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arXiv · 1009.1279

Search for High-Energy Gamma-ray Emission from an Anomalous X-ray Pulsar, 4U 0142+61

Sinem Sasmaz Mus·Ersin Gogus
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Abstract

Until 2004, Anomalous X-ray Pulsars (AXPs) were known as strong emitters of soft X-rays only (< 10 keV). The discovery of hard X-ray component from AXPs provided important insight about their emission properties while it posed a serious challenge to explain its origin. The physical mechanism of the hard emission component has still not been fully resolved. We investigate the high-energy gamma-ray properties of the brightest AXP, 4U 0142+61 using data collected with the Large Area Telescope (LAT) on board Fermi Gamma-ray Space Telescope to establish the spectral behavior of the source on a very broad energy span and search for pulsed emission. Here, we present our results of detailed search for the persistent and pulsed high-energy gamma-ray emission from 4U 0142+61 which result in no significant detection. However, we obtain upper limits to the persistent high-energy gamma-ray emission flux which helps us to constrain existing physical models.

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Sinem Sasmaz Mus, Ersin Gogus. 2010-09-07. Search for High-Energy Gamma-ray Emission from an Anomalous X-ray Pulsar, 4U 0142+61. https://doi.org/10.1088/0004-637x/723/1/100

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