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Arxiv: Subtle and Spectacular: Diverse White Dwarf Debris Disks Revealed by JWST Published: 1/30/2025 3:35:17 PM Updated: 1/30/2025 3:35:17 PM
Paper abstract: This letter reports 12 novel spectroscopic detections of warm circumstellardust orbiting polluted white dwarfs using JWST MIRI. The disks span two ordersof magnitude in fractional infrared brightness and more than double the numberof white dwarf dust spectra available for mineralogical study. Among thehighlights are: i) the two most subtle infrared excesses yet detected, ii) thestrongest silicate emission features known for any debris disk orbiting anymain-sequence or white dwarf star, iii) one disk with a thermal continuum butno silicate emission, and iv) three sources with likely spectral signatures ofsilica glass. The near ubiquity of solid-state emission requires small dustgrains that are optically thin, and thus must be replenished on year-to-decadetimescales by ongoing collisions. The disk exhibiting a featureless continuumcan only be fit by dust temperatures in excess of 2000K, implying highlyrefractory material comprised of large particles, or non-silicate mineralspecies. If confirmed, the glassy silica orbiting three stars could beindicative of high-temperature processes and subsequent rapid cooling, such asoccur in high-velocity impacts or vulcanism. These detections have been enabledby the unprecedented sensitivity of MIRI LRS spectroscopy and highlight thecapability and potential for further observations in future cycles.
