Rotation and Magnetic Fields of Solar-Like Stars

Magnetic fields in the formation of sun-like stars.

We report high-angular-resolution measurements of polarized dust emission toward the low-mass protostellar system NGC 1333 IRAS 4A. We show that in this system the observed magnetic field morphology is in agreement with the standard theoretical models of the formation of Sun-like stars in magnetized molecular clouds at scales of a few hundred astronomical units; gravity has overcome magnetic su...

Gravity, Rotation and Magnetic Fields

Magnetic fields are fundamental to the dynamics of both accretion disks and the jets that they often drive. We review the basic physics of these phenomena, the past and current efforts to model them numerically with an emphasis on the jetdisk connection, and the observational constraints on the role of magnetic fields in the jets of active galaxies on all scales.

Solar Magnetic Fields

Rapid Rotation, Active Nests of Convection and Global-scale Flows in Solar-like Stars

In the solar convection zone, rotation couples with intensely turbulent convection to build global-scale flows of differential rotation and meridional circulation. Our sun must have rotated more rapidly in its past, as is suggested by observations of many rapidly rotating young solar-type stars. Here we explore the effects of more rapid rotation on the patterns of convection in such stars and t...

Coronae on solar-like stars

The results of a complete and sensitive X-ray survey of all known stars of spectral type A, F, and G in the immediate solar vicinity with distances less than 13 pc are presented. The X-ray data were obtained primarily from the ROSAT all-sky survey (RASS); those program stars not detected in the RASS data, were subsequently studied in the ROSAT pointed observation program. The detection rate amo...