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On the Spectral Shape of Non-recycled γ-ray Pulsars

Hui, Chung-Yue;Lee, Jongsu

  • Received : 2016.05.05
  • Accepted : 2016.05.27
  • Published : 2016.06.15

Abstract

More than 100 γ−ray pulsars have been discovered by the Fermi Gamma-ray Space Telescope. With a significantly enlarged sample size, it is possible to compare the properties of different classes. Radio-quiet (RQ) γ−ray pulsars form a distinct population, and various studies have shown that the properties of the RQ population can be intrinsically different from those of radio-loud (RL) pulsars. Utilizing these differences, it is possible to further classify the pulsar-like unidentified γ−ray sources into sub-groups. In this study, we suggest the possibility of distinguishing RQ/RL pulsars by their spectral shape. We compute the probabilities of a pulsar to be RQ or RL for a given spectral curvature. This can provide a key to the estimation of the intrinsic fraction of radio-quietness in the γ−ray pulsar population, which can place a tight constraint on the emission geometry.

Keywords

gamma rays;stars;pulsars;genera

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Acknowledgement

Grant : BK21플러스

Supported by : 충남대학교