The Kepler Mission is in the development phase with launch planned for 2008. The mission goal is ... more The Kepler Mission is in the development phase with launch planned for 2008. The mission goal is to reliably detect a significant number of Earth-size and smaller planets in the habitable zone of solar-like stars. (see W. Borucki, et al, this meeting.) The mission design allows for exploring the diversity of planetary sizes and orbital periods for a wide variety
We present a refined analysis of 15,038 Kepler main sequence light curves to determine the stella... more We present a refined analysis of 15,038 Kepler main sequence light curves to determine the stellar rotation periods. The initial period estimates come from an autocorrelation function, as has been done before. We then measure the duration of every intensity dip in the light curve, expressed as fractions of the initial rotation period estimate. These dip duration distributions are subdivided into several regions whose relation to each other helps determine which harmonic of the initial rotation period is most physically plausible. We compare our final rotation periods to those from McQuillan et al. (2014) and find that the great majority agree, but about 10% of their periods are doubtful (usually twice as long as is most plausible). We are still refining our method, and will later extend it to more stars to substantially increase the sample of reliable stellar rotation periods.
The IUE data on 36 late type close binary stars are presented. It is shown that the chromospheric... more The IUE data on 36 late type close binary stars are presented. It is shown that the chromospheric and TR line fluxes increase with decreasing stellar rotation period, though not as rapidly as does the X-ray flux. There is an increasing dependence upon rotation with increasing line temperature. The data are consistent with the hypothesis that there exists a critical rotation rate, which depends on temperature, below which the emission flux is independent of rotation and above which it increases linearly with increasing angular velocity omega.
The Kepler Mission is in the development phase with launch planned for 2008. The mission goal is ... more The Kepler Mission is in the development phase with launch planned for 2008. The mission goal is to reliably detect a significant number of Earth-size and smaller planets in the habitable zone of solar-like stars. (see W. Borucki, et al, this meeting.) The mission design allows for exploring the diversity of planetary sizes and orbital periods for a wide variety
We present a refined analysis of 15,038 Kepler main sequence light curves to determine the stella... more We present a refined analysis of 15,038 Kepler main sequence light curves to determine the stellar rotation periods. The initial period estimates come from an autocorrelation function, as has been done before. We then measure the duration of every intensity dip in the light curve, expressed as fractions of the initial rotation period estimate. These dip duration distributions are subdivided into several regions whose relation to each other helps determine which harmonic of the initial rotation period is most physically plausible. We compare our final rotation periods to those from McQuillan et al. (2014) and find that the great majority agree, but about 10% of their periods are doubtful (usually twice as long as is most plausible). We are still refining our method, and will later extend it to more stars to substantially increase the sample of reliable stellar rotation periods.
The IUE data on 36 late type close binary stars are presented. It is shown that the chromospheric... more The IUE data on 36 late type close binary stars are presented. It is shown that the chromospheric and TR line fluxes increase with decreasing stellar rotation period, though not as rapidly as does the X-ray flux. There is an increasing dependence upon rotation with increasing line temperature. The data are consistent with the hypothesis that there exists a critical rotation rate, which depends on temperature, below which the emission flux is independent of rotation and above which it increases linearly with increasing angular velocity omega.
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Papers by Gibor Basri