Activity in White Dwarf Debris Disks II: WISE Mission Traces a Decade of Disk Evolution and Persistence
Abstract
This study presents multi-epoch photometry from the Wide-field Infrared Survey Explorer to investigate variability in white dwarf debris disks, utilizing the full 14.5 yr mission datasets pre- and post-cryogen. Unambiguous variations are detected across the bulk of the 52 confirmed dusty white dwarfs and are consistent with universal variability after correcting for the sensitivity of WISE relative to Spitzer. Some disk light curves exhibit trends such as possible oscillations, sudden brightening, and steadily decaying fluxes, but all infrared excesses persist utterly. On baselines longer than 0.5 yr, flux changes are significantly skewed toward decreases, in contrast to the symmetric distribution found at shorter baselines with Spitzer, consistent with gradual dust depletion over time. Disk emission generally becomes redder when dimmer and bluer when brighter, consistent with changes in the grain size distribution following collisions, although five disks exhibit the opposite trend possibly due to dust production near apastron. A moderate positive correlation is observed between disk luminosity and photospheric Ca abundance, consistent with the accretion of disk material in an optically thin configuration. Taken together with the Spitzer legacy of dusty white dwarfs, these results provide a comprehensive view of debris disk variability and provide empirical constraints on models of disk structure and evolution.
Related
- 3.5-meter Segmented-Mirror Robotic Space Telescope Mission White Paper II. Key Scientific Mission: Wide-Field Cosmology and Galaxy Evolution
- Migration and Evolution of giant ExoPlanets (MEEP). III. Twenty-Nine Giant Planets from the TESS Mission
- Evolution of Stellar Activity and Habitable Zone. IV. Calcium II Infrared Triplet Activity from Open Clusters and White Dwarf Binaries
- Evolution of Stellar Activity and Habitable Zone (EATEN): III. X-ray Activity of Dwarfs in Open Clusters and Field Stars
- Evolution of Stellar Activity and Habitable Zone. III. X-Ray Activity of Dwarfs in Open Clusters and Field Stars
BibTeX
@misc{noor2026activity,
title = {{Activity in White Dwarf Debris Disks II: WISE Mission Traces a Decade of Disk Evolution and Persistence}},
author = {Hiba Tu Noor and Jay Farihi and Scott J. Kenyon},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2609.34868},
eprint = {2609.34868},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2609.34868},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Activity in White Dwarf Debris Disks II: WISE Mission Traces a Decade of Disk Evolution and Persistence
AU - Hiba Tu Noor
AU - Jay Farihi
AU - Scott J. Kenyon
PY - 2026
DA - 2026/09/28
PB - arXiv
DO - 10.48550/arxiv.2609.34868
UR - https://arxiv.org/abs/2609.34868
AB - This study presents multi-epoch photometry from the Wide-field Infrared Survey Explorer to investigate variability in white dwarf debris disks, utilizing the full 14.5 yr mission datasets pre- and post-cryogen. Unambiguous variations are detected across the bulk of the 52 confirmed dusty white dwarfs and are consistent with universal variability after correcting for the sensitivity of WISE relative to Spitzer. Some disk light curves exhibit trends such as possible oscillations, sudden brightening, and steadily decaying fluxes, but all infrared excesses persist utterly. On baselines longer than 0.5 yr, flux changes are significantly skewed toward decreases, in contrast to the symmetric distribution found at shorter baselines with Spitzer, consistent with gradual dust depletion over time. Disk emission generally becomes redder when dimmer and bluer when brighter, consistent with changes in the grain size distribution following collisions, although five disks exhibit the opposite trend possibly due to dust production near apastron. A moderate positive correlation is observed between disk luminosity and photospheric Ca abundance, consistent with the accretion of disk material in an optically thin configuration. Taken together with the Spitzer legacy of dusty white dwarfs, these results provide a comprehensive view of debris disk variability and provide empirical constraints on models of disk structure and evolution.
ER -