Abstract
Abstract Magnetars are neutron stars having extreme magnetic field strengths. Study of their emission properties in quiescent state can help understand effects of a strong magnetic field on neutron stars. SGR 0501+4516 is a magnetar that was discovered in 2008 during an outburst, which has recently returned to quiescence. We report its spectral and timing properties measured with new and archival observations from the Chandra X-ray Observatory, XMM-Newton, and Suzaku. We found that the quiescent spectrum is best fit by a power-law plus two blackbody model, with temperatures of kT low ∼ 0.26 keV and kT high ∼ 0.62 keV. We interpret these two blackbody components as emission from a hotspot and the entire surface. The hotspot radius shrunk from 1.4 km to 0.49 km since the outburst, and there was a significant correlation between its area and the X-ray luminosity, which agrees well with the prediction by the twisted magnetosphere model. We applied the two-temperature spectral model to all magnetars in quiescence and found that it could be a common feature among the population. Moreover, the temperature of the cooler blackbody shows a general trend with the magnetar field strength, which supports the simple scenario of heating by magnetic field decay.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
