A low-mass sub-Neptune planet transiting the bright active star HD 73344

التفاصيل البيبلوغرافية
العنوان: A low-mass sub-Neptune planet transiting the bright active star HD 73344
المؤلفون: 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.
سنة النشر: 2024
المجموعة: Astrophysics
مصطلحات موضوعية: Astrophysics - Earth and Planetary Astrophysics, Astrophysics - Solar and Stellar Astrophysics
الوصف: 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
نوع الوثيقة: Working Paper
DOI: 10.1051/0004-6361/202449559
URL الوصول: http://arxiv.org/abs/2405.17155
رقم الأكسشن: edsarx.2405.17155
قاعدة البيانات: arXiv
الوصف
DOI:10.1051/0004-6361/202449559