ARCSAT ID NUMBER: AS09

DESCRIPTIVE TITLE: Stellar Environments of the Nearest G and K Stars

PI: Michele Silverstein (GSU)

OBSERVER(S): Michele Silverstein (GSU) and Todd Henry (GSU)

UNCERTIFIED/UNTRAINED OBSERVERS: Michele Silverstein and Todd Henry

COLLABORATORS: Wei-Chun Jao (GSU), Jen Winters (GSU)

CONTACT INFORMATION: (PI/OBSERVER email/phone)
silverstein@astro.gsu.edu (404-413-6014), thenry@astro.gsu.edu
(404-413-6054)

TIME REQUESTED:

1. JULY 21-27

2. SEPTEMBER 15-21 or SEPTEMBER 22-28

Two weeks requested a few months apart to expand sky coverage at
targets, which are at all RA, and to allow for some stars to be
observed more than once to measure consistency between runs.  Any Moon
phase is ok.

INSTRUMENT: SurveyCam

FILTERS: ugriz

COMMENTS: (none)

BRIEF SCIENCE JUSTIFICATION:  (restrict yourself to 1-2 paragraphs)

As part of the PI's thesis, we wish to gather high-quality ugriz
photometry of G and K stars within 25 pc.  These data will be part of
a comprehensive search for substellar companions and circumstellar
disks around roughly 1800 G, K and M type stars within 25 pc.  The
optical data from this program are needed to evaluate the spectral
energy distributions (SEDs) of the stars, and will be used in tandem
with 2MASS and WISE photometry to extend the SEDs to near-infrared
wavelengths.  Surprisingly few members of the nearby star sample have
carefully calibrated, low-error measurements in the ugriz filters ---
the proposed observations will remedy this situation by providing
high-quality photometry for the fundamental sample of nearby stars.
The ARCSAT+SurveyCam combination is particularly suited to do this
work because the telescope's relatively small size allows us to
measure ugriz magnitudes for stars brighter than magnitude 10, and the
paucity of data is especially noticeable for the 700 local G and K
stars, for which larger class telescopes saturate.

In a 7-night run, we will target ~100 stars with magnitudes 6-16 to
map the parameter space of objects that can be effectively observed
with ARCSAT+SurveyCam and begin our survey of G, K and ultimately M
type stars in the solar neighborhood.  Stars will be observed twice
each to test repeatability.  Non-photometric conditions will be used
to measure magnitude differences in ugriz, and to check separations
and position angles of binaries, astrometry that is useful for the
RECONS 25 Parsec Database currently being built as part of our survey
of the solar neighborhood (www.recons.org).