How two Cohabiting Magnetic Dynamos explain the Secular Evolution of Cataclysmic Variables

Details How two Cohabiting Magnetic Dynamos explain the Secular Evolution of Cataclysmic Variables How two Cohabiting Magnetic Dynamos explain the Secular Evolution of Cataclysmic Variables

Jul 1997

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1997mnras.289...59z&link_type=abstract

Monthly Notices of the Royal Astronomical Society, Volume 289, Issue 1, pp. 59-65.

Astronomy and Astrophysics

Astronomy

17

Binaries: Close, Stars: Evolution, Stars: Magnetic Fields, Stars: Mass-Loss, Novae, Cataclysmic Variables

Scientific paper

We show how a combination of two alpha-Omega dynamos, one in the convective envelope and the other at the boundary with a slowly rotating radiative core, can nicely explain the secular evolution of cataclysmic variables. The boundary-layer dynamo is dominant when the convective core is small. There it drives magnetic braking which leads to mass-transfer rates of the order of 10^-9M/yr^-1. When the star becomes fully convective, this dynamo switches off. This allows the star to contract inside its Roche lobe creating a period gap at about 3h. The envelope dynamo is dominant at larger periods, while its effects are comparable with gravitational radiation below 3h. It does not, therefore, have much effect on the edges of the period gap. The boundary-layer dynamo must maintain a universal rate of angular momentum loss for all cataclysmic variables if it is to produce the well-defined, observed period gap. The envelope dynamo, on the other hand, may fluctuate considerably and hence give rise to the wide range of mass-transfer rates implied for systems away from the period gap.

Affiliated with

Also associated with

No associations

Rating

How two Cohabiting Magnetic Dynamos explain the Secular Evolution of Cataclysmic Variables 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 How two Cohabiting Magnetic Dynamos explain the Secular Evolution of Cataclysmic Variables, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and How two Cohabiting Magnetic Dynamos explain the Secular Evolution of Cataclysmic Variables will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1415155