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arXiv · 0712.0378

Discovery of an extended debris disk around the F2V star HD 15745

Paul Kalas·Gaspard Duchene·Michael P. Fitzgerald·James R. Graham
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Abstract

Using the Advanced Camera for Surveys aboard the Hubble Space Telescope, we have discovered dust-scattered light from the debris disk surrounding the F2V star HD 15745. The circumstellar disk is detected between 2.0" and 7.5" radius, corresponding to 128 - 480 AU radius. The circumstellar disk morphology is asymmetric about the star, resembling a fan, and consistent with forward scattering grains in an optically thin disk with an inclination of ~67 degrees to our line of sight. The spectral energy distribution and scattered light morphology can be approximated with a model disk composed of silicate grains between 60 and 450 AU radius, with a total dust mass of 10E-7 M_sun (0.03 M_earth) representing a narrow grain size distribution (1 - 10 micron). Galactic space motions are similar to the Castor Moving Group with an age of ~10E+8 yr, although future work is required to determine the age of HD 15745 using other indicators.

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Paul Kalas, Gaspard Duchene, Michael P. Fitzgerald, James R. Graham. 2007-12-03. Discovery of an extended debris disk around the F2V star HD 15745. https://doi.org/10.1086/525252

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