Publication details

TOI-1670 b and c: An Inner Sub-Neptune with an Outer Warm Jupiter Unlikely to Have Originated from High-eccentricity Migration

Authors	TRAN Quang H. BOWLER Brendan P. ENDL Michael COCHRAN William D. MACQUEEN Phillip J. GANDOLFI Davide PERSSON Carina M. FRIDLUND Malcolm PALLE Enric NOWAK Grzegorz DEEG Hans J. LUQUE Rafael LIVINGSTON John H. KABATH Petr SKARKA Marek SUBJAK Jan HOWELL Steve B. ALBRECHT Simon H. COLLINS Karen A. ESPOSITO Massimiliano VINCENT Van Eylen GRZIWA Sascha GOFFO Elisa HUANG Chelsea X. JENKINS Jon M. KARJALAINEN Marie KARJALAINEN Raine KNUDSTRUP Emil KORTH Judith LAM Kristine W. F. LATHAM David W. LEVINE Alan M. OSBORNE H. L. M. QUINN Samuel N. REDFIELD Seth RICKER George R. SEAGER S. SERRANO Luisa Maria SMITH Alexis M. S. TWICKEN Joseph D. WINN Joshua N.
Year of publication	2022
Type	Article in Periodical
Magazine / Source	Astronomical Journal
MU Faculty or unit	Faculty of Science
Citation
web	https://arxiv.org/pdf/2203.04334.pdf https://iopscience.iop.org/article/10.3847/1538-3881/ac5c4f
Doi	http://dx.doi.org/10.3847/1538-3881/ac5c4f
Keywords	planetary systems; planets and satellites: detection; stars: individual (TOI-1670)
Description	We report the discovery of two transiting planets around the bright (V = 9.9 mag) main-sequence F7 star TOI-1670 by the Transiting Exoplanet Survey Satellite. TOI-1670 b is a sub-Neptune (R-b = 2.06(-0.15)(+0.19) R-circle plus) on a 10.9 day orbit, and TOI-1670 c is a warm Jupiter (R-c= 0.987(-0.025)(+0.025) R-Jup) on a 40.7 day orbit. Using radial velocity observations gathered with the Tull Coude Spectrograph on the Harlan J. Smith telescope and HARPS-N on the Telescopio Nazionale Galileo, we find a planet mass of M-c = 0.63(-0.08)(+0.09) M(Jup )for the outer warm Jupiter, implying a mean density of rho(c) = 0.81(-0.11)(+0.13) g cm(-3). The inner sub-Neptune is undetected in our radial velocity data (M-b < 0.13 M-Jup at the 99% confidence level). Multiplanet systems like TOI-1670 hosting an outer warm Jupiter on a nearly circular orbit (l(e) = 0.09(-0.04)(+0.05)) and one or more inner coplanar planets are more consistent with "gentle" formation mechanisms such as disk migration or in situ formation rather than high-eccentricity migration. Of the 11 known systems with a warm Jupiter and a smaller inner companion, eight (73%) are near a low-order mean-motion resonance, which can be a signature of migration. TOI-1670 joins two other systems (27% of this subsample) with period commensurabilities greater than 3, a common feature of in situ formation or halted inward migration. TOI-1670 and the handful of similar systems support a diversity of formation pathways for warm Jupiters.