1210.5422 (J. H. K. Wu et al.)

Pulsed γ-ray emission from magnetar 1E 2259+586    [PDF]

J. H. K. Wu, C. Y. Hui, R. H. H. Huang, A. K. H. Kong, K. S. Cheng, J. Takata, P. H. T. Tam, E. M. H. Wu, C. -Y. Liu

Anomalous x-ray pulsars (AXPs) are thought to be magnetars which are young isolated neutron stars with extremely strong magnetic fields of > 10^14Gauss. Their tremendous magnetic fields inferred from the spin parameters provide a huge energy reservoir to power the observed x-ray emission. High-energy emission above 0.3 MeV has never been detected despite intensive search. Here, we present the possible Fermi Large Area Telescope (LAT) detection of {\gamma}-ray pulsations above 200 MeV from the AXP, 1E 2259+586, which puts the current theoretical models of {\gamma}-ray emission mechanisms of magnetars into challenge. We speculate that the high-energy {\gamma}-rays originate from the outer magnetosphere of the magnetar.

View original: http://arxiv.org/abs/1210.5422