Collisional Stripping and Disruption of Super-Earths (2009)
Marcus, Robert A., Stewart, Sarah T., Sasselov, Dimitar, Hernquist, Lars
The final stage of planet formation is dominated by collisions between planetary embryos. The dynamics of this stage determine the orbital configuration and the mass and composition of planets in the...
Direct Calculation of the Turbulent Dissipation Efficiency in Anelastic Convection (2008)
Penev, Kaloyan, Barranco, Joseph, Sasselov, Dimitar
The current understanding of the turbulent dissipation in stellar convective zones is based on the assumption that the turbulence follows Kolmogorov scaling. This assumption is valid for some cases...
Dissipation Efficiency in Turbulent Convective Zones in Low Mass Stars (2008)
Penev, Kaloyan, Sasselov, Dimitar, Robinson, Frank, Demarque, Pierre
We extend the analysis of Penev et al. (2007) to calculate effective viscosities for the surface convective zones of three main sequence stars of 0.775Msun, 0.85Msun and the present day Sun. In...
First Results From New 3D Spectral Simulations Of Anelastic Turbulent Convection (2008)
Penev, Kaloyan, Barranco, Joseph, Sasselov, Dimitar
We have adapted the anelastic spectral code of Barranco & Marcus (2006) to simulate a turbulent convective layer with the intention of studying the effectiveness of turbulent eddies in dissipating...
Photometric variability of the T Tauri star TW Hya on time scales of hours to years (2008)
Rucinski, Slavek M., Matthews, Jaymie M., Kuschnig, Rainer, Pojmański, Grzegorz, Rowe, Jason, Guenther, David B., ...
MOST (Microvariability & Oscillations of STars) and ASAS (All Sky Automated Survey) observations have been used to characterize photometric variability of TW Hya on time scales from a fraction of a...
Pribulla, Theodor, Rucinski, Slavek, Matthews, Jaymie M., Kuschnig, Rainer, Rowe, Jason F., Guenther, David B., ...
We present two series of MOST (Microvariability & Oscillations of STars) space-based photometry, covering nearly continuously 10 days in 2004 and 30 days in 2007, of selected variable stars in the...
Rowe, Jason F., Matthews, Jaymie M., Seager, Sara, Sasselov, Dimitar, Kuschnig, Rainer, Guenther, David B., ...
The Canadian MOST satellite is a unique platform for observations of bright transiting exoplanetary systems. Providing nearly continuous photometric observations for up to 8 weeks, MOST can produce...
Direct Detection of the Close Companion of Polaris with the Hubble Space Telescope (2008)
Evans, Nancy Remage, Schaefer, Gail H., Bond, Howard E., Bono, Giuseppe, Karovska, Margarita, Nelan, Edmund, ...
Polaris, the nearest and brightest classical Cepheid, is a single-lined spectroscopic binary with an orbital period of 30 years. Using the High Resolution Channel of the Advanced Camera for Surveys...
Li, Chih-Hao, Benedick, Andrew J., Fendel, Peter, Glenday, Alexander G., Kaertner, Franz X., Phillips, David F., ...
Searches for extrasolar planets using the periodic Doppler shift of stellar spectral lines have recently achieved a precision of 60 cm/s (ref 1), which is sufficient to find a 5-Earth-mass planet in...
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 Very Low Albedo of an Extrasolar Planet: MOST Spacebased Photometry of HD 209458 (2007)
Rowe, Jason F., Matthews, Jaymie M., Seager, Sara, Miller-Ricci, Eliza, Sasselov, Dimitar, Kuschnig, Rainer, ...
Measuring the albedo of an extrasolar planet provides insights into its atmospheric composition and its global thermal properties, including heat dissipation and weather patterns. Such a measurement...
Croll, Bryce, Matthews, Jaymie M., Rowe, Jason F., Gladman, Brett, Miller-Ricci, Eliza, Sasselov, Dimitar, ...
We have made a comprehensive transit search for exoplanets down to ~1.5 - 2 Earth radii in the HD 189733 system, based on 21-days of nearly uninterrupted broadband optical photometry obtained with...
Kaminski, Krzysztof Z., Rucinski, Slavek M., Matthews, Jaymie M., Kuschnig, Rainer, Rowe, Jason F., Guenther, David B., ...
The Hyades K2V+WD system 471 Tau is a prototype post-common envelope system and a likely cataclysmic binary progenitor. We present 10 days of nearly continuous optical photometry by the MOST...
Rucinski, Slavek, Kuschnig, Rainer, Matthews, Jaymie M., Dimitrov, Wojtek, Pribulla, Theodor, Guenther, David B., ...
The MOST photometric space mission discovered an eclipsing binary among its guide stars in June 2006 which combines a relatively large eccentricity e = 0.20 with an orbital period of only 2.27 days....
Gruberbauer, Michael, Kohlenberg, Katrien, Rowe, Jason F., Huber, Daniel, Matthews, Jaymie M., Reegen, Piet, ...
Highly precise and nearly uninterrupted optical photometry of the RR Lyrae star AQ Leo was obtained with the MOST (Microvariability & Oscillations of STars) satellite over 34.4 days in February-March...
The Differential Rotation of Kappa1 Ceti as Observed by MOST (2007)
Walker, Gordon A. H., Croll, Bryce, Kuschnig, Rainer, Walker, Andrew, Rucinski, Slavek M., Matthews, Jaymie M., ...
We first reported evidence for differential rotation of Kappa1 Ceti in Paper I. In this paper we demonstrate that the differential rotation pattern closely matches that for the Sun. This result is...
Croll, Bryce, Matthews, Jaymie M., Rowe, Jason F., Kuschnig, Rainer, Walker, Andrew, Gladman, Brett, ...
We have made a comprehensive transit search for exoplanets down to about 2 Earth radii in the HD 209458 system, based on nearly uninterrupted broadband optical photometry obtained with the MOST...
Polaris: Mass and Multiplicity (2006)
Evans, Nancy Remage, Schaefer, Gail, Bond, Howard E., Nelan, Edmund, Bono, Giuseppe, Karovska, Margarita, ...
Polaris, the nearest and brightest classical Cepheid, is a member of at least a triple system. It has a wide ($18''$) physical companion, the F-type dwarf Polaris B. Polaris itself is a single-lined...
On Dissipation inside Turbulent Convection Zones from 3D Simulations of Solar Convection (2006)
Penev, Kaloyan, Sasselov, Dimitar, Robinson, Frank, Demarque, Pierre
The development of 2D and 3D simulations of solar convection has lead to a picture of convection quite unlike the usually assumed Kolmogorov spectrum turbulent flow. We investigate the impact of this...
Cody, Ann Marie, Sasselov, Dimitar
Abundance analyses of stars with planets have revealed that their metallicities are enhanced relative to field stars. Such a trend was originally suggested to be due to accretion of iron-rich...
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...
Detecting Stellar Spots by Gravitational Microlensing (1999)
Heyrovsky, David, Sasselov, Dimitar
During microlensing events with a small impact parameter, the amplification of the source flux is sensitive to the surface brightness distribution of the source star. Such events provide a means for...
Probing Red Giant Atmospheres with Gravitational Microlensing (1999)
Heyrovsky, David, Sasselov, Dimitar, Loeb, Abraham
Gravitational microlensing provides a new technique for studying the surfaces of distant stars. Microlensing events are detected in real time and can be followed up with precision photometry and...
REMOVING DEGENERACY OF MICROLENSING LIGHT CURVES THROUGH NARROW-BAND PHOTOMETRY OF GIANTS (1995)
Loeb, Abraham, Sasselov, Dimitar
The standard light curve of a microlensing event provides only two constraints on the six unknown parameters of the lens. We show that narrow-band photometry during a microlensing event of a giant...