  The vast majority of known extrasolar planets orbit stars with a narrow range
of masses (0.7-1.3 M_sun). Recent years have seen rapid growth in our knowledge
about the properties of planetary systems with host stars significantly more
massive than the Sun. Planet formation models predict that giant planets are
more common around higher-mass stars (M>1.5M_sun). However, these types of
stars pose severe observational challenges while on the main sequence,
resulting in a strong bias against them in current planet searches.
Fortunately, it is possible to obtain high-precision Doppler velocities for
these massive stars as they evolve off the main sequence and cool as subgiants.
We describe the Pan-Pacific Planet Search, a survey of 170 subgiant stars using
the 3.9m Australian Astronomical Telescope. In collaboration with J. Johnson's
Keck survey of Northern retired A stars, we are monitoring nearly every
subgiant brighter than V=8. This survey will provide critical statistics on the
frequency and characteristics of planetary systems formed around higher-mass
stars.
