The CARMENES search for exoplanets around M dwarfs -- LP 714-47b (TOI 442.01): Populating the Neptune desert
Creators: name: Dreizler, S.
name: I.
name: J.
name: Crossfield, M.
name: Kossakowski, D.
name: Plavchan, P.
name: S.
name: Jeffers, V.
name: Kemmer, J.
name: Luque, R.
name: Espinoza, N.
name: Pallé, E.
name: Stassun, K.
name: Matthews, E.
name: Cale, B.
name: J.
name: Caballero, A.
name: Schlecker, M.
name: Lillo-Box, J.
name: Zechmeister, M.
name: Lalitha, S.
name: Reiners, A.
name: Soubkiou, A.
name: Bitsch, B.
name: M.
name: Osorio, R. Zapatero
name: Chaturvedi, P.
name: A.
name: Hatzes, P.
name: Ricker, G.
name: Vanderspek, R.
name: D.
name: Latham, W.
name: Seager, S.
name: Winn, J.
name: Jenkins, J. M.
name: Aceituno, J.
name: P.
name: Amado, J.
name: Barkaoui, K.
name: Barbieri, M.
name: N.
name: Batalha, M.
name: F.
name: Bauer, F.
name: Benneke, B.
name: Benkhaldoun, Z.
name: C
name: Beichman
name: Berberian, J.
name: Burt, J.
name: R.
name: Butler, P.
name: D.
name: Caldwell, A.
name: Chintada, A.
name: Chontos, A.
name: J.
name: Christiansen, L.
name: Ciardi, D. R.
name: Cifuentes, C.
name: K.
name: Collins, A.
name: K.
name: Collins, I.
name: Combs, D.
name: Cortés-Contreras, M.
name: J.
name: Crane, D.
name: Daylan, T.
name: Dragomir, D.
name: Esparza-Borges, E.
name: Evans, P.
name: Feng, F.
name: E.
name: Flowers, E.
name: Fukui, A.
name: Fulton, B.
name: Furlan, E.
name: Gaidos, E.
name: Geneser, C.
name: Giacalone, S.
name: Gillon, M.
name: Gonzales, E.
name: Gorjian, V.
name: Hellier, C.
name: Hidalgo, D.
name: A.
name: Howard, W.
name: Howell, S.
name: Huber, D.
name: Isaacson, H.
name: Jehin, E.
name: E.
name: L.
name: Jensen, N.
name: Kaminski, A.
name: S.
name: Kane, R.
name: Kawauchi, K.
name: J.
name: Kielkopf, F.
name: Klahr, H.
name: M.
name: Kosiarek, R.
name: Kreidberg, L.
name: M.
name: Kürster
name: Lafarga, M.
name: Livingston, J.
name: Louie, D.
name: Mann, A.
name: Madrigal-Aguado, A.
name: R.
name: Matson, A.
name: Mocnik, T.
name: J.
name: Morales, C.
name: P.
name: Muirhead, S.
name: Murgas, F.
name: Nandakumar, S.
name: Narita, N.
name: Nowak, G.
name: Oshagh, M.
name: Parviainen, H.
name: V.
name: Passegger, M.
name: Pollacco, D.
name: F.
name: Pozuelos, J.
name: Quirrenbach, A.
name: Reefe, M.
name: Ribas, I.
name: Robertson, P.
name: Rodríguez-López, C.
name: M.
name: Rose, E.
name: Roy, A.
name: Schweitzer, A.
name: Schlieder, J.
name: Shectman, S.
name: Tanner, A.
name: H.
name: Şenavcı, V.
name: Teske, J.
name: J.
name: Twicken, D.
name: Villasenor, J.
name: Wang, S. X.
name: L.
name: Weiss, M.
name: Wittrock, J.
name: Yılmaz, M.
name: Zohrabi, F.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences
subject: FOS: Physical sciences

description: We report the discovery of a Neptune-like planet (LP 714-47 b, P = 4.05204 d, m_b = 30.8 +/- 1.5 M_earth , R_b = 4.7 +/- 0.3 R_earth ) located in the 'hot Neptune desert'. Confirmation of the TESS Object of Interest (TOI 442.01) was achieved with radial-velocity follow-up using CARMENES, ESPRESSO, HIRES, iSHELL, and PFS, as well as from photometric data using TESS, Spitzer, and ground-based photometry from MuSCAT2, TRAPPIST- South, MONET-South, the George Mason University telescope, the Las Cumbres Observatory Global Telescope network, the El Sauce telescope, the TUBITAK National Observatory, the University of Louisville Manner Telescope, and WASP-South. We also present high-spatial resolution adaptive optics imaging with the Gemini Near-Infrared Imager. The low uncertainties in the mass and radius determination place LP 714-47 b among physically well-characterised planets, allowing for a meaningful comparison with planet structure models. The host star LP 714-47 is a slowly rotating early M dwarf (T_eff = 3950 +/- 51 K) with a mass of 0.59 +/- 0.02 M_sun and a radius of 0.58 +/- 0.02 R_sun. From long-term photometric monitoring and spectroscopic activity indicators, we determine a stellar rotation period of about 33 d. The stellar activity is also manifested as correlated noise in the radial-velocity data. In the power spectrum of the radial-velocity data, we detect a second signal with a period of 16 days in addition to the four-day signal of the planet. This could be shown to be a harmonic of the stellar rotation period or the signal of a second planet. It may be possible to tell the difference once more TESS data and radial-velocity data are obtained.
description: Accepted for publication in A&amp;A. 24 pages, 21 figures, 5 tables