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

TL;DR

This paper reports the discovery and characterization of an extended, asymmetric debris disk around the star HD 15745, revealing details about its structure, composition, and possible age, using Hubble Space Telescope observations.

Contribution

First detection of a debris disk around HD 15745 with detailed morphology and dust properties derived from HST imaging.

Findings

Disk extends from 128 to 480 AU.

Disk is asymmetric and fan-shaped.

Dust mass estimated at 0.03 Earth masses.

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.