Related papers: Protostellar spin-up and fast rotator formation th…
Major photometric monitoring campaigns of star-forming regions in the past decade have provided rich rotation period distributions of pre-main-sequence stars. The rotation periods span more than an order of magnitude in period, with most…
We present simulation results for the formation and long-term evolution of a primordial protostellar disk harbored by a first star. Using a 2+1D nonaxisymmetric thin disk numerical simulation, together with a barotropic relation for the…
The first stars are known to form in primordial gas, either in minihalos with about $10^6$~M$_\odot$ or so-called atomic cooling halos of about $10^8$~M$_\odot$. Simulations have shown that gravitational collapse and disk formation in…
Recent observations uncover various phenomena around the protostar such as misalignment between the outflow and magnetic field, precession of the jet, and time variability of the ejected clumps, whose origins are under debate. We perform a…
Forming massive stars launch outflows of magnetic origin, which in fact serve as a marker for finding sites of massive star formation. However, both the theoretical and observational study of the mechanisms that intervene in the formation…
The presence of gaseous giant planets whose orbits lie in extreme proximity to their host stars ("hot Jupiters"), can largely be accounted for by planetary migration, associated with viscous evolution of proto-planetary nebulae. Recently,…
Isolated low-mass stars are formed, in the standard picture, from the collapse of dense cores condensed out of strongly magnetized molecular clouds. The dynamically collapsing inflow traps nearly half of the critical magnetic flux needed…
Many stars are in binaries or higher-order multiple stellar systems. Although in recent years a large number of binaries have been proven to host exoplanets, how planet formation proceeds in multiple stellar systems has not been studied…
The early pre-main sequence phase during which they are still likely surrounded by an accretion disk represents a puzzling stage of the rotational evolution of solar-mass stars. While they are still accreting and contracting they do not…
The dominant mechanism for generating free-floating planets has so far remained elusive. One suggested mechanism is that planets are ejected from planetary systems due to planet-planet interactions. However, instability around a single star…
A viable solution to the origin of close binary systems, unaccounted for in recent theories, is presented. Fragmentation, occurring at the end of the secondary collapse phase (during which molecular hydrogen is dissociating), can form…
We study rapidly accreting, gravitationally unstable disks with a series of global, three dimensional, numerical experiments using the code ORION. In this paper we conduct a numerical parameter study focused on protostellar disks, and show…
The formation and early evolution of circumstellar discs often occurs within dense, newborn stellar clusters. For the first time, we apply the moving-mesh code AREPO, to circumstellar discs in 3-D, focusing on disc-disc interactions that…
Context: The principal mechanism by which brown dwarfs form, and its relation to the formation of higher-mass (i.e. hydrogen-burning) stars, is poorly understood. Aims: We advocate a new model for the formation of brown dwarfs. Methods: In…
An investigation is made of disk accretion of matter onto a rotating star with an aligned dipole magnetic field. A new aspect of this work is that when the angular velocity of the star and disk differ substantially we argue that the $\bf B$…
The aim of this work is to study the impact of a binary companion on the evolution of two-planet systems during both the type-II migration phase and their long-term evolution after the dissipation of the protoplanetary disk. We use the…
The detailed structure of core-collapse supernova progenitors is crucial for studying supernova explosion engines and the corresponding multimessenger signals. In this paper, we investigate the influence of stellar rotation on binary…
The spin-down of Be stars due to angular momentum transport from star to disc has been considered. This has been prompted by empirical studies of observed optical and IR line profile studies indicating that the disc is rotating in a…
The past decade has seen a revolution in our understanding of protoplanetary disk evolution and planet formation in single star systems. However, the majority of solar-type stars form in binary systems, so the impact of binary companions on…
The dominant mechanism forming multiple stellar systems in the high-mass regime (M$_\ast \gtrsim $ 8 $M_{\odot}$) remained unknown because direct imaging of multiple protostellar systems at early phases of high-mass star formation is very…