為了研究造成射電脈衝星與射電波段沒有明顯可觀測訊號的中子星兩者不同的可能原因，我們推論出一些的射電訊號不明顯的中子星的磁軸傾角(α，中子星自轉軸和磁軸的夾角)和觀察者的觀察角(ζ，中子星自轉軸和觀察者視線方向的夾角)。針對具有X射線熱輻射的中子星，我們可以經由給定中子星表面的溫度分佈並假設中子星的表面輻射是以黑體輻射的形式描述，進而計算出模擬的光度曲線和光譜。再者，藉著改變模型中的α與ζ參數，並把觀測結果以及我們的計算結果與觀測結果相互比較,可以找出特定具有熱輻射性質的中子星所可能具有的α與ζ範圍。在計算中，我們考慮了廣義相對論造成的光徑彎曲以及重力紅移的效應。我們討論了因為重力、溫度分佈和光線集中效應(包括邊界致暗以及磁場造成的光線集中)對於光度曲線與光譜造成的影響。此外，我們的結果顯示，沒有明顯的證據支持射電脈衝星與射電訊號不明顯的中子星兩者在α-ζ平面上的分佈有所不同。

To investigate a possible reason of the difference between the radio-quiet neutron stars and radio pulsars, we determined the possible ranges of magnetic inclination angle α and the observer's viewing angleζfor several radio-quiet neutron stars with X-ray thermal emission. With a given surface temperature distribution of a neutron star and assuming the surface emission is described by Plank function, we modeled light curves and spectra. Asαandζare parameters in our model, the possible range of these two angles for radio-quiet neutron stars can be inferred by comparing the computed flux and pulsed fraction with the observed ones. Our calculation included photon path bending and gravitational redshift. Our result shows no significant sign of the different distribution in the α-ζplane for radio-quiet neutron stars and radio pulsars. Besides, we discussed spectra and light curve behaviors due to the effect of gravity, temperature distribution and beaming effects (limb-darkening and magnetic beaming).

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