrophysics, Independent University , Bashundhara R/A, Dhaka 1229 ,",
    "American Public University System , 111 W. Congress St, Charles Town, WV 25414 ,"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 11,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Joel M Velasco",
      "orcid": "0009-0000-5092-4090"
    },
    {
      "affs": [
        0,
        1
      ],
      "name": "Paolo A Mazzali",
      "orcid": "0000-0001-6876-8284"
    },
    {
      "affs": [
        2
      ],
      "name": "Christopher Ashall",
      "orcid": "0000-0002-5221-7557"
    },
    {
      "affs": [
        3
      ],
      "name": "Christopher R Burns",
      "orcid": "0000-0003-4625-6629"
    },
    {
      "affs": [
        4
      ],
      "name": "Mark M Phillips",
      "orcid": "0000-0003-2734-0796"
    },
    {
      "affs": [
        5,
        6
      ],
      "name": "Lluis Galbany",
      "orcid": "0000-0002-1296-6887"
    },
    {
      "affs": [
        4
      ],
      "name": "Nidia Morrell",
      "orcid": "0000-0003-2535-3091"
    },
    {
      "affs": [
        7
      ],
      "name": "Maximilian D Stritzinger",
      "orcid": "0000-0002-5571-1833"
    },
    {
      "affs": [
        8
      ],
      "name": "Peter Hoeflich",
      "orcid": "0000-0002-4338-6586"
    },
    {
      "affs": [
        8
      ],
      "name": "Eric Y Hsiao",
      "orcid": "0000-0003-1039-2928"
    },
    {
      "affs": [
        9,
        10
      ],
      "name": "Syed A Uddin",
      "orcid": "0000-0002-9413-4186"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/35ryjvwxscmwq.bib",
  "cited_by": 0,
  "doi": "10.1093/mnras/stag1907",
  "fulltext_url": null,
  "id": "35ryjvwxscmwq",
  "issns": [
    "0035-8711",
    "1365-2966"
  ],
  "landing_url": "https://academic.oup.com/mnras/article/doi/10.1093/mnras/stag1907/8876083",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
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      "openalex",
      "3103|Gamma-ray bursts and supernovae"
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  "pdf_url": "https://academic.oup.com/mnras/advance-article-pdf/doi/10.1093/mnras/stag1907/71668211/stag1907.pdf",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-07",
  "publisher": "Oxford University Press (OUP)",
  "ris": "https://research.draconitic.com/paper/35ryjvwxscmwq.ris",
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    {
      "first_seen": "2026-10-30T12:18:17Z",
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  "subjects": [
    {
      "field": "astronomy",
      "origin": "openalex:3103|Gamma-ray bursts and supernovae",
      "subfield": "high-energy-astrophysics"
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  ],
  "title": "Shortening the baseline: characterising Type Ia supernovae using Δ m 10( X )",
  "title_text": "Shortening the baseline: characterising Type Ia supernovae using Δ m 10( X )",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T12:18:17Z",
  "url": "https://research.draconitic.com/paper/35ryjvwxscmwq",
  "venue": "Monthly Notices of the Royal Astronomical Society",
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      "doi": "10.48550/arxiv.2610.10815",
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      "relation": "preprint",
      "title": "Shortening the Baseline: Characterising Type Ia Supernovae Using $Δm_{10}(X)$",
      "venue": "arXiv"
    }
  ]
}