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Full-Text Articles in Physical Sciences and Mathematics
Spectroscopy And Photometry Of Nearby Young Solar Analogs, Eric J. Gaidos, Gregory W. Henry, Stephen M. Henry
Spectroscopy And Photometry Of Nearby Young Solar Analogs, Eric J. Gaidos, Gregory W. Henry, Stephen M. Henry
Information Systems and Engineering Management Research Publications
We present new photometry and spectroscopy of 34 stars from a catalog of 38 nearby (d < 25 pc) G and K dwarfs selected as analogs to the early Sun. We report that the least active star in our sample is also slowly rotating and probably of solar age. Two other stars appear to be evolved objects that have recently acquired angular momentum. A fourth star may be a spectroscopic binary. Many of the other stars belong to previously identified common proper-motion groups. Space motions, lithium abundances, and Ca II emission of these stars suggest ages between 70 and 800 Myr.
Search For Transits Of A Short-Period, Sub-Saturn Extrasolar Planet Orbiting Hd 46375, Gregory W. Henry
Search For Transits Of A Short-Period, Sub-Saturn Extrasolar Planet Orbiting Hd 46375, Gregory W. Henry
Information Systems and Engineering Management Research Publications
Precise brightness measurements of HD 46375 have been acquired with an automatic telescope to search for transits of its short-period, sub-Saturn extrasolar planet. Transits of the companion do not occur, indicating that the inclination of the orbit i is less than 83° and sin i is less than 0.992. This upper limit on sin i still preserves the possibility that the mass of the planet is less than Saturn's. Analysis of the photometry for HD 46375 reveals no photometric variability larger than 0.0001 ± 0.0002 mag at the orbital period of the planet. This effectively eliminates starspots and stellar pulsations …
Photometric And Ca Ii H And K Spectroscopic Variations In Nearby Sun-Like Stars With Planets. Iii., Gregory W. Henry, Sallie L. Baliunas, Robert A. Donahue, Francis C. Fekel, Willie Soon
Photometric And Ca Ii H And K Spectroscopic Variations In Nearby Sun-Like Stars With Planets. Iii., Gregory W. Henry, Sallie L. Baliunas, Robert A. Donahue, Francis C. Fekel, Willie Soon
Information Systems and Engineering Management Research Publications
We present the results of an analysis of time-series photometry, Ca II H and K spectrophotometry, and high-dispersion visible spectra of nine nearby Sun-like stars recently identified as having planets. For the six stars whose presumed planets have orbital periods of less than 4 months (τ Boo, 51 Peg, υ And, ρ1 Cnc, ρ CrB, and 70 Vir), sine-curve fits to the photometric data show no variations with semiamplitude greater than 1 or 2 parts in 104. Photometric variations in 47 UMa are similarly small, although our photometric data of this star are slightly affected by variability …
Planetary Companions To The Metal-Rich Stars Bd -10°3166 And Hd 52265, R. Paul Butler, Steve Vogt, Geoffrey W. Marcy, Debra A. Fischer, Gregory W. Henry, Kevin Apps
Planetary Companions To The Metal-Rich Stars Bd -10°3166 And Hd 52265, R. Paul Butler, Steve Vogt, Geoffrey W. Marcy, Debra A. Fischer, Gregory W. Henry, Kevin Apps
Information Systems and Engineering Management Research Publications
Precise Doppler measurements from the Keck/HIRES spectrometer reveal periodic Keplerian velocity variations in the stars BD -10°3166 and HD 52265. BD -10°3166 (K0 V) has a period of 3.487 days and a semiamplitude of 61 m s-1. An orbital fit yields a companion mass M sin i = 0.48 MJUP, a semimajor axis of a = 0.046 AU, and an eccentricity of e = 0.05 (consistent with zero). HD 52265 (G0 V) has a period of 119.0 days, a semiamplitude of 45 m s-1, an eccentricity of 0.29, a semimajor axis of a = …