Search Publications
Observational constraints on the optical and near-infrared emission from the neutron star-black hole binary merger candidate S190814bv
Covino, S.; D'Avanzo, P.; Campana, S. +151 more
Context. Gravitational wave (GW) astronomy has rapidly reached maturity, becoming a fundamental observing window for modern astrophysics. The coalescences of a few tens of black hole (BH) binaries have been detected, while the number of events possibly including a neutron star (NS) is still limited to a few. On 2019 August 14, the LIGO and Virgo i…
The origin of the escape of Lyman α and ionizing photons in Lyman continuum emitters
Chisholm, J.; Schaerer, D.; Verhamme, A. +2 more
Context. Identifying the physical mechanisms driving the escape of Lyman continuum (LyC) photons is crucial for the search of Lyman continuum emitter (LCE) candidates.
Aims: To understand the physical properties involved in the leakage of LyC photons, we investigate the connection between the H I covering fraction, H I velocity width, the Lym…
Discovery of a nearby 1700 km s-1 star ejected from the Milky Way by Sgr A*
Lewis, Geraint F.; Boubert, Douglas; Erkal, Denis +18 more
We present the serendipitous discovery of the fastest main-sequence hyper-velocity star (HVS) by the Southern Stellar Stream Spectroscopic Survey (S5). The star S5-HVS1 is a ∼2.35 M⊙ A-type star located at a distance of ∼9 kpc from the Sun and has a heliocentric radial velocity of 1017 ± 2.7 km s^{-1} without any signature of…
A remnant planetary core in the hot-Neptune desert
Latham, David W.; Gandhi, Siddharth; Brogi, Matteo +92 more
The interiors of giant planets remain poorly understood. Even for the planets in the Solar System, difficulties in observation lead to large uncertainties in the properties of planetary cores. Exoplanets that have undergone rare evolutionary processes provide a route to understanding planetary interiors. Planets found in and near the typically bar…
Dynamical traceback age of the β Pictoris moving group
Miret-Roig, N.; Bouy, H.; Figueras, F. +7 more
Context. The β Pictoris moving group is one of the most well-known young associations in the solar neighbourhood and several members are known to host circumstellar discs, planets, and comets. Measuring its age precisely is essential to the study of several astrophysical processes, such as planet formation and disc evolution, which are strongly ag…
Is HR 6819 a triple system containing a black hole?. An alternative explanation
Shenar, T.; Sana, H.; Hawcroft, C. +10 more
Context. HR 6819 was recently proposed to be a triple system consisting of an inner B-type giant plus black hole (BH) binary with an orbital period of 40 d and an outer Be tertiary. This interpretation is mainly based on two inferences: that the emission attributed to the outer Be star is stationary and that the inner star, which is used as mass c…
The diversity and variability of star formation histories in models of galaxy evolution
Somerville, Rachel S.; Genel, Shy; Hernquist, Lars +10 more
Understanding the variability of galaxy star formation histories (SFHs) across a range of time-scales provides insight into the underlying physical processes that regulate star formation within galaxies. We compile the SFHs of galaxies at z = 0 from an extensive set of models, ranging from cosmological hydrodynamical simulations (Illustris, Illust…
The Next Generation Virgo Cluster Survey (NGVS). XXX. Ultra-diffuse Galaxies and Their Globular Cluster Systems
Liu, Chengze; Cuillandre, Jean-Charles; Gwyn, S. D. J. +14 more
We present a study of ultra-diffuse galaxies (UDGs) in the Virgo Cluster based on deep imaging from the Next Generation Virgo Cluster Survey. Applying a new definition for the UDG class based on galaxy scaling relations, we define samples of 44 and 26 UDGs using expansive and restrictive selection criteria, respectively. Our UDG sample includes ob…
Driving classical Wolf-Rayet winds: a Γ- and Z-dependent mass-loss
Hamann, W. -R.; Vink, J. S.; Sander, Andreas A. C.
Classical Wolf-Rayet (cWR) stars are at a crucial evolutionary stage for constraining the fates of massive stars. The feedback of these hot, hydrogen-depleted stars dominates their surrounding by tremendous injections of ionizing radiation and kinetic energy. The strength of a Wolf-Rayet (WR) wind decides the eventual mass of its remnant, likely a…
Variability of OB stars from TESS southern Sectors 1-13 and high-resolution IACOB and OWN spectroscopy
Simón-Díaz, S.; Aerts, C.; Castro, N. +6 more
Context. The lack of high-precision long-term continuous photometric data for large samples of stars has impeded the large-scale exploration of pulsational variability in the OB star regime. As a result, the candidates for in-depth asteroseismic modelling have remained limited to a few dozen dwarfs. The TESS nominal space mission has surveyed the …