  We present new high resolution imaging of a light-scattering dust ring and
halo around the young star HD 35841. Using spectroscopic and polarimetric data
from the Gemini Planet Imager in H-band (1.6 microns), we detect the highly
inclined (i=85 deg) ring of debris down to a projected separation of ~12 au
(~0.12") for the first time. Optical imaging from HST/STIS shows a smooth dust
halo extending outward from the ring to >140 au (>1.4"). We measure the ring's
scattering phase function and polarization fraction over scattering angles of
22-125 deg, showing a preference for forward scattering and a polarization
fraction that peaks at ~30% near the ansae. Modeling of the scattered-light
disk indicates that the ring spans radii of ~60-220 au, has a vertical
thickness similar to that of other resolved dust rings, and contains grains as
small as 1.5 microns in diameter. These models also suggest the grains have a
low porosity, are more likely to consist of carbon than astrosilicates, and
contain significant water ice. The halo has a surface brightness profile
consistent with that expected from grains pushed by radiation pressure from the
main ring onto highly eccentric but still bound orbits. We also briefly
investigate arrangements of a possible inner disk component implied by our
spectral energy distribution models, and speculate about the limitations of Mie
theory for doing detailed analyses of debris disk dust populations.
