我們使用PSR B0656+14 和 PSR B1055-52,這兩顆有觀測到為兩個在X射線熱輻射分佈的波霎.其中較熱的部份被認為是來自波霎表面被加熱的極冠;而另一部份則為其他表面溫度所造成的.在考慮光被重力的彎曲的現在,我們計算可以觀測到的極冠和表面的比值.根據觀測和計算出來的比質,試圖研究極冠大小和在波霎上的幾何分佈與重力的關係.
結果顯示在PSR B0656+14這顆波霎需要到四倍一般規範的極冠角度才能達到觀測比值.如果不把極冠角度再放大,那麼磁傾角和觀測方向和波霎上的轉軸所夾的角度要相當接近,且波霎大約要有兩倍的太陽質量.然而,對於PSR B1055-52這顆波霎則只有規範極冠角度的三分之一不到.有可能的機制是粒子加速只打回波霎的邊緣而已.如此一來我們所觀測的比值就算合理了!

We computed the ratio of the heated-polar-cap area to the entire stellar surface taking into account the effect of gravity for PSR B0656+14 and PSR B1055-52, whose spectra can be fit with two blackbody components. Adopting the interpretation that the soft thermal component is from the entire surface and the hard one is from a heated polar cap, we study the dependence of the ratio on the assumed polar-cap size, geometry and surface gravity. Compared with observations, we may obtain some model constraints.
Our results show that the heated-polar-cap size of PSR B0656+14

should be at least four times its canonical value.For not involing too large a polar cap, the pulsar's magnetic axis and the line of sight should be close to the rotation axis,and the mass of the pulsar may be more than two times of solar mass.

However, in the case of PSR B1055-52,the heated-polar-cap size must be less than one-third of its canonical polar-cap size.

It is possible that the reheating only occurs at the edge of the polar cap.

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