The EPRV Research Coordination Network (RCN), sponsored by NASA’s Exoplanet Exploration Program, aims to support increased communication and collaboration within the radial velocity community as we work towards the goal of obtaining robust mass measurements for Earth analog planets.

Membership is open to the community and we invite participants from all corners of the RV community and related fields, including but not limited to: observational efforts, instrumentation, data analysis techniques, solar studies, and stellar variability mitigation. Please see the side bar for instructions / links on how to join the RCN.

Our next EPRV colloquium will take place on June 22nd and feature Dr. Connor Fredrick [NIST / CU Boulder] who will discuss their recent work on solar heterodyne spectroscopy using laser frequency combs. Recordings of previous colloquia are available via the RCN Google Drive.

Advertisement for the next EPRV Colloquium on June 22nd 2023, which will feature Dr. Connor Fredrick

Abstract: Laser heterodyne radiometry (LHR) enables high-resolution spectroscopy with a compact apparatus consisting of single-mode fiber and RF components. By simultaneously performing LHR against sunlight and a laser frequency comb we can achieve high-precision solar spectroscopy with long-term absolute frequency accuracy, and using this system we have demonstrated <1m/s RV precision on single lines in the 1.5um region with resolution of R~1 million. The presentation will focus on the instrument design, our recent results, and what the longer term potential of these types of observations might be.

Background on the RCN

The 2018 National Academies’ Exoplanet Science Strategy, which provided input to the Astro 2020 Decadal Survey, acknowledged the importance of the radial velocity method “to provide essential mass, orbit, and census information to support both transiting and directly imaged exoplanet science for the foreseeable future” and recommended that “NASA and NSF should establish a strategic initiative in extremely precise radial velocities (EPRV) to develop methods and facilities for measuring the masses of temperate terrestrial planets orbiting Sun-like stars.” Subsequently, a community Extreme Precision Radial Velocity (EPRV) Working Group was chartered, which developed a roadmap for advancing the radial velocity technique to the point where EPRV detection or exclusion of Earth analogs orbiting nearby target stars of a future direct imaging mission would be feasible.

With the Astro2020 Decadal Survey recommendation for NASA to develop a large infrared/optical/ultraviolet space telescope capable of observing and spectrally characterizing potentially habitable exoplanets orbiting nearby stars, development of EPRV capabilities is critical as they will provide the only method potentially capable of discovering Earth analogs from the ground and measuring their masses. As part of its plan to “break the stellar variability barrier” and work towards enabling EPRV surveys capable of measuring the masses of Earth analogs, the EPRV WG report recommended that NASA establish an EPRV Research Coordination Network (RCN) of scientists across disciplines (solar, stellar, exoplanetary) and instruments.“ Thus, the development of this RCN, which endeavors to support the EPRV community in advancing towards the goal of detecting temperate, terrestrial, planets around Sun-like stars.