Search Publications
Chemo-dynamical properties of the Anticenter Stream: a surviving disc fossil from a past satellite interaction.
Laporte, Chervin F. P.; Belokurov, Vasily; Hill, Vanessa +2 more
Using Gaia DR2, we trace the Anticenter Stream (ACS) in various stellar populations across the sky and find that it is kinematically and spatially decoupled from the Monoceros Ring. Using stars from LAMOST and SEGUE, we show that the ACS is systematically more metal-poor than Monoceros by 0.1 dex with indications of a narrower metallicity spread. …
Uncovering a 260 pc wide, 35-Myr-old filamentary relic of star formation
Boffin, Henri M. J.; Jerabkova, Tereza; Beccari, Giacomo
Several recent studies have shown that the Vela OB2 region hosts a complex constellation of sub-populations with ages in the range 10 to 50 Myr. Such populations might represent the best example of the outcome of clustered star formation in giant molecular clouds (GMCs). We use Gaia DR2 data over an area of 40 deg radius around the open cluster Co…
Pulsation among TESS A and B stars and the Maia variables
Balona, L. A.; Ozuyar, D.
Classification of over 50 000 TESS stars in sectors 1-18 has resulted in the detection of 766 pulsating main-sequence B stars as well as over 5000 δ Scuti, 2300 γ Doradus, and 114 roAp candidates. Whereas it has been assumed that high-frequency pulsations among B-type main-sequence stars are confined to the early B-type β Cephei stars, the observa…
Ubiquitous Molecular Outflows in z > 4 Massive, Dusty Galaxies. I. Sample Overview and Clumpy Structure in Molecular Outflows on 500 pc Scales
Gonzalez, Anthony H.; Phadke, Kedar A.; Aravena, Manuel +14 more
Massive galaxy-scale outflows of gas are one of the most commonly invoked mechanisms to regulate the growth and evolution of galaxies throughout the universe. While the gas in outflows spans a large range of temperatures and densities, the cold molecular phase is of particular interest because molecular outflows may be capable of suppressing star …
Current Population Statistics Do Not Favor Photoevaporation over Core-powered Mass Loss as the Dominant Cause of the Exoplanet Radius Gap
Loyd, R. O. Parke; Peacock, Sarah; Richey-Yowell, Tyler +4 more
We search for evidence of the cause of the exoplanet radius gap, I.e., the dearth of planets with radii near 1.8 R⊕. If the cause were photoevaporation, the radius gap should trend with proxies for the early-life high-energy emission of the planet-hosting stars. If, alternatively, the cause were core-powered mass loss, no such trends sh…
ARES. III. Unveiling the Two Faces of KELT-7 b with HST WFC3
Drossart, Pierre; Beaulieu, Jean-Philippe; Changeat, Quentin +24 more
We present the analysis of the hot-Jupiter KELT-7 b using transmission and emission spectroscopy from the Hubble Space Telescope, both taken with the Wide Field Camera 3. Our study uncovers a rich transmission spectrum that is consistent with a cloud-free atmosphere and suggests the presence of H2O and H-. In contrast, the ex…
XMM-Newton campaign on ultraluminous X-ray source NGC 1313 X-1: wind versus state variability
Guainazzi, M.; Fabian, A. C.; Pinto, C. +12 more
Most ultraluminous X-ray sources (ULXs) are thought to be powered by neutron stars and black holes accreting beyond the Eddington limit. If the compact object is a black hole or a neutron star with a magnetic field ≲1012 G, the accretion disc is expected to thicken and launch powerful winds driven by radiation pressure. Evidence of such…
Stellar masses of giant clumps in CANDELS and simulated galaxies using machine learning
Giavalisco, Mauro; Snyder, Gregory; Koekemoer, Anton +12 more
A significant fraction of high redshift star-forming disc galaxies are known to host giant clumps, whose nature and role in galaxy evolution are yet to be understood. In this work, we first present a new method based on neural networks to detect clumps in galaxy images. We use this method to detect clumps in the rest-frame optical and UV images of…
Chasing Accreted Structures within Gaia DR2 Using Deep Learning
Lisanti, Mariangela; Necib, Lina; Cohen, Timothy +3 more
In previous work, we developed a deep neural network classifier that only relies on phase-space information to obtain a catalog of accreted stars based on the second data release of Gaia (DR2). In this paper, we apply two clustering algorithms to identify velocity substructure within this catalog. We focus on the subset of stars with line-of-sight…
TOI-677b: A Warm Jupiter (P = 11.2 days) on an Eccentric Orbit Transiting a Late F-type Star
Trifonov, Trifon; Henning, Thomas; Barclay, Thomas +46 more
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 ${\text{}}{M}_{{\text{}}p} = ${1.236}_{-0.067}^{+0.069} ${\text{}}{M}_{{\rm{J}}}, a radius of ${\text{}}{R}_…