CAREER: Reflection and reverberation in neutron star low-mass X-ray binaries

Wayne State University, Detroit MI

Investigators

Abstract

This award will enable Professor Edward Cackett at Wayne State University to analyze archival X-ray data and carry out new observations of low-mass X-ray binaries. He will use both timing and spectral information to probe the kinematics and geometry of the inner regions of accretion disks. His procedure involves modeling the reverberation of emission from a corona or boundary layer as it reflects off the inner accretion disk. Models of this process will be constrained by the spectral-dependent time lag of two emission components. The PI has been a key player in applying these techniques to active galactic nuclei and stellar-mass black-hole accretion, and he will extend this work to neutron stars in low-mass X-ray binaries. Neutron stars provide the only way to probe fundamental questions regarding the behavior of matter under the most extreme conditions, with densities at their center being many times nuclear density. This award will facilitate a better measurement of the radius of neutron stars, and it will use neutron stars with low-mass companions as laboratories to study the physical process of accretion, which happens in a wide range of astrophysical contexts. Professor Cackett is actively building an integrated research and education program at Wayne State University. As part of this award, he will develop a program to provide solar telescopes to metropolitan Detroit area high schools to add a hands-on daytime observing aspect to their science curricula. To multiply the effectiveness, he will conduct workshops for high-school teachers and provide sample curricular materials and independent research projects. These workshops will also include a review of all astronomy topics in the high school science standards, with a particular focus on contemporary topics of interest that are associated with the original and creative research funded by this award.