The research to be conducted centers on the properties of magnetars - a subclass of neutron stars with magnetic fields of strength in excess of the critical quantum electrodynamic threshold. Here, a series of projects will be carried out aimed at helping answer several questions of current scientific interest. Included are: (1) What is the emission mechanism of magnetars in quiescence? (2) What controls the spectrum of soft gamma ray repeater (a type of magnetar) flares? (3) How is the energy of activity of magnetars tapped in their magnetospheres? And (4) physically, how and why are magnetars different from conventional pulsars? Three general avenues of research will be undertaken, each with associate subprojects. The first is an investigation of resonant scattering in shaping the spectrum of anomalous x-ray pulsar spectra by refining calculations of resonant Compton scattering in ultra strong magnetic fields and the upscattering of thermal surface photons by magnetospheric electrons. In the second, the roles of resonant Compton scattering and photon splitting in the burst spectra of soft gamma-ray repeaters will be explored. This includes developing dispersion and selection rules for photon splitting in ultra strong magnetic fields. Finally, a generalized formalism for stochastic, diffusive, gyroresonant acceleration of particles due to magnetic turbulence superposed upon the global magnetar field structure will be developed. A major emphasis will be determining the shape of the non-thermal distribution and how the maximum energy of acceleration couples to environmental parameters, which will in turn lead to useful observational diagnostics on the emission region. A graduate student will be employed and trained and will be an integral part of the work. This student will also be exposed to undergraduate pedagogy by teaching at least two lectures per year on neutron stars. Undergraduates are expected to contribute as well through small, well defined tasks. Results of this work will be presented to the public through outreach activities at local high schools and through the Houston Astronomical Society.
