  A ring-shaped debris disk around the G2V star HD 202628 (d = 24.4 pc) was
imaged in scattered light at visible wavelengths using the coronagraphic mode
of the Space Telescope Imaging Spectrograph on the Hubble Space Telescope. The
ring is inclined by 64 degrees from face-on, based on the apparent major/minor
axis ratio, with the major axis aligned along PA = 130 degrees. It has inner
and outer radii (>50% maximum surface brightness) of 139 AU and 193 AU in the
northwest ansae and 161 AU and 223 AU in the southeast (dr/r ~ 0.4). The
maximum visible radial extent is ~254 AU. With a mean surface brightnesses of V
~ 24 mag per square arcsec, this is the faintest debris disk observed to date
in reflected light. The center of the ring appears offset from the star by ~28
AU (deprojected). An ellipse fit to the inner edge has an eccentricity of 0.18
and a = 158 AU. This offset, along with the relatively sharp inner edge of the
ring, suggests the influence of a planetary-mass companion. There is a strong
similarity with the debris ring around Fomalhaut, though HD 202628 is a more
mature star with an estimated age of about 2 Gyr.
  We also provide surface brightness limits for nine other stars in our study
with strong Spitzer excesses around which no debris disks were detected in
scattered light (HD 377, HD 7590, HD 38858, HD 45184, HD 73350, HD 135599, HD
145229, HD 187897, and HD 201219).
