ARCSAT ID NUMBER: AS07

DESCRIPTIVE TITLE: Time Domain Studies of Transients and Variable Stars

PI: Guy Stringfellow

OBSERVER(S): Guy Stringfellow, CU undergrads TBD

UNCERTIFIED/UNTRAINED OBSERVERS: CU undergrads

COLLABORATORS: 
 
CONTACT INFORMATION:  Guy.Stringfellow@colorado.edu   303-506-3160 cell

NUMBER OF WEEKS REQUESTED:  3

TIME REQUESTED: 
Requires Dark time and time cadence ~monthly
Run 1:    July 13 (alternate: July 6)
Run 2:    Aug 10 (alternate: August 10, then August 24)
Run 3:    Sept 7 or 14

INSTRUMENT: SurveyCam

FILTERS:  BVRI Ha

COMMENTS: 
Unavailable May 22-23, June 17-26,  July 3 (observing plus conference)
Amenable to partial week blocks more frequently if others also request this,
so long as our targets are observable. This applies particularly to the week
of June 8 when we could use the 2nd half of the night for our program (the 
2nd half of June conflicts with other observing programs).

BRIEF SCIENCE JUSTIFICATION: 
Several types of eruptive or variable stars are being studied. These include accretion driven
outbursts from young stellar objects (YSOs), more modest accretion variability of YSOs, 
novae, Luminous Blue Variable stars and the related supernovae impostors. The discovery and 
light curves of recent novae in M31 have been followed in previous ARCSAT runs (e.g., see
AstroTel#6324 where we confirm M31 Nova 2014-07a and report pre-discovery photometry 
extending over a 5 day period), and M31 remains a priority target. Based on our previous ARCSAT observations, we now have an 11-tile grid covering M31. It takes about 2-3 nights to cover this grid 
in 4 filters with 3x300s exposures in each filter for each tile with an 8 hour observing window each 
night. To both follow identified transients as well as discover new ones, repeated observations of the 
same fields are required, so select tiles are revisited as frequently as once a night during the runs. 
M31 is a 2nd half of the night target in July-August, becoming visible most of the night in September. 
Two summer star forming regions are also priority targets during the summer months: Ophiuchus and 
the Pelican/North American regions. Ophiuchus is up (below 2 airmass) for several hours at the start 
of the night during July-August, while the Pelican rises at 10PM at the start of July and remains up all 
night through the summer. M101 and M51 fill in the first part of the night. [We note that Ophiuchus 
and M31 are second half of the night targets during May, with Oph transitioning to a 1st half night 
target during June]. As we are pushing ARCSAT down to below 18 mag, dark time (or when the Moon 
is at low declination away from our targets) is required, and the dates selected reflect this constraint. 
This science program is being used to introduce select CU undergrads to observational research methods 
and practices, including observing, data reduction, and aspects of analysis.