Academic Journal

Characterising TOI-732 b and c: New insights into the M-dwarf radius and density valley

التفاصيل البيبلوغرافية
العنوان: Characterising TOI-732 b and c: New insights into the M-dwarf radius and density valley
المؤلفون: Bonfanti, A., Brady, M., Wilson, T. G., Venturini, J., Egger, J. A., Brandeker, A., Sousa, S. G., Lendl, M., Simon, A. E., Queloz, D., Olofsson, G., Adibekyan, V., Alibert, Y., Fossati, L., Hooton, M. J., Kubyshkina, D., Mustill, A. J., Luque, R., Murgas, F., Santos, N. C., Van Grootel, V., Alonso, R., Asquier, J., Bandy, T., Bárczy, T., Barrado Navascues, D., Barros, S. C. C., Baumjohann, W., Bean, J., Beck, M., Beck, T., Benz, W., Bergomi, M., Billot, N., Borsato, L., Broeg, C., Collier Cameron, A., Csizmadia, Sz., Cubillos, P. E., Davies, M. B., Deleuil, M., Deline, A., Delrez, L., Demangeon, O. D. S., Demory, B.-O., Ehrenreich, D., Erikson, A., Fortier, A., Fridlund, M., Gandolfi, D., Gillon, M., Güdel, M., Günther, M. N., Heitzmann, A., Helling, Ch., Hoyer, S., Isaak, K. G., Kasper, D., Kiss, L. L., Lam, K. W. F., Laskar, J., Lecavelier des Etangs, A., Magrin, D., Maxted, P. F. L., Mordasini, C., Nascimbeni, V., Ottensamer, R., Pagano, I., Pallé, E., Peter, G., Piotto, G., Pollacco, D., Ragazzoni, R., Rando, N., Rauer, H., Ribas, I., Scandariato, G., Ségransan, D., Seifahrt, A., Smith, A. M. S., Stalport, M., Stefánsson, G., Steinberger, M., Stürmer, J., Szabó, Gy. M., Thomas, N., Udry, S., Villaver, E., Walton, N. A., Westerdorff, K., Zingales, T.
المصدر: Bonfanti, A.; Brady, M.; Wilson, T. G.; Venturini, J.; Egger, J. A.; Brandeker, A.; Sousa, S. G.; Lendl, M.; Simon, A. E.; Queloz, D.; Olofsson, G.; Adibekyan, V.; Alibert, Y.; Fossati, L.; Hooton, M. J.; Kubyshkina, D.; Mustill, A. J.; Luque, R.; Murgas, F.; Santos, N. C.; . (2024). Characterising TOI-732 b and c: New insights into the M-dwarf radius and density valley. Astronomy and astrophysics, 682 EDP Sciences 10.1051/0004-6361/202348180
بيانات النشر: EDP Sciences
سنة النشر: 2024
المجموعة: BORIS (Bern Open Repository and Information System, University of Bern)
مصطلحات موضوعية: 000 Computer science, knowledge & systems, 520 Astronomy, 530 Physics, 620 Engineering
الوصف: Context. TOI-732 is an M dwarf hosting two transiting planets that are located on the two opposite sides of the radius valley. Inferring a reliable demographics for this type of systems is key to understanding their formation and evolution mechanisms. Aims. By doubling the number of available space-based observations and increasing the number of radial velocity (RV) measurements, we aim at refining the parameters of TOI-732 b and c. We also use the results to study the slope of the radius valley and the density valley for a well-characterised sample of M-dwarf exoplanets. Methods. We performed a global Markov chain Monte Carlo analysis by jointly modelling ground-based light curves and CHEOPS and TESS observations, along with RV time series both taken from the literature and obtained with the MAROON-X spectrograph. The slopes of the M-dwarf valleys were quantified via a support vector machine (SVM) procedure. Results. TOI-732b is an ultrashort-period planet (P = 0.76837931-0.00000042+0.0000039 days) with a radius Rb = 1.325-0.058+0.057R⊕, a mass Mb = 2.46 ± 0.19 M⊕, and thus a mean density ρb = 5.8-0.8+1.0 g cm-3, while the outer planet at P = 12.252284 ± 0.000013 days has Rc = 2.39-0.11+0.10R⊕, Mc = 8.04-0.48+0.50M⊕, and thus ρc = 3.24-0.43+0.55 g cm-3. Even with respect to the most recently reported values, this work yields uncertainties on the transit depths and on the RV semi-amplitudes that are smaller up to a factor of ~1.6 and ~2.4 for TOI-732 b and c, respectively. Our calculations for the interior structure and the location of the planets in the mass-radius diagram lead us to classify TOI-732 b as a super-Earth and TOI-732 c as a mini-Neptune. Following the SVM approach, we quantified d log Rp,valley / d logP = -0.065-0.013+0.024, which is flatter than for Sun-like stars. In line with former analyses, we note that the radius valley for M-dwarf planets is more densely populated, and we further quantify the slope of the density valley as d log ρ^valley / d log P = -0.02-0.04+0.12. Conclusions. Compared to ...
نوع الوثيقة: article in journal/newspaper
وصف الملف: application/pdf
اللغة: English
Relation: https://boris.unibe.ch/195624/
الاتاحة: https://boris.unibe.ch/195624/1/aa48180-23.pdf
https://boris.unibe.ch/195624/
Rights: info:eu-repo/semantics/openAccess
رقم الانضمام: edsbas.E6CEDAD6
قاعدة البيانات: BASE