Abstract
Magnetars are neutron stars with long spin periods and large spin down rates compared with canonical pulsars. They have ultra strong magnetic fields inferred from the spin-down rates. The observed X-ray luminosity is too large to be explained by the rotational energy loss. It implies that magnetars could be powered by magnetic field decay. Twisted magnetospheric model is the most popular model to explain the behaviors of magnetar, in which trigger bursting activities via magnetic reconnection and the decay of core field could heat up the star. Consequently, magnetars should have higher surface temperature and luminosity than canonical pulsars with similar age. Expanding the sample of magnetars by observations is the key to further our understanding of neutron star evolution.
SGR 0501+4516 is a transient magnetar discovered with BAT of Swift on 2008 Aug 22. My research focuses on the quiescent state of SGR 0501+4516 observed with the Chandra X-ray Observatory. I performed timing and spectral analysis, and found a double-peak pulse profile with phase-average spectroscopy best fitted by the blackbody plus power-law model. The best-fit blackbody temperature is ∼ 0.7 keV, similar to the value during outburst, but the luminosity is lower than that in previous observations. I will further discuss the future works for comparing the data with other magnetars.
Anyone interested is welcome to attend.