Magnetospheres of neutron stars accreting from disks

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5151736

Zylstra, G J

This thesis presents quantitative models of the magnetosphere of a magnetic star surrounded by a thin plasma disk. The model is motivated by the currently accepted picture of many accretion-powered pulsars as strongly magnetic neutron stars accreting from disks. It may also be relevant to the luminous galactic bulge X-ray sources that display quasi-periodic oscillations in intensity. These QPO sources are thought by some to be weakly magnetic neutron stars accreting from disks. In constructing these magnetospheric models, I assume that the magnetic field is static and axisymmetric about the axis of the disk. I also assume that the magnetic field is in force-free equilibrium. The validity of these simplifying assumptions for astrophysical systems is discussed in some detail. The boundary conditions on the magnetic field at the disk have been chosen to mimic the expected electrodynamic interaction between a magnetic neutron star and an accretion disk. These boundary conditions cause the second-order partial differential equation for the magnetic flux function to be non-linear. This equation is solved iteratively using finite-difference techniques on a grid of points covering the volume of the magnetosphere.

• Research Organization: Illinois Univ., Urbana, IL (USA)
• OSTI ID: 5151736
• Country of Publication: United States
• Language: English

Related Subjects

640100* -- Astrophysics & Cosmology
640102 -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCRETION DISKS
ATMOSPHERES
CALCULATION METHODS
COMPUTER CALCULATIONS
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELDS
NEUTRON STARS
STARS
STELLAR ATMOSPHERES
STELLAR MAGNETOSPHERES