TY - JOUR
T1 - Utilizing photometry from multiple sources to mitigate stellar variability in precise radial velocities
T2 - A case study of Kepler-21
AU - Beard, Corey
AU - Robertson, Paul
AU - Giovinazzi, Mark R.
AU - Murphy, Joseph M. Akana
AU - Ford, Eric B.
AU - Halverson, Samuel
AU - Han, Te
AU - Holcomb, Rae
AU - Lubin, Jack
AU - Luque, Rafael
AU - Premnath, Pranav
AU - Bender, Chad F.
AU - Blake, Cullen H.
AU - Gong, Qian
AU - Isaacson, Howard
AU - Kanodia, Shubham
AU - Li, Dan
AU - Lin, Andrea S. J.
AU - Logsdon, Sarah E.
AU - Lubar, Emily
AU - McElwain, Michael W.
AU - Monson, Andrew
AU - Ninan, Joe P.
AU - Rajagopal, Jayadev
AU - Roy, Arpita
AU - Schwab, Christian
AU - Stefansson, Gudmundur
AU - Terrien, Ryan C.
AU - Wright, Jason T.
N1 - © 2024. The Author(s). Published by the American Astronomical Society. Version archived for private and non-commercial use with the permission of the author/s and according to publisher conditions. For further rights please contact the publisher.
PY - 2024/10/1
Y1 - 2024/10/1
N2 - We present a new analysis of Kepler-21, the brightest (V = 8.5) Kepler system with a known transiting exoplanet, Kepler-21 b. Kepler-21 b is a radius valley planet (R = 1.6 ± 0.2R⊕) with an Earth-like composition (8.38 ± 1.62 g cm-3), though its mass and radius fall in the regime of possible “water worlds.” We utilize new Keck/High-Resolution Echelle Spectrometer and WIYN/NEID radial velocity (RV) data in conjunction with Kepler and Transiting Exoplanet Survey Satellite (TESS) photometry to perform a detailed study of activity mitigation between photometry and RVs. We additionally refine the system parameters, and we utilize Gaia astrometry to place constraints on a long-term RV trend. Our activity analysis affirms the quality of Kepler photometry for removing correlated noise from RVs, despite its temporal distance, though we reveal some cases where TESS may be superior. Using refined orbital parameters and updated composition curves, we rule out a water world scenario for Kepler-21 b, and we identify a long-period super-Jupiter planetary candidate, Kepler-21 (c).
AB - We present a new analysis of Kepler-21, the brightest (V = 8.5) Kepler system with a known transiting exoplanet, Kepler-21 b. Kepler-21 b is a radius valley planet (R = 1.6 ± 0.2R⊕) with an Earth-like composition (8.38 ± 1.62 g cm-3), though its mass and radius fall in the regime of possible “water worlds.” We utilize new Keck/High-Resolution Echelle Spectrometer and WIYN/NEID radial velocity (RV) data in conjunction with Kepler and Transiting Exoplanet Survey Satellite (TESS) photometry to perform a detailed study of activity mitigation between photometry and RVs. We additionally refine the system parameters, and we utilize Gaia astrometry to place constraints on a long-term RV trend. Our activity analysis affirms the quality of Kepler photometry for removing correlated noise from RVs, despite its temporal distance, though we reveal some cases where TESS may be superior. Using refined orbital parameters and updated composition curves, we rule out a water world scenario for Kepler-21 b, and we identify a long-period super-Jupiter planetary candidate, Kepler-21 (c).
UR - http://www.scopus.com/inward/record.url?scp=85204355616&partnerID=8YFLogxK
U2 - 10.3847/1538-3881/ad6b22
DO - 10.3847/1538-3881/ad6b22
M3 - Article
AN - SCOPUS:85204355616
SN - 0004-6256
VL - 168
SP - 1
EP - 17
JO - Astronomical Journal
JF - Astronomical Journal
IS - 4
M1 - 149
ER -