The Astronomical Journal (Jan 2024)
Utilizing Photometry from Multiple Sources to Mitigate Stellar Variability in Precise Radial Velocities: A Case Study of Kepler-21
- Corey Beard,
- Paul Robertson,
- Mark R. Giovinazzi,
- Joseph M. Akana Murphy,
- Eric B. Ford,
- Samuel Halverson,
- Te Han,
- Rae Holcomb,
- Jack Lubin,
- Rafael Luque,
- Pranav Premnath,
- Chad F. Bender,
- Cullen H. Blake,
- Qian Gong,
- Howard Isaacson,
- Shubham Kanodia,
- Dan Li,
- Andrea S. J. Lin,
- Sarah E. Logsdon,
- Emily Lubar,
- Michael W. McElwain,
- Andrew Monson,
- Joe P. Ninan,
- Jayadev Rajagopal,
- Arpita Roy,
- Christian Schwab,
- Gudmundur Stefansson,
- Ryan C. Terrien,
- Jason T. Wright
Affiliations
- Corey Beard
- ORCiD
- Department of Physics & Astronomy, University of California , Irvine, CA 92697, USA ; [email protected]
- Paul Robertson
- ORCiD
- Department of Physics & Astronomy, University of California , Irvine, CA 92697, USA ; [email protected]
- Mark R. Giovinazzi
- ORCiD
- Department of Physics and Astronomy, University of Pennsylvania , 209 S 33rd Street, Philadelphia, PA 19104, USA
- Joseph M. Akana Murphy
- ORCiD
- Department of Astronomy and Astrophysics, University of California , Santa Cruz, CA 95064, USA
- Eric B. Ford
- ORCiD
- Department of Astronomy & Astrophysics, 525 Davey Laboratory, Penn State , University Park, PA 16802, USA; Center for Exoplanets and Habitable Worlds, 525 Davey Laboratory, Penn State , University Park, PA 16802, USA; Institute for Computational and Data Sciences, Penn State , University Park, PA 16802, USA; Center for Astrostatistics, 525 Davey Laboratory, Penn State , University Park, PA 16802, USA
- Samuel Halverson
- ORCiD
- Jet Propulsion Laboratory, California Institute of Technology , 4800 Oak Grove Drive, Pasadena, CA 91109, USA
- Te Han
- ORCiD
- Department of Physics & Astronomy, University of California , Irvine, CA 92697, USA ; [email protected]
- Rae Holcomb
- ORCiD
- Department of Physics & Astronomy, University of California , Irvine, CA 92697, USA ; [email protected]
- Jack Lubin
- ORCiD
- Department of Physics & Astronomy, University of California, Los Angeles , CA 90095, USA
- Rafael Luque
- ORCiD
- Department of Astronomy & Astrophysics, University of Chicago , Chicago, IL 60637, USA
- Pranav Premnath
- ORCiD
- Department of Physics & Astronomy, University of California , Irvine, CA 92697, USA ; [email protected]
- Chad F. Bender
- ORCiD
- Steward Observatory, University of Arizona , 933 N. Cherry Avenue, Tucson, AZ 85721, USA
- Cullen H. Blake
- ORCiD
- Department of Physics and Astronomy, University of Pennsylvania , 209 S 33rd Street, Philadelphia, PA 19104, USA
- Qian Gong
- ORCiD
- Instrument Systems and Technology Division, NASA Goddard Space Flight Center , Greenbelt, MD 20771, USA
- Howard Isaacson
- ORCiD
- 501 Campbell Hall, University of California at Berkeley , Berkeley, CA 94720, USA; Centre for Astrophysics, University of Southern Queensland , Toowoomba, QLD 4350, Australia
- Shubham Kanodia
- ORCiD
- Earth and Planets Laboratory, Carnegie Institution for Science , 5241 Broad Branch Road, NW, Washington, DC 20015, USA
- Dan Li
- ORCiD
- NSF’s National Optical-Infrared Astronomy Research Laboratory , 950 N. Cherry Avenue, Tucson, AZ 85719, USA
- Andrea S. J. Lin
- ORCiD
- Department of Astronomy & Astrophysics, 525 Davey Laboratory, Penn State , University Park, PA 16802, USA; Center for Exoplanets and Habitable Worlds, 525 Davey Laboratory, Penn State , University Park, PA 16802, USA
- Sarah E. Logsdon
- ORCiD
- NSF’s National Optical-Infrared Astronomy Research Laboratory , 950 N. Cherry Avenue, Tucson, AZ 85719, USA
- Emily Lubar
- ORCiD
- Aerospace Corporation , Building D8, 200 N Aviation Boulevard, El Segundo, CA 90245, USA
- Michael W. McElwain
- ORCiD
- Exoplanets and Stellar Astrophysics Laboratory, NASA Goddard Space Flight Center , Greenbelt, MD 20771, USA
- Andrew Monson
- ORCiD
- Steward Observatory, University of Arizona , 933 N. Cherry Avenue, Tucson, AZ 85721, USA
- Joe P. Ninan
- ORCiD
- Department of Astronomy and Astrophysics, Tata Institute of Fundamental Research , Homi Bhabha Road, Colaba, Mumbai 400005, India
- Jayadev Rajagopal
- ORCiD
- NSF’s National Optical-Infrared Astronomy Research Laboratory , 950 N. Cherry Avenue, Tucson, AZ 85719, USA
- Arpita Roy
- ORCiD
- Space Telescope Science Institute , 3700 San Martin Drive, Baltimore, MD 21218, USA; Department of Physics and Astronomy, Johns Hopkins University , 3400 N Charles Street, Baltimore, MD 21218, USA
- Christian Schwab
- ORCiD
- School of Mathematical and Physical Sciences, Macquarie University , Balaclava Road, North Ryde, NSW 2109, Australia
- Gudmundur Stefansson
- ORCiD
- Anton Pannekoek Institute for Astronomy, University of Amsterdam , Science Park 904, 1098 XH Amsterdam, The Netherlands
- Ryan C. Terrien
- ORCiD
- Carleton College , One North College Street, Northfield, MN 55057, USA
- Jason T. Wright
- ORCiD
- Department of Astronomy & Astrophysics, 525 Davey Laboratory, Penn State , University Park, PA 16802, USA; Center for Exoplanets and Habitable Worlds, 525 Davey Laboratory, Penn State , University Park, PA 16802, USA; Penn State Extraterrestrial Intelligence Center , 525 Davey Laboratory, Penn State, University Park, PA 16802, USA
- DOI
- https://doi.org/10.3847/1538-3881/ad6b22
- Journal volume & issue
-
Vol. 168,
no. 4
p. 149
Abstract
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 ± 0.2 R _⊕ ) 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).
Keywords
