Identifying the Young Low-mass Stars within 25 pc. I. Spectroscopic Observations (2009)
Shkolnik, Evgenya, Liu, Michael C., Reid, I. Neill
We have completed a high-resolution (R=60,000) optical spectroscopic survey of 185 nearby M dwarfs identified using ROSAT data to select active, young objects with fractional X-ray luminosities...
2MASS 22344161+4041387AB: A Wide, Young, Accreting, Low-mass Binary in the LkHa233 Group (2009)
Allers, K. N., Liu, Michael C., Shkolnik, Evgenya, Cushing, Michael C., Dupuy, Trent J., Mathews, Geoffrey S., ...
We report the discovery of a young, 0.16" binary, 2M2234+4041AB, found as the result of a Keck laser guide star adaptive optics imaging survey of young field ultracool dwarfs. Spatially resolved...
Star-Planet Interactions (2008)
Shkolnik, Evgenya, Aigrain, Suzanne, Cranmer, Steven, Fares, Rim, Fridlund, Malcolm, Pont, Frederic, ...
Much effort has been invested in recent years, both observationally and theoretically, to understand the interacting processes taking place in planetary systems consisting of a hot Jupiter orbiting...
BD-22 5866: A Low-mass Quadruple-lined Spectroscopic AND Eclipsing Binary (2008)
Shkolnik, Evgenya, Liu, Michael C., Reid, I. Neill, Hebb, Leslie, Cameron, Andrew C., Torres, Carlos A., ...
We report our discovery of an extremely rare, low mass, quadruple-lined spectroscopic binary BD-22 5866 (=NLTT 53279, integrated spectral type = M0 V), found during an ongoing search for the youngest...
MOST detects variability on tau Bootis possibly induced by its planetary companion (2008)
Walker, Gordon A. H., Croll, Bryce, Matthews, Jaymie M., Kuschnig, Rainer, Huber, Daniel, Weiss, Werner W., ...
(abridged) There is considerable interest in the possible interaction between parent stars and giant planetary companions in 51 Peg-type systems. We demonstrate from MOST satellite photometry and Ca...
The On/Off Nature of Star-Planet Interactions (2007)
Shkolnik, Evgenya, Bohlender, David A., Walker, Gordon A. H., Cameron, Andrew Collier
Evidence suggesting an observable magnetic interaction between a star and its hot Jupiter appears as a cyclic variation of stellar activity synchronized to the planet's orbit. In this study, we...
No Detectable H3+ Emission from the Atmospheres of Hot Jupiters (2006)
Shkolnik, Evgenya, Gaidos, Eric, Moskovitz, Nick
H$_3^+$ emission is the dominant cooling mechanism in Jupiter's thermosphere and a useful probe of temperature and ion densities. The H$_3^+$ ion is predicted to form in the thermospheres of close-in...
Shkolnik, Evgenya, Walker, Gordon, Rucinski, Slavek, Bohlender, David, Davidge, Tim
The synchronously rotating G stars in the detached, short-period (0.7 d), partially eclipsing binary, ER Vul, are the most chromospherically active solar-type stars known. We have monitored activity...
Differential rotation of the active G5V star Kappa1 Ceti: Photometry from the MOST satellite (2004)
Rucinski, Slavek M., Walker, Gordon A. H., Matthews, Jaymie M., Kuschnig, Rainer, Shkolnik, Evgenya, Marchenko, Sergey, ...
About 30.5 days of nearly uninterrupted broadband photometry of the solar-type star Kappa1 Ceti, obtained with the MOST (Microvariability & Oscillations of STars) satellite, shows evidence for two...
Evidence for Planet-induced Chromospheric Activity on HD 179949 (2003)
Shkolnik, Evgenya, Walker, Gordon A. H., Bohlender, David A.
We have detected the synchronous enhancement of Ca II H & K emission with the short-period planetary orbit in HD 179949. High-resolution spectra taken on three observing runs extending more than a...
The Radial Velocity Precision of Fiber-fed Spectrographs (2003)
Walker, Gordon A. H., Shkolnik, Evgenya, Bohlender, David A., Yang, Stephenson
We have measured the radial velocities of five 51 Peg-type stars and one star with constant velocity. Our measurements, on 20 \AA centered at 3947 \AA, were conventional using Th/Ar comparison...
Modulation of Ca II H & K Emission by Short-Period Planets (2002)
Shkolnik, Evgenya, Walker, Gordon A. H., Bohlender, David A.
We have detected modulation of the Ca II H&K reversal structure in four out of five 51 Peg-type stars whose planets have orbital periods between 3 and 4 days. We observe two effects in the K-core:...