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abstract: 'We suggest that some observational features of high-energy radiation from pulsars should be explained in terms of three dimensional geometric models, e.g. the phase-resolved X-ray and $\gamma$-ray spectra and the energy dependent light curves from various pulsars. In this paper, we present a three dimensional pulsar outer-magnetospheric gap model to explain these observational features. The outer-magnetospheric gap is proposed to form near the null charged surface and extend toward the light cylinder. The other two geometric dimensions of the outer-magnetospheric gap, i.e. the vertical size and the azimuthal extension can be determined self-consistently. We apply this model to explain the observed phase-dependent spectra and the energy-dependent light curves of various pulsars.'
address: 'Department of Physics, University of Hong Kong, Hong Kong, China'
author:
- 'K.S. Cheng'
title: 'HIGH-ENERGY RADIATION FROM PULSARS : A THREE DIMENSIONAL MODEL APPROACH'
---

INTRODUCTION
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The non-thermal high-energy radiation from rotation-powered pulsars is believed to be emitted from their magnetosphere. In the past one decade, there has been a lot of progress in detecting and understanding high-energy radiation from rotation powered pulsars. In particular, the X-ray and $\gamma$-ray data obtained by the satellite observatories ROSAT, ASCA, RXTE, BeppoSAX, RXTE, CGRO, Chandra and XMM-Newton 