Deep HST/STIS Visible-Light Imaging of Debris Systems around Solar Analog Hosts
Glenn Schneider, Carol A. Grady, Christopher C. Stark, Andras Gaspar, Joseph Carson, John H. Debes, Thomas Henning, Dean C. Hines, Hannah Jang-Condell, Marc J. Kuchner, Marshall Perrin, Timothy J. Rodigas, Motohide Tamura, John P. Wisniewski
(Submitted on 31 May 2016)
We present new Hubble Space Telescope observations of three a priori known starlight-scattering circumstellar debris systems (CDSs) viewed at intermediate inclinations around nearby close-solar analog stars: HD 207129, HD 202628, and HD 202917. Each of these CDSs possesses ring-like components that are more-massive analogs of our solar system’s Edgeworth- Kuiper belt. These systems were chosen for follow-up observations to provide higher-fidelity and better sensitivity imaging for the sparse sample of solar-analog CDSs that range over two decades in systemic ages with HD 202628 and HD 202917 (both ~ 2.3 Gyr) currently the oldest CDSs imaged in visible or near-IR light. These deep (10 – 14 ksec) observations, with six-roll point-spread-function template subtracted visible-light coronagraphy using the Space Telescope Imaging Spectrograph, were designed to better reveal their angularly large, diffuse/low surface brightness, debris rings, and for all targets probe their exo-ring environments for starlight-scattering materials that present observational challenges for current ground-based facilities and instruments. Contemporaneously also observing with a narrower occulter position, these observations additionally probe the CDS endo-ring environments seen to be relatively devoid of scatterers. We discuss the morphological, geometrical, and photometric properties of these CDSs also in the context of other FGK-star hosted CDSs we have previously imaged as a homogeneously observed ensemble. From this combined sample we report a general decay in quiescent disk F_disk/F_star optical brightness ~ t^-0.8, similar to what is seen in at thermal IR wavelengths, and CDSs with a significant diversity in scattering phase asymmetries, and spatial distributions of their starlight-scattering grains.
Comments: 58 pages, 16 figures, accepted for publication in the Astronomical Journal
Subjects: Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:1606.00039 [astro-ph.SR]
(or arXiv:1606.00039v1 [astro-ph.SR] for this version)
Submission history
From: Glenn Schneider
[v1] Tue, 31 May 2016 20:45:24 GMT (2473kb)
http://arxiv.org/abs/1606.00039
