Overview of the physics in the accretion column
Abstract
This talk discusses the current efforts to model the wide array of physical processes that are important when plasma accretes onto the surface of a highly magnetic neutron star. Broad non-thermal power law X-ray continua are observed that can be modeled by Comptonization of bremsstrahlung, cyclotron, and black body contributions. Cyclotron resonance absorption lines are observed, cast against these broad continua, yielding measurements of the magnetic field strengths. Observations show that in some sources the cyclotron line energies can vary with observed luminosity. This observation has lead to significant debate regarding aspects of the cyclotron line formation process. Multiple groups are currently working on modeling the physical processes that affect the behavior of the plasmas, the formation of the X-ray continuum, and the formation of the cyclotron lines. New analysis tools are becoming available to help interpret observations of these systems. In particular, observations by Suzaku and NuSTAR of the X-ray spectra of these binary systems are advancing our searches for the cyclotron lines and our understanding of the physical processes that contribute to the X-ray continuum formation.
- Publication:
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AAS/High Energy Astrophysics Division #15
- Pub Date:
- April 2016
- Bibcode:
- 2016HEAD...1520101W