{
  "id": "2406.18646",
  "version": "v1",
  "published": "2024-06-26T18:00:01.000Z",
  "updated": "2024-06-26T18:00:01.000Z",
  "title": "Using 3.4-$μ$m Variability towards White Dwarfs as a Signpost of Remnant Planetary Systems",
  "authors": [
    "Joseph A. Guidry",
    "J. J. Hermes",
    "Kishalay De",
    "Lou Baya Ould Rouis",
    "Brison B. Ewing",
    "B. C. Kaiser"
  ],
  "comment": "27 pages, 8 figures, accepted to The Astrophysical Journal. Supplemental catalogs and light curves available at https://zenodo.org/doi/10.5281/zenodo.12538705",
  "categories": [
    "astro-ph.SR",
    "astro-ph.EP",
    "astro-ph.IM"
  ],
  "abstract": "Roughly 2% of white dwarfs harbor planetary debris disks detectable via infrared excesses, but only a few percent of these disks show a gaseous component, distinguished by their double-peaked emission at the near-infrared calcium triplet. Previous studies found most debris disks around white dwarfs are variable at 3.4 and 4.5 $\\mu$m, but they analyzed only a few of the now 21 published disks showing calcium emission. To test if most published calcium emission disks exhibit large-amplitude stochastic variability in the near-infrared, we use light curves generated from the unWISE images at 3.4 $\\mu$m that are corrected for proper motion to characterize the near-infrared variability of these disks against samples of disks without calcium emission, highly variable cataclysmic variables, and 3215 isolated white dwarfs. We find most calcium emission disks are extremely variable: 6/11 with sufficient signal-to-noise show high-amplitude variability in their 3.4-$\\mu$m light curves. These results lend further credence to the notion that disks showing gaseous debris in emission are the most collisionally active. Under the assumption that 3.4-$\\mu$m variability is characteristic of white dwarfs with dusty debris disks, we generate a catalog of 104 high-confidence near-infrared variable white dwarfs, 84 of which are published as variable for the first time. We do near-infrared spectroscopic follow-up of seven new candidate 3.4-$\\mu$m variables, confirming at least one new remnant planetary system, and posit that empirical near-infrared variability can be a discovery engine for debris disks showing gaseous emission.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2024-06-26T18:00:01.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "white dwarfs",
      "remnant planetary system",
      "variability",
      "harbor planetary debris disks",
      "dwarfs harbor planetary debris"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 27,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}