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Full-Text Articles in Physics
Precise Radial Velocities Of Giant Stars. Ii. Pollux And Its Planetary Companion, Sabine Reffert, Andreas Quirrenbach, David Mitchell, Simon Albrecht, Saskia Hekker, Debra A. Fischer, Geoffrey W. Marcy, R. Paul Butler
Precise Radial Velocities Of Giant Stars. Ii. Pollux And Its Planetary Companion, Sabine Reffert, Andreas Quirrenbach, David Mitchell, Simon Albrecht, Saskia Hekker, Debra A. Fischer, Geoffrey W. Marcy, R. Paul Butler
Debra A Fischer
It has long been speculated that the observed periodic radial velocity pattern for the K giant Pollux might be explained in terms of an orbiting planetary companion. We have collected 80 high-resolution spectra for Pollux at Lick Observatory yielding precise radial velocities with a mean error of 3.8 m s-1, providing the most comprehensive and precise data set available for this star. Our data confirm the periodicity previously seen in the radial velocities. We derive a period of 589.7 ± 3.5 days and, assuming a primary mass of 1.86 M, a minimum companion mass of 2.9 ± 0.3MJup, consistent with …
Discovery Of A Substellar Companion To The K2 Iii Giant Ɩ Draconis, Sabine Frink, David Mitchell, Andreas Quirrenbach, Debra A. Fischer, Geoffrey W. Marcy, R. Paul Butler
Discovery Of A Substellar Companion To The K2 Iii Giant Ɩ Draconis, Sabine Frink, David Mitchell, Andreas Quirrenbach, Debra A. Fischer, Geoffrey W. Marcy, R. Paul Butler
Debra A Fischer
We report precise radial velocity measurements of the K giant ɩ Dra (HD 137759, HR 5744, HIP 75458), carried out at Lick Observatory, which reveal the presence of a substellar companion orbiting the primary star. A Keplerian fit to the data yields an orbital period of about 536 days and an eccentricity of 0.70. Assuming a mass of 1.05 M8 for ɩ Dra, the mass function implies a minimum companion mass m2 sin i of 8.9 MJ, making it a planet candidate. The corresponding semimajor axis is 1.3 AU. The nondetection of the orbital motion by Hipparcos …