Research Topics

I worked with Dr. Emrah Kalemci as a Marie Curie graduate researcher. I learned how to do data analysis of the SPI detector aboard the INTEGRAL satellite. We looked for the 2.2 MeV neutron capture line from an accreting neutron star, hoping to put a constraint on the neutron star equation of state. The limited amount of useable data and high background noise prevented us from detecting the line, but we were able to put an upper limit on the flux of the source. Our paper was published in the Astrophysical Journal.

Dr. Unal Ertan was my Ph.D. advisor and with him I worked on several projects:

We investigated the optical and infrared fluxes of five persistent Anomalous X-ray Pulsars and showed that an irradiated accretion disk with reasonable disk parameters can account for their observed flux values. Our paper was published in the Astrophysical Journal Letters.

We modeled the X-ray light curves of transient AXP and SGRs with active fallback disks. We reproduced the observed flux data for four sources using a narrow range of parameters for viscosity, irradiation parameter and critical temperature. Our results were published in the Astrophysical Journal.

We are working on modeling the luminosity, period and period derivative evolution of XDINS with an active fallback disk. We can reproduce the observed period and period derivative values of all XDINS for which P and Pdot is measured. The parameters for the model agree with earlier results.

With Dr. Ertan and Prof. Alpar, we studied the X-ray luminosity, period and period derivative of SGR 0418+5729 in the context of an accreting fallback disk. The extremely low upper limit on the Pdot contradicts the magnetar theory but we were able to show that an active disk with a non-magnetar dipole field can produce the observed values. Our paper was published in the Astrophysical Journal Letters.