21 research outputs found
TOI-150b and TOI-163b: two transiting hot Jupiters, one eccentric and one inflated, revealed by TESS near and at the edge of the JWST CVZ
We present the discovery of TYC9191-519-1b (TOI-150b, TIC 271893367) and HD271181b (TOI-163b, TIC 179317684), two hot Jupiters initially detected using 30-min cadence Transiting Exoplanet Survey Satellite (TESS) photometry from Sector 1 and thoroughly characterized through follow-up photometry (CHAT, Hazelwood, LCO/CTIO, El Sauce, TRAPPIST-S), high-resolution spectroscopy (FEROS, CORALIE), and speckle imaging (Gemini/DSSI), confirming the planetary nature of the two signals. A simultaneous joint fit of photometry and radial velocity using a new fitting package JULIET reveals that TOI-150b is a 1.254±0.016 R_Jâ , massive (â 2.61^(+0.19)_(â0.12) M_J) hot Jupiter in a 5.857-d orbit, while TOI-163b is an inflated (â R_P = 1.478^(+0.022)_(â0.029) R_Jâ , M_P = 1.219±0.11M_J) hot Jupiter on a P = 4.231-d orbit; both planets orbit F-type stars. A particularly interesting result is that TOI-150b shows an eccentric orbit (â e = 0.262^(+0.045)_(â0.037)â ), which is quite uncommon among hot Jupiters. We estimate that this is consistent, however, with the circularization time-scale, which is slightly larger than the age of the system. These two hot Jupiters are both prime candidates for further characterization â in particular, both are excellent candidates for determining spin-orbit alignments via the RossiterâMcLaughlin (RM) effect and for characterizing atmospheric thermal structures using secondary eclipse observations considering they are both located closely to the James Webb Space Telescope (JWST) Continuous Viewing Zone (CVZ)
New HARPS and FEROS observations of GJ1046
In this paper we present new precise Doppler data of GJ1046 taken between
November 2005 and July 2018 with the HARPS and the FEROS high-resolution
spectographs. In addition, we provide a new stellar mass estimate of GJ1046 and
we update the orbital parameters of the GJ1046 system. These new data and
analysis could be used together with the GAIA epoch astrometry, when available,
for braking the degeneracy and revealing the true mass of the GJ1046
system.Comment: 2 pages, 1 figure, 1 table with RV data (available only in the
Astro-PH version of the paper), Accepted by RNAA
HD 213885b: a transiting 1-d-period super-Earth with an Earth-like composition around a bright (V = 7.9) star unveiled by TESS
We report the discovery of the 1.008-d, ultrashort period (USP) super-Earth HD 213885b (TOI-141b) orbiting the bright (V = 7.9) star HD 213885 (TOI-141, TIC 403224672), detected using photometry from the recently launched TESS mission. Using FEROS, HARPS, and CORALIE radial velocities, we measure a precise mass of 8.8 ± 0.6âMâ for this 1.74 ± 0.05âRâ exoplanet, which provides enough information to constrain its bulk composition â similar to Earthâs but enriched in iron. The radius, mass, and stellar irradiation of HD 213885b are, given our data, very similar to 55 Cancri e, making this exoplanet a good target to perform comparative exoplanetology of short period, highly irradiated super-Earths. Our precise radial velocities reveal an additional 4.78-d signal which we interpret as arising from a second, non-transiting planet in the system, HD 213885c, whose minimum mass of 19.9 ± 1.4âMâ makes it consistent with being a Neptune-mass exoplanet. The HD 213885 system is very interesting from the perspective of future atmospheric characterization, being the second brightest star to host an USP transiting super-Earth (with the brightest star being, in fact, 55 Cancri). Prospects for characterization with present and future observatories are discussed
TOI-199 b: A well-characterized 100-day transiting warm giant planet with TTVs seen from Antarctica
We present the spectroscopic confirmation and precise mass measurement of the
warm giant planet TOI-199 b. This planet was first identified in TESS
photometry and confirmed using ground-based photometry from ASTEP in Antarctica
including a full 6.5h long transit, PEST, Hazelwood, and LCO; space
photometry from NEOSSat; and radial velocities (RVs) from FEROS, HARPS,
CORALIE, and CHIRON. Orbiting a late G-type star, TOI-199\,b has a
period, a mass of
, and a radius of .
It is the first warm exo-Saturn with a precisely determined mass and radius.
The TESS and ASTEP transits show strong transit timing variations, pointing to
the existence of a second planet in the system. The joint analysis of the RVs
and TTVs provides a unique solution for the non-transiting companion TOI-199 c,
which has a period of and an estimated
mass of . This period places it within
the conservative Habitable Zone.Comment: 33 pages, 23 figures. Accepted for publication in A
Three long period transiting giant planets from TESS
We report the discovery and orbital characterization of three new transiting
warm giant planets. These systems were initially identified as presenting
single transit events in the light curves generated from the full frame images
of the Transiting Exoplanet Survey Satellite (TESS). Follow-up radial velocity
measurements and additional light curves were used to determine the orbital
periods and confirm the planetary nature of the candidates. The planets orbit
slightly metal-rich late F- and early G-type stars. We find that TOI 4406b has
a mass of = 0.30 0.04 , a radius of = 1.00 0.02
, and a low eccentricity orbit (e=0.15 0.05) with a period of P=
30.08364 0.00005 d . TOI 2338b has a mass of = 5.98 0.20
, a radius of = 1.00 0.01 , and a highly eccentric orbit (e=
0.676 0.002 ) with a period of P= 22.65398 0.00002 d . Finally, TOI
2589b has a mass of = 3.50 0.10 , a radius of = 1.08
0.03 , and an eccentric orbit (e = 0.522 0.006 ) with a
period of P= 61.6277 0.0002 d . TOI 4406b and TOI 2338b are enriched in
metals compared to their host stars, while the structure of TOI 2589b is
consistent with having similar metal enrichment to its host star.Comment: 24 pages, 16 figures, accepted in A
TOI-677 b: A Warm Jupiter (P=11.2d) on an eccentric orbit transiting a late F-type star
We report the discovery of TOI-677 b, first identified as a candidate in
light curves obtained within Sectors 9 and 10 of the Transiting Exoplanet
Survey Satellite (TESS) mission and confirmed with radial velocities. TOI-677 b
has a mass of M_p = 1.236 M_J, a radius of R_p = 1.170 +-
0.03 R_J,and orbits its bright host star (V=9.8 mag) with an orbital period of
11.23660 +- 0.00011 d, on an eccentric orbit with e = 0.435 +- 0.024. The host
star has a mass of M_* = 1.181 +- 0.058 M_sun, a radius of R_* = 1.28 +- 0.03
R_sun, an age of 2.92 Gyr and solar metallicity, properties
consistent with a main sequence late F star with T_eff = 6295 +- 77 K. We find
evidence in the radial velocity measurements of a secondary long term signal
which could be due to an outer companion. The TOI-677 b system is a well suited
target for Rossiter-Mclaughlin observations that can constrain migration
mechanisms of close-in giant planets.Comment: Submitted to AAS journals, 15 pages, 8 figure