Related papers: A He3 driven instability near the fully convective…
The origin of rapid rotation in massive stars remains debated, although binary interactions are now often advocated as a cause. However, the broad and shallow lines in the spectra of fast rotators make direct detection of binarity…
Stars may be assembled in large growth spurts, however the evidence for this hypothesis is circumstantial. Directly studying the accretion at the earliest phases of stellar growth is challenging because young stars are deeply embedded in…
Stars between two and three solar masses rotate rapidly on the main sequence, and the detection of slow core and surface rotation in the core-helium burning phase for these stars places strong constraints on their angular momentum transport…
A 5-night asteroseismic observation of the F8V star HD 203608 was conducted in August 2006 with HARPS, followed by an analysis of the data, and a preliminary modeling of the star (Mosser et al. 2008). The stellar parameters were…
Within the convection zone of a rotating star, the presence of the Coriolis force stabilizes long-wavelength convective modes. These modes, which would have been unstable if the star lacked rotation, are called overstable convective modes…
Stars are likely to form or to be captured in AGN disks. Their mass reaches an equilibrium when their rate of accretion is balanced by that of wind. If the exchanged gas is well mixed with the stellar core, this metabolic process would…
Starburst galaxies are undergoing intense periods of star formation. Understanding the heating and cooling mechanisms in these galaxies can give us insight to the driving mechanisms that fuel the starburst. Molecular emission lines play a…
In 2006 Vega was discovered to display excess near-infrared emission. Surveys now detect this phenomenon for one fifth of main-sequence stars, across various spectral types and ages. The excesses are interpreted as populations of small, hot…
Most stars form in star clusters and stellar associated. To understand the roles of star cluster environments in shaping the dynamical evolution of planetary systems, we carry out direct $N$-body simulations of four planetary systems models…
Aims: The main goal of this study is to perform a sub-arcsecond resolution analysis of the high-mass star formation region G19.61-0.23, both in the continuum and molecular line emission. While the centimeter continuum images will be…
Observed supermassive black holes in the early universe have several proposed formation channels, in part because most of these channels are difficult to probe. One of the more promising channels, the direct collapse of a supermassive star,…
Using zoom-simulations carried out with the adaptive mesh-refinement code RAMSES with a dynamic range of up to $2^{27} \approx 1.34 \times 10^8$ we investigate the accretion profiles around six stars embedded in different environments…
Recently, Jao et al. (2018) discovered a gap in the mid-M dwarfs main sequence revealed by the analysis of Gaia data Release 2. They suggested the feature is linked to the onset of full convection in M dwarfs. Following the announcement of…
Massive stars are progenitors of supernovae, neutron stars and black holes. During the hydrogen-core burning phase their convective cores are the prime drivers of their evolution, but inferences of core masses are subject to unconstrained…
Stars with masses $\gtrsim 4 \times 10^{27}M_{\rm{moose}} \approx 1.1 M_\odot$ have core convection zones during their time on the main sequence. In these moosive stars, convection introduces many uncertainties in stellar modeling. In this…
We demonstrate that a seismic analysis of stars in their earliest evolutionary phases is a powerful method to identify young stars and distinguish their evolutionary states. The early star that is born from the gravitational collapse of a…
We discuss the stability of galactic disks in which the energy of interstellar clouds is gained in encounters with expanding supernova remnants and lost in inelastic collisions. Energy gain and loss processes introduce a phase difference…
Massive star formation requires the accretion of gas at high rate while the star is already bright. Its actual luminosity depends sensitively on the stellar structure. We compute pre-main-sequence tracks for massive and intermediate-mass…
The treatment of convective boundaries during core helium burning is a fundamental problem in stellar evolution calculations. In Paper~I we showed that new asteroseismic observations of these stars imply they have either very large…
We consider experimentally the instability and mass transport of a porous-medium flow in a Hele-Shaw geometry. In an initially stable configuration, a lighter fluid (water) is located over a heavier fluid (propylene glycol). The fluids mix…