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

• Main Authors: Jason Hung Kit Wu, Chung Yue Hui, Regina Hsiu Hui Huang, Albert Kwok Hing Kong, Kwong Sang Cheng, Jumpei Takata, Pak Hin Thomas Tam, Eric Man Ho Wu, Joe Liu
• Format: Article
• Language: English
• Published: Korean Space Science Society (KSSS) 2013-06-01
• Series: Journal of Astronomy and Space Sciences
• Subjects: pulsars; gamma-rays
• Online Access: http://ocean.kisti.re.kr/downfile/volume/kosss/OJOOBS/2013/v30n2/OJOOBS_2013_v30n2_83.pdf
• ISSN: 2093-5587; 2093-1409

Anomalous X-ray pulsars (AXPs) are thought to be magnetars which are young isolated neutron stars with extremely strong magnetic fields of >1014 Gauss. 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 γ-ray pulsations above 200 MeV from the AXP, 1E 2259+586, which puts the current theoretical models of γ-ray emission mechanisms of magnetars into challenge. We speculate that the high-energy γ-rays originate from the outer magnetosphere of the magnetar.