137 citations · 2.2k across the 56 of their papers we have counts for
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Cluster Difference Imaging Photometric Survey. I. Light Curves of Stars in Open Clusters from TESS Sectors 6 & 7
L. G. Bouma, J. D. Hartman, W. Bhatti +2
The Transiting Exoplanet Survey Satellite (TESS) is providing precise time-series photometry for most star clusters in the solar neighborhood. Using the TESS images, we have begun…
A Search for Variable Stars in the Globular Cluster M4 with K2
Joshua J. Wallace, Joel D. Hartman, Gaspar A. Bakos +1
We extract light curves for 4554 objects with in the K2 superstamp observations of the globular cluster M4, including 3784 cluster members, and search for variability. Amo…
Ultralow-amplitude RR Lyrae Stars in M4
Joshua J. Wallace, Joel D. Hartman, Gaspar A. Bakos +1
We report evidence for a new class of variable star, which we dub millimagnitude RR Lyrae (mmRR). From K2 observations of the globular cluster M4, we find that out of 24 horizontal…
Eclipsing Spotted Giant Star With K2 and Historical Photometry
K. Oláh, S. Rappaport, T. Borkovits +15
Context. Stars can maintain their observable magnetic activity from the PMS to the tip of the red giant branch. However, the number of known active giants is much lower than active…
A 0.24+0.18 Msun double-lined eclipsing binary from the HATSouth survey
G. Zhou, D. Bayliss, J. D. Hartman +21
We report the discovery and characterisation of a new M-dwarf binary, with component masses and radii of M1 = 0.244 -0.003/+0.003 Msun, R1 = 0.261 -0.009/+0.006 Rsun, M2 = 0.179 -0…
Stellar rotational periods in the planet hosting open cluster Praesepe
Geza Kovacs, Joel D. Hartman, Gaspar A. Bakos +6
By using the dense coverage of the extrasolar planet survey project HATNet, we Fourier analyze 381 high-probability members of the nearby open cluster Praesepe (Beehive/M44/NGC 263…
Direct Confirmation of the Asymmetry of the Cas A Supernova with Light Echoes
A. Rest, R. J. Foley, B. Sinnott +21
We report the first detection of asymmetry in a supernova (SN) photosphere based on SN light echo (LE) spectra of Cas A from the different perspectives of dust concentrations on it…
Variable Point Sources in Sloan Digital Sky Survey Stripe 82. I. Project Description and Initial Catalog (0 h < R.A. < 4 h)
Waqas A. Bhatti, Michael W. Richmond, Holland C. Ford +1
We report the first results of a study of variable point sources identified using multi-color time-series photometry from Sloan Digital Sky Survey (SDSS) Stripe 82 over a span of n…