تقرير
TOI-544 b: a potential water-world inside the radius valley in a two-planet system
| العنوان: | TOI-544 b: a potential water-world inside the radius valley in a two-planet system |
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| المؤلفون: | Osborne, H. L. M., Van Eylen, V., Goffo, E., Gandolfi, D., Nowak, G., Persson, C. M., Livingston, J., Weeks, A., Pallé, E., Luque, R., Hellier, C., Carleo, I., Redfield, S., Hirano, T., Gili, M. Garbaccio, Alarcon, J., Barragán, O., Casasayas-Barris, N., Díaz, M. R., Esposito, M., Jenkins, J. S., Knudstrup, E., Murgas, F., Orell-Miquel, J., Rodler, F., Serrano, L., Stangret, M., Albrecht, S. H., Alqasim, A., Cochran, W. D., Deeg, H. J., Fridlund, M., Hatzes, A., Korth, J., Lam, K. W. F. |
| سنة النشر: | 2023 |
| المجموعة: | Astrophysics |
| مصطلحات موضوعية: | Astrophysics - Earth and Planetary Astrophysics |
| الوصف: | We report on the precise radial velocity follow-up of TOI-544 (HD 290498), a bright K star (V=10.8), which hosts a small transiting planet recently discovered by the Transiting Exoplanet Survey Satellite (TESS). We collected 122 high-resolution HARPS and HARPS-N spectra to spectroscopically confirm the transiting planet and measure its mass. The nearly 3-year baseline of our follow-up allowed us to unveil the presence of an additional, non-transiting, longer-period companion planet. We derived a radius and mass for the inner planet, TOI-544b, of 2.018 $\pm$ 0.076 R$_{\oplus}$ and 2.89 $\pm$ 0.48 M$_{\oplus}$ respectively, which gives a bulk density of $1.93^{+0.30}_{-0.25}$ g cm$^{-3}$. TOI-544c has a minimum mass of 21.5 $\pm$ 2.0 M$_{\oplus}$ and orbital period of 50.1 $\pm$ 0.2 days. The low density of planet-b implies that it has either an Earth-like rocky core with a hydrogen atmosphere, or a composition which harbours a significant fraction of water. The composition interpretation is degenerate depending on the specific choice of planet interior models used. Additionally, TOI-544b has an orbital period of 1.55 days and equilibrium temperature of 999 $\pm$ 14 K, placing it within the predicted location of the radius valley, where few planets are expected. TOI-544b is a top target for future atmospheric observations, for example with JWST, which would enable better constraints of the planet composition. Comment: Accepted in MNRAS, 06 December 2023 |
| نوع الوثيقة: | Working Paper |
| الوصول الحر: | http://arxiv.org/abs/2310.14908Test |
| رقم الانضمام: | edsarx.2310.14908 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |