Search Publications
ARES I: WASP-76 b, A Tale of Two HST Spectra
Drossart, Pierre; Blain, Doriann; Beaulieu, Jean-Philippe +25 more
We analyze the transmission and emission spectra of the ultra-hot Jupiter WASP-76 b, observed with the G141 grism of the Hubble Space Telescope's (HST) Wide Field Camera 3 (WFC3). We reduce and fit the raw data for each observation using the open-source software Iraclis before performing a fully Bayesian retrieval using the publicly available anal…
The Herschel view of the dense core population in the Ophiuchus molecular cloud
André, Ph.; Arzoumanian, D.; Könyves, V. +15 more
Context. Herschel observations of nearby clouds in the Gould Belt support a paradigm for low-mass star formation, starting with the generation of molecular filaments, followed by filament fragmentation, and the concentration of mass into self-gravitating prestellar cores. In the case of the Ophiuchus molecular complex, a rich star formation activi…
Perpendicular Transport of Energetic Particles in Magnetic Turbulence
Shalchi, Andreas
Scientists have explored how energetic particles such as solar energetic particles and cosmic rays move through a magnetized plasma such as the interplanetary and interstellar medium since more than five decades. From a theoretical point of view, this topic is difficult because the particles experience complicated interactions with turbulent magne…
The Pristine Inner Galaxy Survey (PIGS) I: tracing the kinematics of metal-poor stars in the Galactic bulge
Schultheis, M.; Lardo, C.; Sestito, F. +20 more
Our Galaxy is known to contain a central boxy/peanut-shaped bulge, yet the importance of a classical, pressure-supported component within the central part of the Milky Way is still being debated. It should be most visible at low metallicity, a regime that has not yet been studied in detail. Using metallicity-sensitive narrow-band photometry, the P…
Identical or fraternal twins? The chemical homogeneity of wide binaries from Gaia DR2
Ting, Yuan-Sen; Hawkins, Keith; Lucey, Madeline +7 more
One of the high-level goals of Galactic archaeology is chemical tagging of stars across the Milky Way to piece together its assembly history. For this to work, stars born together must be uniquely chemically homogeneous. Wide binary systems are an important laboratory to test this underlying assumption. Here, we present the detailed chemical abund…
Two Ultra-faint Milky Way Stellar Systems Discovered in Early Data from the DECam Local Volume Exploration Survey
Bechtol, K.; Zenteno, A.; Allam, S. +56 more
We report the discovery of two ultra-faint stellar systems found in early data from the DECam Local Volume Exploration survey (DELVE). The first system, Centaurus I (DELVE J1238-4054), is identified as a resolved overdensity of old and metal-poor stars with a heliocentric distance of ${\text{}}{D}_{\odot }={116.3}_{-0.6}^{+0.6}\,\mathrm{kpc}$ , a …
Relation of X-ray activity and rotation in M dwarfs and predicted time-evolution of the X-ray luminosity
Scholz, A.; Stelzer, B.; Covey, K. R. +3 more
The relation of activity to rotation in M dwarfs is of high astrophysical interest because it provides observational evidence of the stellar dynamo, which is poorly understood for low-mass stars, especially in the fully convective regime. Previous studies have shown that the relation of X-ray activity to rotation consists of two different regimes:…
ARES. II. Characterizing the Hot Jupiters WASP-127 b, WASP-79 b, and WASP-62b with the Hubble Space Telescope
Drossart, Pierre; Blain, Doriann; Beaulieu, Jean-Philippe +24 more
This paper presents the atmospheric characterization of three large, gaseous planets: WASP-127 b, WASP-79 b, and WASP-62 b. We analyzed spectroscopic data obtained with the G141 grism (1.088-1.68 µm) of the Wide Field Camera 3 on board the Hubble Space Telescope using the Iraclis pipeline and the TauREx3 retrieval code, both of which are pub…
A super-Earth and a sub-Neptune orbiting the bright, quiet M3 dwarf TOI-1266
Watson, A. M.; Bouchy, F.; Queloz, D. +70 more
We report the discovery and characterisation of a super-Earth and a sub-Neptune transiting the bright (K = 8.8), quiet, and nearby (37 pc) M3V dwarf TOI-1266. We validate the planetary nature of TOI-1266 b and c using four sectors of TESS photometry and data from the newly-commissioned 1-m SAINT-EX telescope located in San Pedro Mártir (México). W…
Not all stars form in clusters - Gaia-DR2 uncovers the origin of OB associations
Kruijssen, J. M. Diederik; Rix, Hans-Walter; Ward, Jacob L.
Historically, it has often been asserted that most stars form in compact clusters. In this scenario, present-day gravitationally unbound OB associations are the result of the expansion of initially gravitationally bound star clusters. However, this paradigm is inconsistent with recent results, both theoretical and observational, that instead favou…