An ultra-short-period transiting super-Earth orbiting the M3 dwarf TOI-1685
Abstract
Dynamical histories of planetary systems, as well as atmospheric evolution of highly irradiated planets, can be studied by characterizing the ultra-short-period planet population, which the TESS mission is particularly well suited to discover. Here, we report on the follow-up of a transit signal detected in the TESS sector 19 photometric time series of the M3.0 V star TOI-1685 (2MASS J04342248+4302148). We confirm the planetary nature of the transit signal, which has a period of P_b=0.6691403+0.0000023-0.0000021 d, using precise radial velocity measurements taken with the CARMENES spectrograph. From the joint photometry and radial velocity analysis, we estimate the following parameters for TOI-1685 b: a mass of M_b=3.78+/-0.63 M_Earth, a radius of R_b=1.70+/-0.07 R_Earth, which together result in a bulk density of rho_b=4.21+0.95-0.82 g/cm3, and an equilibrium temperature of Teq_b=1069+/-16 K. TOI-1685 b is the least dense ultra-short period planet around an M dwarf known to date. TOI-1685 b is also one of the hottest transiting Earth-size planets with accurate dynamical mass measurements, which makes it a particularly attractive target for thermal emission spectroscopy. Additionally, we report a further non-transiting planet candidate in the system, TOI-1685[c], with an orbital period of P_[c]=9.02+0.10-0.12 d.
Cite
@article{arxiv.2103.01016,
title = {An ultra-short-period transiting super-Earth orbiting the M3 dwarf TOI-1685},
author = {P. Bluhm and E. Palle and K. Molaverdikhani and J. Kemmer and A. P. Hatzes and D. Kossakowski and S. Stock and J. A. Caballero and J. Lillo-Box and V. J. S . Bejar and M. G. Soto and P. J. Amado and P. Brown and C. Cadieux and R. Cloutier and K. A. Collins and K. I. Collins and M. Cortes-Contreras and R. Doyon and S. Dreizler and N. Espinoza and A. Fukui and E. Gonzalez-Alvarez and Th. Henning and K. Horne and S. V. Jeffers and J. M. Jenkins and E. L. N. Jensen and A. Kaminski and J. F. Kielkopf and N. Kusakabe and M. Kuerster and D. Lafreniere and R. Luque and F. Murgas and D. Montes and J. C. Morales and N. Narita and V. M. Passegger and A. Quirrenbach and P. Schoefer and S. Reffert and A. Reiners and I. Ribas and G. R. Ricker and S. Seager and A. Schweitzer and R. P. Schwarz and M. Tamura and T. Trifonov and R. Vanderspek and J. Winn and M. Zechmeister and M. R. Zapatero Osorio},
journal= {arXiv preprint arXiv:2103.01016},
year = {2021}
}
Comments
18 pages, 15 figures