标题： 双星脉冲星PSR J0737-3039中的掩食和轨道调制现象 显示英文标题

标题： Eclipses and orbital modulations in binary pulsar PSR J0737-3039

摘要： 双星射电脉冲星系统 J0737-3039 因其非常紧密的轨道、有利的脉冲星旋转轴和磁轴方向以及极为偶然的轨道取向，提供了研究脉冲星磁层内部结构的绝佳机会。 在这个系统中，毫秒脉冲星 A 每次绕行都会被遮挡一次。 在遮挡期间，可以清楚地观察到以脉冲星 B 的 2.77 秒周期为调制的现象，明确指向了遮挡的磁层起源。 基于同步辐射吸收在脉冲星 B 的闭合磁力线上的简单几何模型，可以成功重现遮挡光变曲线直至细微之处。 这种详细的吻合证实了中子星磁场的偶极结构。 由于脉冲星 B 的测地进动，该模型对遮挡轮廓的时间演化给出了明确预测。 此外，脉冲星 B 的强度表现出轨道调制，在两个短轨道相位处尤为明亮。 我们表明，这些调制是由脉冲星 A 风扭曲脉冲星 B 磁层引起的，这导致了轨道相位相关的无线电波发射方向变化。 因此，脉冲星 B 在所有时间都本质上很亮，但在大多数轨道相位中其辐射束错过了地球。 显示英文摘要

摘要： Binary radio pulsar system J0737-3039 provides an exceptional opportunity to study innermost structure of pulsar magnetospheres due to very tight orbit, favorable directions of pulsars' rotation and magnetic axes and extremely fortuitous orientation of the orbit. In this system the millisecond pulsar A is eclipsed once per orbit. During eclipse a clear modulation at the 2.77 s period of pulsar B is seen, pointing unambiguously to magnetospheric origin of eclipses. A simple geometric model, based on the idea that the radio pulses are attenuated by synchrotron absorption on the closed magnetic field lines of pulsar B, can successfully reproduces the eclipse light curves down to intricate details. This detailed agreement confirms the dipolar structure of the neutron star's magnetic field. The model gives clear predictions for temporal evolution of eclipse profile due to geodetic precession of pulsar B. In addition, pulsar B shows orbital modulations of intensity, being especially bright at two short orbital phases. We showed that these modulations are due to distortion of pulsar B magnetosphere by pulsar A wind which produces orbital phase-dependent changes of the direction along which radio waves are emitted. Thus, pulsar B is intrinsically bright at all times but its radiation beam misses the Earth at most orbital phases.