Orbital period modulation in close binaries due to cyclic alpha 2-dynamo activity

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

10

Magnetic Fields, Mhd, Stars: Individual: Rs Cvn

Scientific paper

The question is answered whether dynamo-generated magnetic fields are able to produce such quadrupole terms in the gravity potential which can explain the observed cyclic orbital variation of RS CVn stars. We start with spherical dynamo models with outer convection zones but without any differential rotation, i.e. with alpha 2-dynamos which are known as nonoscillating. With the known anisotropic alpha -tensor of rapidly rotating stars the magnetic modes with the lowest dynamo numbers are nonaxisymmetric with a slow azimuthal drift. We also find, however, stable (i.e. with the lowest dynamo number) axisymmetric oscillating modes but only for a very special, highly inhomogeneous alpha -tensor. The dynamo model is a linear one with an arbitrary field amplitude which can be scaled in order to reproduce the observations. The star proves to be as prolate during the maximum of the toroidal field energy and it proves to be as oblate during the maximum of the poloidal field energy. In the time average the influence of the toroidal field dominates and the star is slightly prolate. From the computed temporal variations of the gravitation quadrupole moment a magnetic field of more than 105 G is found in order to produce the period modulation of order 10-5 which has been observed.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Orbital period modulation in close binaries due to cyclic alpha 2-dynamo activity does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Orbital period modulation in close binaries due to cyclic alpha 2-dynamo activity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Orbital period modulation in close binaries due to cyclic alpha 2-dynamo activity will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1311116

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.