Search Publications
The vertical structure of debris discs and the impact of gas
Henning, Thomas; Boccaletti, Anthony; Kral, Quentin +10 more
The vertical structure of debris discs provides clues about their dynamical evolution and the collision rate of the unseen planetesimals. Thanks to the ever-increasing angular resolution of contemporary instruments and facilities, we are beginning to constrain the scale height of a handful of debris discs, either at near-infrared or millimeter wav…
A comprehensive analysis of WASP-17b's transmission spectrum from space-based observations
May, E. M.; Wakeford, H. R.; Sing, D. K. +9 more
Due to its 1770 K equilibrium temperature, WASP-17b, a 1.99 RJup, 0.486 MJup exoplanet, sits at the critical juncture between hot and ultra-hot Jupiters. We present its 0.3-5 $\rm{\mu m}$ transmission spectrum, newly obtained with Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) measurements, and, taking advantage of i…
Hidden cooling flows in clusters of galaxies
Fabian, A. C.; Pinto, C.; Ferland, G. J. +3 more
The radiative cooling time of the hot gas at the centres of cool cores in clusters of galaxies drops down to 10 Myr and below. The observed mass cooling rate of such gas is very low, suggesting that active galactic nucleus feedback is very tightly balanced or that the soft X-ray emission from cooling is somehow hidden from view. We use an intrinsi…
Astrometric excess noise in Gaia EDR3 and the search for X-ray binaries
Knigge, C.; Charles, P. A.; Gandhi, P. +6 more
Astrometric noise (ϵ) in excess of parallax and proper motion is a potential signature of orbital wobble (ω) of individual components in binary star systems. The combination of X-ray selection with astrometric noise could then be a powerful tool for robustly isolating accreting binaries in large surveys. Here, we mine the Gaia EDR3 catalogue for G…
Probabilistic classification of X-ray sources applied to Swift-XRT and XMM-Newton catalogs
Godet, Olivier; Tranin, Hugo; Webb, Natalie +1 more
Context. Serendipitous X-ray surveys have proven to be an efficient way to find rare objects, for example tidal disruption events, changing-look active galactic nuclei (AGN), binary quasars, ultraluminous X-ray sources, and intermediate mass black holes. With the advent of very large X-ray surveys, an automated classification of X-ray sources beco…
Effects of Grain Alignment with Magnetic Fields on Grain Growth and the Structure of Dust Aggregates
Hoang, Thiem
Dust grains drift through the interstellar medium and are aligned with the magnetic field. Here we study the effect of grain alignment and motion on grain growth in molecular clouds (MCs). We first discuss the characteristic timescales of alignment of the grain axis of maximum inertia ( $\hat{{\boldsymbol{a}}}$ 1) with its angular momen…
The size-luminosity relation of lensed galaxies at z 6-9 in the Hubble Frontier Fields
Castellano, Marco; Fontana, Adriano; Treu, Tommaso +8 more
We measure the size-luminosity relation of photometrically selected galaxies within the redshift range z ~ 6-9, using galaxies lensed by six foreground Hubble Frontier Fields (HFF) clusters. The power afforded by strong gravitational lensing allows us to observe fainter and smaller galaxies than in blank fields. We select our sample of galaxies an…
Result of the MICROSCOPE weak equivalence principle test
Bergé, Joel; Pernot-Borràs, Martin; Chhun, Ratana +44 more
The space mission MICROSCOPE dedicated to the test of the equivalence principle (EP) operated from April 25, 2016 until the deactivation of the satellite on October 16, 2018. In this analysis we compare the free-fall accelerations (a A and a B) of two test masses in terms of the Eötvös parameter $\eta (\text{A,B})=2\frac{{a}_…
CLEAR: Paschen-β Star Formation Rates and Dust Attenuation of Low-redshift Galaxies
Papovich, Casey; Finkelstein, Steven L.; Cleri, Nikko J. +12 more
We use Paschen-β (Paβ; 1282 nm) observations from the Hubble Space Telescope G141 grism to study the star formation and dust-attenuation properties of a sample of 29 low-redshift (z < 0.287) galaxies in the CANDELS Lyα Emission at Reionization survey. We first compare the nebular attenuation from Paβ/Hα with the stellar attenuation inferred fro…
Investigation of the orbital period and mass relations for W UMa-type contact systems
Poro, A.; Sabbaghian, G.; Madayen, T. +14 more
New relationships between the orbital period and some parameters of W Ursae Majoris (W UMa)-type systems are presented in this study. To investigate the relationships, we calculated the absolute parameters of a sample of 118 systems. For this purpose, we used the parallax values obtained from the Gaia Early Data Release 3 star catalogue for more p…