Search Publications
Occurrence rates of planets orbiting M Stars: applying ABC to Kepler DR25, Gaia DR2, and 2MASS data
Terrien, Ryan; Ford, Eric B.; Hsu, Danley C.
We present robust planet occurrence rates for Kepler planet candidates around M stars for planet radii Rp = 0.5-4 R⊕ and orbital periods P = 0.5-256 d using the approximate Bayesian computation technique. This work incorporates the final Kepler DR25 planet candidate catalogue and data products and augments them with updated s…
ALMA and ROSINA detections of phosphorus-bearing molecules: the interstellar thread between star-forming regions and comets
Altwegg, K.; Balsiger, H.; Berthelier, J. J. +20 more
To understand how phosphorus (P)-bearing molecules are formed in star-forming regions, we have analysed the Atacama Large Millimeter/Submillimeter Array (ALMA) observations of PN and PO towards the massive star-forming region AFGL 5142, combined with a new analysis of the data of the comet 67P/Churyumov-Gerasimenko taken with the Rosetta Orbiter S…
A Pair of TESS Planets Spanning the Radius Valley around the Nearby Mid-M Dwarf LTT 3780
López-Morales, Mercedes; Latham, David W.; Quinn, Samuel N. +84 more
We present the confirmation of two new planets transiting the nearby mid-M dwarf LTT 3780 (TIC 36724087, TOI-732, V = 13.07, Ks = 8.204, Rs = 0.374 R⊙, Ms = 0.401 M⊙, d = 22 pc). The two planet candidates are identified in a single Transiting Exoplanet Survey Satellite sector and validated wit…
Keck/NIRC2 L'-band Imaging of Jovian-mass Accreting Protoplanets around PDS 70
Baranec, Christoph; Jensen-Clem, Rebecca; Duchêne, Gaspard +42 more
We present L'-band imaging of the PDS 70 planetary system with Keck/NIRC2 using the new infrared pyramid wave front sensor. We detected both PDS 70 b and c in our images, as well as the front rim of the circumstellar disk. After subtracting off a model of the disk, we measured the astrometry and photometry of both planets. Placing priors based on …
TOI-1338: TESS' First Transiting Circumbinary Planet
Trifonov, Trifon; Kostov, Veselin B.; Torres, Guillermo +65 more
We report the detection of the first circumbinary planet (CBP) found by Transiting Exoplanet Survey Satellite (TESS). The target, a known eclipsing binary, was observed in sectors 1 through 12 at 30 minute cadence and in sectors 4 through 12 at 2 minute cadence. It consists of two stars with masses of 1.1 M⊙ and 0.3 M⊙ on a s…
Evidence for Initial Mass Function Variation in Massive Early-Type Galaxies
Smith, Russell J.
The initial mass function (IMF), describing the distribution of birth masses of stars, plays a pivotal role in establishing the observable properties of galaxies. This article reviews the evidence for variation in the IMF of massive early-type galaxies (ETGs), especially from spectroscopic studies and from dynamical and gravitational lensing measu…
Diverse properties of Ly α emission in low-redshift compact star-forming galaxies with extremely high [O III]/[O II] ratios
Schaerer, D.; Thuan, T. X.; Izotov, Y. I. +5 more
We present observations with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope of eight compact star-forming galaxies at redshifts z = 0.02811-0.06540, with low oxygen abundances 12 + log(O/H) = 7.43-7.82 and extremely high emission-line flux ratios O32 = [O III] λ5007/[O II] λ3727 ∼ 22-39, aiming to study the propertie…
Atmospheric regimes and trends on exoplanets and brown dwarfs
Zhang, Xi
A planetary atmosphere is the outer gas layer of a planet. Besides its scientific significance among the first and most accessible planetary layers observed from space, it is closely connected with planetary formation and evolution, surface and interior processes, and habitability of planets. Current theories of planetary atmospheres were primaril…
The ARCiS framework for exoplanet atmospheres. Modelling philosophy and retrieval
Helling, Christiane; Min, Michiel; Ormel, Chris W. +2 more
Aims: We present ARCiS, a novel code for the analysis of exoplanet transmission and emission spectra. The aim of the modelling framework is to provide a tool able to link observations to physical models of exoplanet atmospheres.
Methods: The modelling philosophy chosen in this paper is to use physical and chemical models to constrain cer…
Strong biases in retrieved atmospheric composition caused by day-night chemical heterogeneities
Parmentier, Vivien; Leconte, Jérémy; Pluriel, William +1 more
Most planets currently amenable to transit spectroscopy are close enough to their host stars to exhibit a relatively strong day to night temperature gradient. For hot planets this leads to a chemical composition dichotomy between the two hemispheres. In the extreme case of ultra-hot Jupiters, some species, such as molecular hydrogen and water, are…