Research: Project Overview
Neutron stars are the dense, highly magnetized cores of massive stars that are left behind after supernova explosions. A neutron star's strong magnetic field accelerates electrons, creating beams of radiation that emanate from the magnetic poles. In a manner similar to a lighthouse signal, this beam of radiation sweeps across space. If this beam intersects Earth, astronomers can detect a burst of light. Because of this behavior, we call such objects pulsars.
X-ray pulsars are a subclass of pulsars that emit X-ray radiation due to accretion. These pulsars are formed in binary systems where the companion star undergoes mass loss. The expelled matter gravitationally falls towards the pulsar, forming an accretion disk. However, when the infalling matter reaches the pulsar's magnetosphere, the magnetic forces dominate the accretion process. As the gas is confined to the pulsar's dipolar magnetic field, the infalling gas heats up and emits X-rays. The process of magnetic accretion, and the response of matter to magnetic fields that are trillions of times stronger than Earth's, is not well understood.
In order to learn more about magnetic accretion mechanisms, I am studying the geometry and kinematics of the warped accretion disks found in LMC X-4 and SMC X-1. Using joint observations from the NuSTAR and XMM-Newton space telescopes, I can observe a complete precession of the accretion disk and use tomography to model the geometry of the disk during its precession.