NICER - Neutron star Interior Composition ExploreR
ABOUT
This project used the Neutron Star Interior Composition ExploreR (NICER), an X-ray detector on the International Space Station, to study neutron stars. Neutron stars form when massive stars collapse after running out of fuel, and they are the most dense, visible objects in our Universe. Some neutron stars are in binary systems where the lower mass companion is dumping material onto the surface of the neutron star, which can cause instabilities to occur in the form of X-ray bursts. For this specific project, I have been observing a neutron star called SAX J1808.4-3658, which is in a binary system with a brown dwarf. Nearly all of the thousands of observed X-ray bursts are triggered by the unstable burning of helium via the triple-alpha process. In this project, we observed a new kind of burst that is able an order of magnitude fainter than typical bursts and are instead triggered by the unstable burning of hydrogen via the CNO cycle. I collaborated with Tod E. Strohmayer and Peter Bult at NASA's Goddard Space Flight Center. To our knowledge, our paper shows the first, strong evidence of weak, hydrogen-triggered bursts!