INSTITUTIONAL ID NUMBER: AS01

DESCRIPTIVE TITLE: Characterization of K dwarf eclipsing binary in Kepler field

PI: Brett Morris, Krzysztof Suberlak, Olivia Telford

OBSERVER(S): Brett Morris, Krzysztof Suberlak

UNCERTIFIED/UNTRAINED OBSERVERS: None

COLLABORATORS: Leslie Hebb, James Davenport, Suzanne Hawley
 
CONTACT INFORMATION: 
Brett Morris, bmmorris@uw.edu
Krzysztof Suberlak, suberlak@uw.edu
Olivia Telford, otelford@uw.edu

TIME REQUESTED:
We are observing an eclipsing binary during eclipse events, so our times are
fixed by the ephemeris of the binary. There are four eclipse events that we can
observe with ARCSAT, and we would like to observe two of them. The eclipse events
this quarter, occurring at 5 day intervals, do not match up with the 
Monday-Sunday phasing of the observing allocation blocks for ARCSAT. The eclipse
dates are 10/23, 10/28, 11/02 and 11/07 UT (which we'll refer to as eclipses 1-4). 

Therefore there are several combinations of weeks that can produce two eclipse
observations. We list the potential combinations in order of preference:
Option 1: 10/27-11/02 and 11/03-11/09 Mountain time
(containing eclipses 2, 3, 4)

Option 2: 10/27-11/02 Mountain time
(containing eclipses 2, 3)

Option 3: 10/20-10/26 and 10/27-11/02 Mountain time
(containing eclipses 1, 2, 3)



INSTRUMENT: FlareCam

Filters: g, r, i

BRIEF SCIENCE JUSTIFICATION:  

Accurate measurements of stellar radii, masses, and effective temperatures are 
essential for tests of theories of stellar evolution. Eclipsing binaries (EBs) 
are ideal laboratories for obtaining these measurements. The Kepler program has 
detected a plethora (>2600) of EBs, roughly 100 of which have been followed up 
and for which reliable masses, radii, and spectral types have been obtained 
(Torres et al. 2010). However, there remains a paucity of measurements for low 
mass stars (K and M dwarfs). To improve constraints on theories of stellar 
evolution at the low-mass end, we have proposed to use ARCES and DIS (in 
high-resolution mode) at APO to obtain radial velocity measurements and 
metallicities for an EB system in the Kepler field containing two K dwarfs. We 
will further use a low-resolution DIS spectrum to obtain a flux calibration 
and determination of the spectral type. With ARCSAT, we will collect multi-band
photometry in the visible to measure the variation in eclipse depths with 
wavelength to constrain the temperature ratio and radius ratio of the binary 
components, and to update the eclipse ephemeris.

REFERENCES: 
Torres, G., Andersen, J., & Gimenez, A. 2010, AAPR, 18, 67