4 research outputs found
TOI-712:a system of adolescent mini-Neptunes extending to the habitable zone
As an all-sky survey, NASA's mission is able to detect the brightest
and rarest types of transiting planetary systems, including young planets that
enable study of the evolutionary processes that occur within the first billion
years. Here, we report the discovery of a young, multi-planet system orbiting
the bright K4.5V star, TOI-712 (, , , K). From the light curve, we measure a rotation
period of 12.48 days, and derive an age between about Myr and 1.1 Gyr.
The photometric observations reveal three transiting mini-Neptunes (, ,
), with orbital periods of days, days, and days. After modeling the
three-planet system, an additional Earth-sized candidate is identified,
TOI-712.05 ( days, ). We calculate that
the habitable zone falls between 0.339 and 0.844 au (82.7 and 325.3 days),
placing TOI-712 d near its inner edge. Among planetary systems harboring
temperate planets, TOI-712 () stands out as a relatively young star
bright enough to motivate further characterization.Comment: 20 pages, 11 figures, 5 tables, submitted to AAS Journal
Spinning up a Daze: TESS Uncovers a Hot Jupiter orbiting the Rapid-Rotator TOI-778
NASA's Transiting Exoplanet Survey Satellite (TESS) mission, has been uncovering a growing number of exoplanets orbiting nearby, bright stars. Most exoplanets that have been discovered by TESS orbit narrow-line, slow-rotating stars, facilitating the confirmation and mass determination of these worlds. We present the discovery of a hot Jupiter orbiting a rapidly rotating (vsin(i)=35.1±1.0km/s) early F3V-dwarf, HD115447 (TOI-778). The transit signal taken from Sectors 10 and 37 of TESS's initial detection of the exoplanet is combined with follow-up ground-based photometry and velocity measurements taken from Minerva-Australis, TRES, CORALIE and CHIRON to confirm and characterise TOI-778b. A joint analysis of the light curves and the radial velocity measurements yield a mass, radius, and orbital period for TOI-778b of 2.76+0.24−0.23Mjup, 1.370±0.043Rjup and ∼4.63 days, respectively. The planet orbits a bright (V=9.1mag) F3-dwarf with M=1.40±0.05Msun, R=1.70±0.05Rsun, and logg=4.05±0.17. We observed a spectroscopic transit of TOI-778b, which allowed us to derive a sky-projected spin-orbit angle of 18∘±11∘, consistent with an aligned planetary system. This discovery demonstrates the capability of smaller aperture telescopes such as Minerva-Australis to detect the radial velocity signals produced by planets orbiting broad-line, rapidly rotating stars
Selecting appropriate repair materials for concrete
Dr. Michael A. Lacasse: https://orcid.org/0000-0001-7640-3701Dr. Michael A. Lacasse: https://orcid.org/0000-0001-7640-3701Aussi disponible en francais: Le choix des mat\ue9riaux de r\ue9paration pour le b\ue9tonPeer reviewed: NoNRC publication: Ye