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State of the Field: Extreme Precision Radial Velocities



Debra A. Fischer, Guillem Anglada-Escude, Pamela Arriagada, Roman V. Baluev, Jacob L. Bean, Lars A. Buchhave, Abhijit K. Chakraborty, Scott Diddams, Gabor Furesz, B. S. Gaudi, Philip C. Gregory, Frank Grundahl, Guillaume Hebrard, David W. Hogg, Andrew W. Howard, Colby A. Jurgenson, David W. Latham, Greg Laughlin, Thomas J. Loredo, Suvrath Mahadevan, Tyler M. McCracken, Mario R. Perez, David F. Phillips, P Plavchan, Lisa Prato, Andreas Quirrenbach, Paul Robertson, David Sawyer, Jason D. Eastman, Pedro Figueira, Eric B. Ford, Daniel Foreman-Mackey, Paul Fournier, John A. Johnson, Christophe Lovis, Francesco Pepe, Francesco Pepe, Ansgar Reiners, Nuno C. Santos, Damien Segransan, Alessandro Sozzetti, Thorsten Carroll, Francois Bouchy, Paul Jorden, Tilo Steinmetz, Xavier Dumusque, Artie P. Hatzes, Enrique Herrero, Michael Endl, Andrew Szentgyorgyi


The Second Workshop on Extreme Precision Radial Velocities defined circa 2015 the state of the art Doppler precision and identified the critical path challenges for reaching 10 cm/s measurement precision. The presentations and discussion of key issues for instrumentation and data analysis and the workshop recommendations for achieving this bold precision are summarized. Beginning with the HARPS spectrograph, technological advances for precision radial velocity measurements have focused on building extremely stable instruments. To reach still higher precision, future spectrometers will need to improve upon the state of the art, producing even higher fidelity spectra. This should be possible with improved spectrometer environmental control, greater stability in the illumination of the spectrometer optics, better detectors, more precise wavelength calibration, and broader bandwidth spectra. Key data analysis challenges for the precision radial velocity community include distinguishing center of mass Keplerian motion from photospheric velocities and the proper treatment of telluric contamination. Success coupled to the instrument design, but also requires the implementation of robust statistical and modeling techniques. Center of mass velocities produce Doppler shifts that affect every line identically, while photospheric velocities produce line profile asymmetries with wavelength and temporal dependencies that are different from Keplerian signals. Exoplanets are an important subfield of astronomy and there has been an impressive rate of discovery over the past two decades. Higher precision radial velocity measurements are required to serve as a discovery technique for potentially habitable worlds, to confirm and characterize detections from transit missions, and to provide mass measurements for other space-based missions. The future of exoplanet science has very different trajectories depending on the precision that can ultimately be achieved with Doppler measurements.
Publications of the Astronomical Society of the Pacific


Doppler shift, Exoplanet, Frequency comb, Radial Velocity


Fischer, D. , Anglada-Escude, G. , Arriagada, P. , Baluev, R. , Bean, J. , Buchhave, L. , Chakraborty, A. , Diddams, S. , Furesz, G. , Gaudi, B. , Gregory, P. , Grundahl, F. , Hebrard, G. , Hogg, D. , Howard, A. , Jurgenson, C. , Latham, D. , Laughlin, G. , Loredo, T. , Mahadevan, S. , McCracken, T. , Perez, M. , Phillips, D. , Plavchan, P. , Prato, L. , Quirrenbach, A. , Robertson, P. , Sawyer, D. , Eastman, J. , Figueira, P. , Ford, E. , Foreman-Mackey, D. , Fournier, P. , Johnson, J. , Lovis, C. , Pepe, F. , Pepe, F. , Reiners, A. , Santos, N. , Segransan, D. , Sozzetti, A. , Carroll, T. , Bouchy, F. , Jorden, P. , Steinmetz, T. , Dumusque, X. , Hatzes, A. , Herrero, E. , Endl, M. and Szentgyorgyi, A. (2016), State of the Field: Extreme Precision Radial Velocities, Publications of the Astronomical Society of the Pacific (Accessed June 10, 2023)
Created May 16, 2016, Updated October 12, 2021