We review the observed properties of exoplanets found by the Doppler
technique which has revealed 152 exoplanets to date. We focus on our ongoing
18-year survey of 1330 FGKM type stars at Lick, Keck, and the Anglo-Australian
Telescopes carried out with a uniform Doppler precision of 3 m/s. The 104
planets detected in our survey have masses as low as 15 M_Earth orbiting
between 0.03 and 5.5 AU. The mass distribution rises toward the lowest
detectable masses as dN/dM is proportional to M^-1.1. Nearly all giant planets
orbiting within 2 AU of all FGK stars within 30 pc have now been discovered.
The distribution of semi-major axes rises from 0.3 -- 3.0 AU (in bins of Delta
log a), but remains unknown for larger orbits. Extrapolation suggests that 12%
of the FGK stars harbor exoplanets within 20 AU. The median orbital
eccentricity is <e>=0.25 (excluding those tidally circularized), lower than
previously measured . Planets orbiting beyond 3 AU continue to exhibit non-zero
eccentricity, suggesting that the circular orbits of giant planets in our Solar
System are unusual. The occurrence rate of ``hot Jupiters'' within 0.1 AU is
1.2$\pm$0.3 %. The probability of occurrence of planets varies as the square of
the stellar metal abundance, $P \propto N^2_Fe, ranging from $<$3% for stars of
subsolar metallicity to 25% for stars with [Fe/H] > +0.3. Nearly 14% of
planet-bearing stars harbor multiple-planet systems, occasionally locked in
resonances. Kepler and Corot should measure the occurrence of earth-sized
planets. The Space Interferometry Mission (SIM) will detect planets with masses
as low as 3 M_ Earth orbiting within 2 AU of nearby stars and will measure
masses, orbits and multiplicity. These candidate rocky planets will motivate
spectroscopic follow-up by the ``Terrestrial Planet Finder'' and Darwin.}
References and citations for this submission: SLAC-SPIRES HEP (refers to ,
cited by, arXiv reformatted); CiteBase (autonomous citation navigation and analysis)
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