2008/05/30 by Steve B. Howell, D. W. Hoard, C. Brinkworth +8
Physics and Astronomy · #Accretion (finance) #Accretion disc #Astronomy #Astrophysical Phenomena and Observations #Astrophysics #Astrophysics and Star Formation Studies #Galaxy #Physics #RADIUS #Spitzer Space Telescope #Stars #Stellar, planetary, and galactic studies #Thick disk #astro-ph
paper · pdf · doi:10.1086/590491
34 pages, 8 figures (3 in color). Accepted to ApJ
arxiv created 2008/05/30 · openalex publication_date 2008/09/18 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Using Spitzer Space Telescope photometric observations of the eclipsing, interacting binary WZ Sge, we have discovered that the accretion disk is far more complex than previously believed. Our 4.5 and 8 μm time series observations reveal that the well-known gaseous accretion disk is surrounded by an asymmetric disk of dusty material with a radius approximately 15 times larger than the gaseous disk. This dust ring contains only a small amount of mass and is completely invisible at optical and near-IR wavelengths, hence consisting of "dark matter." We have produced a model dust ring using 1 μm spherical particles with a density of 3 g cm −3 and with a temperature profile ranging from 700 to 1500 K. Our discovery about the accretion disk structure and the presence of a larger, outer dust ring have great relevance for accretion disks in general, including those in other interacting binary systems, pre-main-sequence stars, and active galaxies.