Related papers: Magnetic complexity as an explanation for bimodal …
Observations of young open clusters show a bimodal distribution of rotation periods that has been difficult to explain with existing stellar spin-down models. Detailed MHD stellar wind simulations have demonstrated that surface magnetic…
This study examines the relationship between magnetic field complexity and mass and angular momentum losses. Observations of open clusters have revealed a bimodal distribution of the rotation periods of solar-like stars that has proven…
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…
Since their formation, stars slow down their rotation rates by the removal of angular momentum from their surfaces, e.g. via stellar winds. Despite the complexity of the processes involved, a traditional model, where the removal of angular…
The concentration of magnetic flux near the poles of rapidly rotating cool stars has been recently proposed as an alternative mechanism to dynamo saturation in order to explain the saturation of angular momentum loss. In this work we study…
This paper introduces a new empirical model for the rotational evolution of Sun-like stars -- those with surface convection zones and non-convective interior regions. Previous models do not match the morphology of observed (rotation…
We use a luminous fast magnetic rotator model to analyze the influence of a magnetic field on the linear waves induced in the wind of a massive star by the radiative instability. We show that a twisted magnetic field can drive a strong wind…
Observations of young open clusters show a bimodal distribution of stellar rotation. Sun-like stars in those clusters group into two main sub-populations of fast and slow rotators. Beyond an age of about 500 Myrs, the two populations…
Angular Momentum Loss is important for understanding astrophysical phenomena such as stellar rotation, magnetic activity, close binaries, and cataclysmic variables. Magnetic breaking is the dominant mechanism in the spin down of young…
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…
Two magnetic braking models are implemented in MESA for use in the MIST stellar model grids. Stars less than about 1.3 $M_{\odot}$ are observed to spin down over time through interaction with their magnetized stellar winds (i.e., magnetic…
Magnetic activity and rotation are known to be intimately linked for low-mass stars. Understanding rotation evolution over the stellar lifetime is therefore an important goal within stellar astrophysics. In recent years, there has been…
Observations of chromospheric and coronal emissions from various solar-type stars show that the stellar magnetic activity varies with the rotation rates of the stars. The faster the star rotates, its magnetic activity gets stronger but…
Rotation has a number of important effects on the evolution of stars. It decreases the surface gravity, causes enhanced mass loss and leads to surface abundance anomalies of various chemical isotopes. We have adapted the Cambridge stellar…
Spectropolarimetric observations show that many low-mass stars possess large-scale poloidal magnetic fields with considerable dipole component, which in some cases exhibit temporal dynamics - cycles or reversals. Although it is widely…
Early-type stars show a bimodal distribution of magnetic field strengths, with some showing very strong fields ($\gtrsim 1\,\mathrm{kG}$) and others very weak fields ($\lesssim 10\,\mathrm{G}$). Recently, we proposed that this reflects the…
Stellar spin is one of the fundamental quantities that characterize a star itself and its planetary system. Nevertheless, stellar spin-down mechanisms in protostellar and pre-main-sequence stellar phases have been a long-standing problem in…
A knowledge of stellar ages is crucial for our understanding of many astrophysical phenomena, and yet ages can be difficult to determine. As they become older, stars lose mass and angular momentum, resulting in an observed slowdown in…
Magnetic fields at the surface of a few early-type stars have been directly detected. These fields have magnitudes between a few hundred G up to a few kG. In one case, evidence of magnetic braking has been found. We investigate the effects…
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…