# Summary of K2 Program GO13014

Title: Rotation rates and ages of stars in wide binary systems, and a search for hierarchical triples in Kepler K2 campaigns 11-12-13

PI: Lepine, Sebastien (Georgia State University)
CoIs: 

Wide binary systems are of high interest for both stellar astrophysics and exoplanet research. Because they were born and ejected from the same parent star cluster, they also share the same age and presumably have very similar chemical compositions. At the same time, their large separations mean that they essentially behave like single stars, and can also be observed and studied separately. For stellar astrophysics, these systems represent a unique means of testing stellar evolution models at moderate to old ages (2-12 Gy), complementing data available for younger ages from the study of nearby star clusters or young moving groups. In particular, old wide systems are critical to test the predictions of gyrochronology, which posit a relationship between the age of a low-mass star and its rotation rate, a relationship that may prove critical for dating exoplanet systems discovered by Kepler and other surveys. This gyrochronology hypothesis can be tested by measuring the rotation rates of stars in wide pairs, and verifying that the rotation rates are correlated, which should be true regardless of what their actual ages are. Based on a search of the SUPERBLINK proper motion catalog in the fields to be observed in K2 campaigns 11, 12, and 13, we have identified a total of 180 common proper motion (i.e. co-moving) pairs of stars with angular separations between 4 and 60. Our statistical analysis indicates that about 90% of those pairs must be physical binaries in wide orbits (with the rest being chance alignment of unrelated stars). Half the primaries in those wide systems appear to be main-sequence stars of subtypes F-G-K, with the other half consisting of M dwarfs. A majority of the secondaries, on the other hand, appear to be main-sequence M dwarfs. We propose to use Kepler to observe there stars in wide binary pairs, and measure their rotation rates from an auto-correlation analysis of their light curves. All the pairs should be resolved on the Kepler cameras (4 arcsec pixel size), although some pairs will have overlapping point spread functions and may require pixel-by-pixel analysis. Interestingly, many pairs can be observed in a single Kepler aperture, and thus may only need to be counted as a single target (or may use fewer pixels overall). One prediction of stellar multiplicity models is that very wide companions are often produced by dynamical relaxation in a triple systems, which means that a significant fraction of wide binaries may actually be hierarchical triples, with the inner system having a high probability of being a very tight (spectroscopic or eclipsing) binary star; this prediction will be directly tested with K2, by measuring the detection rate of eclipsing binaries in those pairs.

# Targets requested by this program that have been observed (92)
EPIC ID, RA (J2000) [deg], Dec (J2000) [deg], magnitude, Investigation IDs
210526118, 67.432691, 15.840519, 11.664, GO13014_LC|GO13049_LC|GO13071_LC|GO13122_LC|GO13002_LC
210526155, 67.433854, 15.84101, 12.274, GO13014_LC|GO13018_LC
210530576, 67.218881, 15.911506, 17.93, GO13014_LC|GO13015_LC
210530997, 67.23168, 15.918232, 17.531, GO13014_LC
210531078, 67.246877, 15.919571, 15.845, GO13014_LC|GO13018_LC
210750447, 66.752503, 19.115766, 9.361, GO13014_LC|GO13071_LC|GO13122_LC|GO13019_LC|GO13902_LC|GO13904_LC
210750573, 66.752588, 19.117648, 7.806, GO13014_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13036_LC|GO13039_LC|GO13019_LC|GO13902_LC|GO13904_LC
210754849, 66.646909, 19.184052, 18.282, GO13014_LC|GO13015_LC|GO13902_LC|GO13904_LC
210755553, 66.647622, 19.194291, 14.859, GO13014_LC|GO13049_LC|GO13002_LC|GO13006_LC|GO13036_LC|GO13015_LC|GO13902_LC|GO13904_LC
210870227, 65.172158, 20.932711, 11.78, GO13014_LC|GO13049_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13050_LC
210870601, 65.172735, 20.938549, 14.811, GO13014_LC|GO13018_LC
210915310, 65.30949, 21.630185, 14.95, GO13008_LC|GO13014_LC|GO13018_LC|GO13006_LC
210915987, 65.316143, 21.640549, 14.601, GO13014_LC|GO13049_LC|GO13018_LC|GO13002_LC|GO13006_LC|GO13036_LC|GO13050_LC
210927142, 66.539774, 21.819712, 15.342, GO13014_LC|GO13018_LC
210927181, 66.543487, 21.820353, 15.888, GO13014_LC|GO13018_LC
246708878, 70.949513, 14.684535, 11.023, GO13014_LC|GO13049_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13006_LC
246709862, 70.946469, 14.695929, 14.989, GO13014_LC|GO13018_LC|GO13006_LC
246715852, 72.541938, 14.769557, 12.449, GO13014_LC|GO13049_LC|GO13071_LC|GO13122_LC|GO13002_LC
246715859, 72.543016, 14.769627, 15.358, GO13014_LC|GO13018_LC
246720573, 74.952487, 14.827907, 13.112, GO13014_LC|GO13002_LC
246720644, 74.952427, 14.828899, 11.688, GO13014_LC|GO13049_LC|GO13071_LC|GO13122_LC|GO13036_LC
246721581, 74.949665, 14.839914, 18.309, GO13014_LC
246725886, 73.070095, 14.893139, 16.035, GO13014_LC|GO13015_LC
246725909, 73.073978, 14.893375, 15.482, GO13014_LC|GO13002_LC|GO13015_LC
246778946, 74.262223, 15.511695, 16.219, GO13014_LC|GO13018_LC
246779014, 74.26099, 15.51236, 15.715, GO13014_LC|GO13018_LC|GO13015_LC
246787361, 75.009117, 15.603732, 13.395, GO13014_LC|GO13049_LC|GO13018_LC|GO13122_LC|GO13002_LC
246787379, 75.007731, 15.60391, 15.708, GO13014_LC|GO13018_LC
246797731, 74.422027, 15.717828, 16.797, GO13014_LC
246797852, 74.420699, 15.719273, 14.49, GO13014_LC|GO13123_LC|GO13018_LC
246845715, 74.896546, 16.217756, 16.071, GO13014_LC|GO13018_LC
246906998, 76.75968, 16.820468, 10.096, GO13014_LC|GO13071_LC|GO13122_LC|GO13039_LC|GO13903_LC
246907677, 76.755968, 16.82742, 8.778, GO13014_LC|GO13012_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13024_LC|GO13039_LC|GO13052_LC|GO13903_LC|GO13012_SC
246909272, 77.539582, 16.842588, 11.26, GO13014_LC|GO13123_LC|GO13071_LC|GO13122_LC|GO13024_LC
246909566, 77.523604, 16.845444, 17.231, GO13014_LC
246977598, 70.702377, 17.506832, 13.069, GO13014_LC|GO13049_LC|GO13123_LC|GO13018_LC|GO13122_LC|GO13002_LC|GO13006_LC
246978205, 70.711483, 17.512482, 15.432, GO13014_LC|GO13018_LC|GO13006_LC
247029659, 74.132513, 17.999869, 13.797, GO13014_LC|GO13049_LC|GO13123_LC|GO13018_LC|GO13006_LC
247029935, 74.122723, 18.002377, 8.941, GO13014_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13006_LC|GO13065_LC|GO13903_LC
247048461, 75.067975, 18.180191, 13.548, GO13014_LC
247048513, 75.063037, 18.18071, 13.407, GO13014_LC|GO13018_LC|GO13002_LC
247064866, 74.202922, 18.335321, 15.744, GO13014_LC|GO13018_LC|GO13006_LC
247065446, 74.200626, 18.340702, 13.905, GO13014_LC|GO13123_LC|GO13018_LC|GO13002_LC|GO13006_LC
247082144, 73.689069, 18.497293, 14.923, GO13014_LC|GO13018_LC|GO13006_LC
247082590, 73.68724, 18.501347, 14.706, GO13014_LC|GO13018_LC|GO13002_LC|GO13006_LC|GO13036_LC
247160111, 69.391221, 19.24379, 11.373, GO13014_LC|GO13049_LC|GO13071_LC|GO13122_LC|GO13002_LC
247160262, 69.385366, 19.245131, 15.75, GO13014_LC|GO13018_LC
247227231, 78.570839, 19.88295, 9.087, GO13014_LC|GO13049_LC|GO13123_LC|GO13071_LC|GO13122_LC|GO13032_LC|GO13002_LC|GO13062_LC|GO13024_LC|GO13039_LC|GO13903_LC
247227517, 78.571842, 19.885357, 15.079, GO13014_LC
247239640, 73.174782, 19.999526, 9.538, GO13008_LC|GO13014_LC|GO13071_LC
247239752, 73.175027, 20.000611, 9.276, GO13008_LC|GO13014_LC|GO13071_LC|GO13002_LC|GO13023_LC|GO13098_LC|GO13024_LC|GO13039_LC|GO13903_LC
247245324, 80.424949, 20.052317, 15.281, GO13014_LC
247245507, 80.425106, 20.05407, 12.242, GO13014_LC|GO13049_LC|GO13123_LC|GO13071_LC|GO13018_LC|GO13122_LC
247253678, 79.381343, 20.129477, 9.499, GO13014_LC|GO13071_LC|GO13122_LC|GO13019_LC
247253928, 79.379805, 20.131841, 6.699, GO13014_LC|GO13097_LC|GO13122_LC|GO13002_LC|GO13024_LC|GO13036_LC|GO13039_LC|GO13019_LC|GO13903_LC|GO13097_SC
247362858, 76.921887, 21.093388, 16.516, GO13014_LC
247363137, 76.922826, 21.095534, 13.69, GO13014_LC|GO13049_LC|GO13018_LC
247388710, 75.673596, 21.305036, 14.025, GO13014_LC|GO13018_LC
247388925, 75.672764, 21.306731, 11.876, GO13014_LC|GO13049_LC|GO13123_LC|GO13071_LC|GO13122_LC
247449245, 69.726912, 21.79681, 15.02, GO13014_LC|GO13018_LC
247449449, 69.723141, 21.798452, 12.358, GO13014_LC|GO13049_LC|GO13010_LC|GO13071_LC|GO13002_LC|GO13050_LC
247532545, 70.784859, 22.444189, 15.008, GO13014_LC|GO13049_LC|GO13018_LC|GO13015_LC|GO13050_LC
247533036, 70.787108, 22.448177, 18.898, GO13014_LC|GO13015_LC
247570791, 68.249116, 22.739872, 17.895, GO13014_LC|GO13002_LC|GO13015_LC
247570800, 68.247717, 22.739907, 14.686, GO13014_LC|GO13018_LC
247649755, 70.717382, 23.339569, 13.837, GO13008_LC|GO13014_LC|GO13064_LC|GO13123_LC|GO13018_LC|GO13023_LC|GO13077_LC|GO13073_LC|GO13090_LC
247650112, 70.73297, 23.342112, 16.94, GO13014_LC
247773801, 70.432387, 24.22753, 15.512, GO13014_LC|GO13018_LC|GO13006_LC
247774168, 70.433527, 24.229977, 18.931, GO13014_LC
247895273, 68.312907, 25.060291, 18.389, GO13014_LC|GO13002_LC|GO13015_LC
247895479, 68.313021, 25.061703, 19.04, GO13014_LC|GO13015_LC
247898972, 75.476652, 25.086011, 14.767, GO13014_LC|GO13049_LC|GO13018_LC|GO13002_LC
247899123, 75.476382, 25.0871, 15.515, GO13014_LC|GO13015_LC
247905449, 75.081382, 25.130827, 11.878, GO13014_LC|GO13049_LC|GO13010_LC|GO13123_LC|GO13018_LC
247906277, 75.073011, 25.136441, 8.439, GO13014_LC|GO13012_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13024_LC|GO13039_LC|GO13903_LC|GO13012_SC
247969163, 69.912665, 25.580357, 18.065, GO13014_LC
247969715, 69.906265, 25.584415, 17.959, GO13014_LC
247992384, 66.2951, 25.749177, 8.582, GO13014_LC|GO13012_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13006_LC|GO13024_LC|GO13039_LC|GO13052_LC|GO13903_LC|GO13012_SC
247992416, 66.281884, 25.749409, 13.579, GO13014_LC|GO13018_LC|GO13006_LC
248019492, 70.855107, 25.950326, 11.614, GO13014_LC|GO13002_LC
248019700, 70.854967, 25.951734, 12.461, GO13117_LC|GO13014_LC|GO13071_LC
248036066, 68.550485, 26.074859, 14.708, GO13014_LC
248036338, 68.549859, 26.076956, 14.521, GO13014_LC|GO13018_LC
248084889, 68.145897, 26.460223, 13.429, GO13014_LC|GO13049_LC
248085018, 68.141078, 26.461106, 10.36, GO13014_LC|GO13049_LC|GO13071_LC|GO13122_LC|GO13002_LC|GO13024_LC|GO13052_LC
248140977, 69.622981, 26.939256, 7.167, GO13014_LC|GO13122_LC|GO13002_LC|GO13024_LC|GO13039_LC|GO13019_LC
248141116, 69.623231, 26.940436, 7.331, GO13014_LC|GO13071_LC|GO13122_LC|GO13019_LC
248285301, 73.678908, 28.371193, 16.651, GO13014_LC
248285357, 73.679978, 28.371908, 14.752, GO13014_LC|GO13018_LC
251456954, , , , GO13014_LC
251456955, , , , GO13014_LC|GO13015_LC
251456956, , , , GO13014_LC