Related papers: Evidence for Cluster to Cluster Variations in Low-…
Rotational evolution in young stars is described by pMS evolutionary tracks including rotation, conservation of angular momentum (AM), and simulations of disk-locking (DL). By assuming that DL is the regulation mechanism for the stellar…
We investigate the rotational evolution of solar-like stars with a focus on the internal angular momentum transport processes. The double zone model, in which the star's radiative core and convective envelope are assumed to rotate as solid…
Rotation period measurements of low-mass stars show that the spin distributions in young clusters do not exhibit the spin-up expected due to contraction, during the phase when a large fraction of stars are still surrounded by accretion…
Modeling the rotation history of solar-type stars is still an unsolved problem in modern astrophysics. One of the main challenges is to explain the dispersion in the distribution of stellar rotation rate for young stars. Previous works have…
Young star clusters can inherit bulk rotation from the molecular clouds from which they have formed. This rotation can affect the long-term evolution of a star cluster and its constituent stellar populations. In this study, we aim to…
Both simulations and observations indicate that stars form in filamentary, hierarchically clustered associations, most of which disperse into their galactic field once feedback destroys their parent clouds. However, during their early…
Context. Using asteroseismic techniques, it has recently become possible to probe the internal rotation profile of low-mass (~1.1-1.5 Msun) subgiant and red giant stars. Under the assumption of local angular momentum conservation, the core…
We have determined new rotation periods for 404 stars in the Orion Nebula Cluster using the Wide Field Imager attached to the MPG/ESO 2.2 m telescope on La Silla, Chile. Mass estimates are available for 335 of these and most have M < 0.3…
The process that leads to the formation and early evolution of low-mass stars is in a broad sense well understood theoretically and carefully traced observationally. The largest uncertainties in this framework reside in the poorly known…
Stellar encounters potentially affect the evolution of the protoplanetary discs in the Orion Nebula Cluster (ONC). However, the role of encounters in other cluster environments is less known. We investigate the effect of the…
The evolution of angular momentum is a key to our understanding of star formation and stellar evolution. The rotational evolution of solar-mass stars is mostly controlled by magnetic interaction with the circumstellar disc and angular…
Observational and theoretical investigations provide evidence for non-uniform spot and magnetic flux distributions on rapidly rotating stars, which have a significant impact on their angular momentum loss rate through magnetised winds.…
We present the first "combined stellar structure and atmosphere models" (CoStar) for massive stars, which consistently treat the entire mass loosing star from the center out to the asymptotic wind velocity. The models use up-to-date input…
Young and rapidly rotating stars are known for intense, dynamo generated magnetic fields. Spectropolarimetric observations of those stars in precisely aged clusters are key input for gyrochronology and magnetochronology. We use ZDI maps of…
Angular momentum plays a crucial role in the formation of stars and planets. It has long been noticed that parcels of gas in molecular clouds need to reduce their specific angular momentum by 6 to 7 orders of magnitude to participate in the…
The distribution of angular momentum of planets and their host stars provides important information on the formation and evolution of the planetary system. However, mysteries still remain, partly due to bias and uncertainty of the current…
Context. Very low-mass (VLM) stars and brown dwarfs (BDs) present a different rotational behaviour from their solar mass counter-parts. Aims. We investigate the rotational evolution of young VLM stars and BDs using Monte Carlo simulations…
(Abridged) The formation and evolution of star cluster populations are related to the galactic environment. Cluster formation is governed by processes acting on galactic scales, and star cluster disruption is driven by the tidal field. In…
Aims: We study the acceleration of the stellar winds of rapidly rotating low mass stars and the transition between the slow magnetic rotator and fast magnetic rotator regimes. We aim to understand the properties of stellar winds in the fast…
Observations of PMS star rotation periods reveal slow rotators in young clusters of various ages, indicating that angular momentum is somehow removed from these rotating masses. The mechanism by which spin-up is regulated as young stars…