{
  "abstract": "SPHEREx conducts the first all-sky near-infrared spectral survey over 0.75-5.0 $μ$m, spanning the transition from host-galaxy starlight to AGN-heated torus emission and enabling spectroscopic identification of active galactic nuclei (AGNs). We develop a data-driven framework combining weighted non-negative matrix factorization with forward modeling to learn empirical rest-frame templates from 2,777 normal galaxies and 1,064 AGNs in the North Ecliptic Pole (NEP) field. The resulting 14-component dictionary contains seven galaxy templates spanning stellar-population continua and nebular emission and seven AGN templates capturing emission lines and warm and hot torus continua, providing an additive, operational decomposition. Inferred near-infrared host fractions correlate with independent SDSS spectral and HSC imaging decompositions (at Pearson $r=0.68$ and $r=0.59$), comparable to the SDSS-HSC correlation ($r=0.66$) and supporting the reliability of the AGN-host separation. In the NEP deep field, the same templates recover redshifts with $|z_{\\rm fit}-z_{\\rm spec}| < 0.01$ for 93.0% of galaxies and 93.5% of AGNs and distinguish galaxies, narrow-line AGNs, and broad-line AGNs with 81.3% accuracy. At all-sky depth, classification retains 72.9% accuracy. The near-infrared coefficients also flag questionable DESI spectral classifications and redshifts, showing how SPHEREx complements optical spectroscopy. Learned directly from survey spectrophotometry and extending beyond the $K$ band, this empirical dictionary fills a long-standing gap in near-to-mid-infrared templates and provides a data-driven foundation for population-scale studies of AGN activity and its connection to host galaxies across the SPHEREx all-sky survey.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.02167",
  "author_total": 12,
  "authors": [
    {
      "name": "Wenke Ren"
    },
    {
      "name": "Hengxiao Guo"
    },
    {
      "name": "Zhenya Zheng"
    },
    {
      "name": "Minfeng Gu"
    },
    {
      "name": "Wenwen Zuo"
    },
    {
      "name": "Junxian Wang"
    },
    {
      "name": "Weida Hu"
    },
    {
      "name": "Zhen-Bo Su"
    },
    {
      "name": "Shi-Jiang Chen"
    },
    {
      "name": "Lin Long"
    },
    {
      "name": "Jiaqi Lin"
    },
    {
      "name": "Chi-Zhuo Wang"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/7j7m09f383tam.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.02167",
  "fulltext_url": null,
  "id": "7j7m09f383tam",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.02167",
  "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"
    ],
    [
      "arxiv",
      "astro-ph.IM"
    ],
    [
      "openalex",
      "3103|Galaxies: Formation, Evolution, Phenomena"
    ]
  ],
  "openalex": "W7204866414",
  "pdf_url": "https://arxiv.org/pdf/2609.02167",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-02",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/7j7m09f383tam.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:16Z",
      "native_id": "2609.02167",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.02167"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.GA",
      "subfield": "galaxies"
    },
    {
      "field": "astronomy",
      "origin": "arxiv:astro-ph.IM",
      "subfield": "instrumentation-methods"
    }
  ],
  "title": "Empirical Near-Infrared Spectral Templates from SPHEREx: Disentangling AGN and Host-Galaxy Emission",
  "title_text": "Empirical Near-Infrared Spectral Templates from SPHEREx: Disentangling AGN and Host-Galaxy Emission",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:16Z",
  "url": "https://research.draconitic.com/paper/7j7m09f383tam",
  "venue": "arXiv",
  "versions": []
}