A low-mass sub-Neptune planet transiting the bright active star HD 73344
2024
Online
report
Zugriff:
Context. Planets with radii of between 2-4 RE closely orbiting solar-type stars are of significant importance for studying the transition from rocky to giant planets. Aims. Our goal is to determine the mass of a transiting planet around the very bright F6 star HD 73344 . This star exhibits high activity and has a rotation period that is close to the orbital period of the planet. Methods. The transiting planet, initially a K2 candidate, is confirmed through TESS observations . We refined its parameters and rule out a false positive with Spitzer observations. We analyzed high-precision RV data from the SOPHIE and HIRES spectrographs. We conducted separate and joint analyses using the PASTIS software. We used a novel observing strategy, targeting the star at high cadence for two consecutive nights with SOPHIE to understand the short-term stellar variability. We modeled stellar noise with two Gaussian processes. Results. High-cadence RV observations provide better constraints on stellar variability and precise orbital parameters for the transiting planet. The derived mean density suggests a sub-Neptune-type composition, but uncertainties in the planet's mass prevent a detailed characterization. In addition, we find a periodic signal in the RV data that we attribute to the signature of a nontransiting exoplanet, without totally excluding the possibility of a nonplanetary origin. Dynamical analyses confirm the stability of the two-planet system and provide constraints on the inclination of the candidate planet; these findings favor a near-coplanar system. Conclusions. While the transiting planet orbits the bright star at a short period, stellar activity prevented us from precise mass measurements. Long-term RV tracking of this planet could improve this measurement, as well as our understanding of the activity of the host star.
Comment: Accepted for publication in Astronomy and Astrophysics
Titel: |
A low-mass sub-Neptune planet transiting the bright active star HD 73344
|
---|---|
Autor/in / Beteiligte Person: | Sulis, S. ; Crossfield, I. J. M. ; Santerne, A. ; Saillenfest, M. ; Sousa, S. ; Mary, D. ; Aguichine, A. ; Deleuil, M. ; Mena, E. Delgado ; Mathur, S. ; Polanski, A. ; Adibekyan, V. ; Boisse, I. ; Costes, J. C. ; Cretignier, M. ; Heidari, N. ; Lebarbé, C. ; Forveille, T. ; Hara, N. ; Meunier, N. ; Santos, N. ; Balcarcel-Salazar, S. ; Cortés-Zuleta, P. ; Dalal, S. ; Gorjian, V. ; Halverson, S. ; Howard, A. W. ; Kosiarek, M. R. ; Lopez, T. A. ; Martin, D. V. ; Mousis, O. ; Rajkumar, B. ; Ström, P. A. ; Udry, S. ; Venot, O. ; Willett, E. |
Link: | |
Veröffentlichung: | 2024 |
Medientyp: | report |
DOI: | 10.1051/0004-6361/202449559 |
Schlagwort: |
|
Sonstiges: |
|