to the energy range of the Chandra detector. The other three curves correspond to the energy ranges of the BeppoSAX detectors. The magnetic inclination and viewing angles are assumed to be $65^\circ $ and $82^\circ $.\[fig:f5\]]{}

![image](f6_3){width="110mm"}

[Fig. 6. Comparison of expected spectral indices with the observed data. The magnetic inclination and viewing angles are assumed to be $65^\circ $ and $82^\circ $ for the Crab pulsar. The observed data are taken from Massaro et al. (2000) and Weisskopf (2002).\[fig:f6\]]{}

THE PHASE-RESOLVED SPECTRA OF THE GEMINGA PULSAR
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Fierro et al. (1998) have shown the observed light curve and phase-resolved spectra of high-energy $\gamma$-rays of Geminga pulsar detected by EGRET. The observed pulse profile by EGRET indicates that the phase separation is $0.49\pm 0.05$. In order to obtain the observed phase-resolved spectra, Fierro et al. (1998) divided Geminga pulsar phase into 8 parts: leading wing 1 (LW1), peak 1 (P1), trailing wing 1 (TW1), bridge, leading wing 2 (LW2), peak 2 (P2), trailing wing 2 (TW2) and offpulse (OP). The phase intervals widths of all these parts are 0.11, 0.09, 0.11, 0.15, 0.13, 0.13, 0.08 and 0.21 respectively. They have obtained the spectra for these different phase intervals and shown 