Detection and Characterization of Extrasolar Planets through Doppler Spectroscopy

Over 300 extrasolar planets have been found since 1992, showing that planetary systems are common and exhibit an outstanding variety of characteristics. As the number of detections grows and as models of planet formation progress to account for the existence of these new worlds, statistical studies and confrontations of observation with theory allow to progressively unravel the key processes underlying planet formation. In this chapter we review the dominant contribution of Doppler spectroscopy to the present discoveries and to our general understanding of planetary systems. We also emphasize the synergy of Doppler spectroscopy and transit photometry in characterizing the physical properties of transiting extrasolar planets. As we will see, Doppler spectroscopy has not reached its limits yet and it will undoubtly play a leading role in the detection and characterization of the first Earth-mass planets.