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Title: STELLAR ACTIVITY AND EXCLUSION OF THE OUTER PLANET IN THE HD 99492 SYSTEM

A historical problem for indirect exoplanet detection has been contending with the intrinsic variability of the host star. If the variability is periodic, it can easily mimic various exoplanet signatures, such as radial velocity (RV) variations that originate with the stellar surface rather than the presence of a planet. Here we present an update for the HD 99492 planetary system, using new RV and photometric measurements from the Transit Ephemeris Refinement and Monitoring Survey. Our extended time series and subsequent analyses of the Ca ii H and K emission lines show that the host star has an activity cycle of ∼13 years. The activity cycle correlates with the purported orbital period of the outer planet, the signature of which is thus likely due to the host star activity. We further include a revised Keplerian orbital solution for the remaining planet, along with a new transit ephemeris. Our transit-search observations were inconclusive.
Authors:
; ;  [1] ;  [2] ;  [3] ; ;  [4] ;  [5] ;  [6] ;  [7]
  1. Department of Physics and Astronomy, San Francisco State University, 1600 Holloway Avenue, San Francisco, CA 94132 (United States)
  2. Center of Excellence in Information Systems, Tennessee State University, 3500 John A. Merritt Blvd., Box 9501, Nashville, TN 37209 (United States)
  3. Dept of Physics and Astronomy, Swarthmore College, Swarthmore, PA 19081 (United States)
  4. Department of Astronomy, Yale University, New Haven, CT 06511 (United States)
  5. Institute for Astronomy, University of Hawaii, Honolulu, HI 96822 (United States)
  6. Astronomy Department, University of California, Berkeley, CA 94720 (United States)
  7. Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Laboratory, University Park, PA 16802 (United States)
Publication Date:
OSTI Identifier:
22518581
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal Letters; Journal Volume: 820; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CALCIUM; DETECTION; EMISSION SPECTRA; HYDROGEN; PERIODICITY; PLANETS; POTASSIUM; RADIAL VELOCITY; STARS; STELLAR ACTIVITY