Okayama Planet Search Program

Okayama Planet Search Program is started 2001, spectroscopically searching for planetary systems around stars, report on the detection of 3 new extrasolar planets (18 Delphini b, Xi Aquilae|Xi Aql b, HD 81688b) around intermediate-mass G and K giants (18 Delphini, Xi Aql, HD 81688). Also update the orbital parameters of HD 104985 b, the first planet discovered around G giants from our survey, by using the data collected during the past six years. Since 2001, has been conducting a precise Doppler survey of about 300 G and K giants using a 1.88m telescope, the HIgh Dispersion Echelle Spectrograph (HIDES), and an iodine absorption cell (I2 cell - the internal statistical error can be very small.) at Okayama Astrophysical Observatory (OAO), for precise radial velocity measurements. Use of numerical calculations suggest that Jupiter-mass planets within about (distance range) ^+0.5
_−0.25 AU in fuction of the metallicity and adopted models).