Search Publications
Internal motions in OB associations with Gaia DR2
Melnik, A. M.; Dambis, A. K.
We study the motions inside 28 OB associations with the use of Gaia DR2 proper motions. The average velocity dispersion calculated for 28 OB associations including more than 20 stars with Gaia DR2 proper motion is σV = 4.5 km s-1. The median virial and stellar masses of OB associations are Mvir = 8.9 × 105
The CO-dark molecular gas mass in 30 Doradus
Lebouteiller, Vianney; Lee, Min-Young; Kruijssen, J. M. Diederik +16 more
Determining the efficiency with which gas is converted into stars in galaxies requires an accurate determination of the total reservoir of molecular gas mass. However, despite being the most abundant molecule in the Universe, H2 is challenging to detect through direct observations and indirect methods have to be used to estimate the tot…
Evidence for metallicity-dependent spin evolution in the Kepler field
Amard, Louis; Roquette, Julia; Matt, Sean P.
A curious rotation period distribution in the colour-magnitude-period diagram (CMPD) of the Kepler field was recently revealed, thanks to data from Gaia and Kepler spacecraft. It was found that redder and brighter stars are spinning slower than the rest of the main sequence. On the theoretical side, it was demonstrated that metallicity should affe…
TESS observations of Be stars: a new interpretation
Balona, L. A.; Ozuyar, D.
Light curves of 57 classical Be stars in TESS sectors 1-15 are examined. In most Be stars, the periodogram shows groups at a fundamental and one or more harmonics, which we attribute to rotation. In about 40 per cent of the stars, the group is just a single narrow or slightly broadened peak. In about 30 per cent, it consists of a multiple, closely…
Predicting accreted satellite galaxy masses and accretion redshifts based on globular cluster orbits in the E-MOSAICS simulations
Trujillo-Gomez, Sebastian; Crain, Robert A.; Kruijssen, J. M. D. +4 more
The ages and metallicities of globular clusters (GCs) are known to be powerful tracers of the properties of their progenitor galaxies, enabling their use in determining the merger histories of galaxies. However, while useful in separating GCs into individual accretion events, the orbits of GC groups themselves have received less attention as probe…
Simultaneous TESS and NGTS transit observations of WASP-166 b
Wheatley, Peter J.; Bayliss, Daniel; Casewell, Sarah L. +21 more
We observed a transit of WASP-166 b using nine Next Generation Transit Survey (NGTS) telescopes simultaneously with the Transiting Exoplanet Survey Satellite (TESS) observations of the same transit. We achieved a photometric precision of 152 ppm per 30 min with the nine NGTS telescopes combined, matching the precision reached by TESS for the trans…
Jet feedback and the photon underproduction crisis in SIMBA
Davé, Romeel; Christiansen, Jacob F.; Sorini, Daniele +1 more
We examine the impact of black hole jet feedback on the properties of the low-redshift intergalactic medium (IGM) in the SIMBA simulation, with a focus on the Lyα forest mean flux decrement DA. Without jet feedback, we confirm the photon underproduction crisis (PUC) in which ΓH I at $z$ = 0 must be increased by 6 times over t…
Dynamical orbital classification of selected N-rich stars with Gaia Data Release 2 astrometry
Fernández-Trincado, José G.; Ortigoza-Urdaneta, Mario; Moreno, Edmundo +4 more
We have used the galaxy modelling algorithm GRAVPOT16, to explore the most probable orbital elements of a sample of 64 selected N-rich stars across the Milky Way. We use the newly measured proper motions from Gaia Data Release 2 with existing line-of-sight velocities from the second generation of the Apache Point Observatory Galactic Evolution Exp…
TICs 167692429 and 220397947: the first compact hierarchical triple stars discovered with TESS
Mitnyan, T.; Pál, A.; Klagyivik, P. +5 more
We report the discovery and complex analyses of the first two compact hierarchical triple star systems discovered with TESS in or near its southern continuous viewing zone during Year 1. Both TICs 167692429 and 220397947 were previously unknown eclipsing binaries, and the presence of a third companion star was inferred from eclipse timing variatio…
WASP-52b. The effect of star-spot correction on atmospheric retrievals
Mikal-Evans, Thomas; Sing, David K.; López-Morales, Mercedes +13 more
We perform atmospheric retrievals on the full optical to infrared (0.3-5 µ m) transmission spectrum of the inflated hot Jupiter WASP-52b by combining HST/STIS, WFC3 IR, and Spitzer/IRAC observations. As WASP-52 is an active star that shows both out-of-transit photometric variability and star-spot crossings during transits, we account for the…