The modification of the rotating vector model in the case of magnetars are calculated. Magnetars may have twisted magnetic field compared with normal pulsars. The polarization position angle of magnetars will change in the case of a twisted magnetic field. For a twisted dipole field, we found that the position angle will change both vertically and horizontally. During the untwisting process of the magnetar magnetosphere, the modifications of the position angle will evolve with time monotonously. This may explain the evolution of the position angle in magnetar PSR J1622-4950 and XTE J1810-197. The relation between the emission point and the line of sight will also change. We suggest every magnetospheric models of magnetars also calculate the corresponding changes of position angle in their models. Order of magnitude estimation formula for doing this is given. This opens the possibility to extract the magnetic field geometry of magnetars from their radio polarization observations.

中文翻译：

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磁星的旋转矢量模型

计算了磁星情况下旋转矢量模型的修正。与普通脉冲星相比，磁星可能具有扭曲的磁场。在扭转磁场的情况下，磁星的极化位置角会发生变化。对于扭曲偶极子场，我们发现位置角会在垂直和水平方向发生变化。在磁星磁层解旋过程中，位置角的变化会随时间单调演化。这可以解释磁星 PSR J1622-4950 和 XTE J1810-197 中位置角的演变。发射点与视线的关系也会发生变化。我们建议每个磁星的磁层模型也计算其模型中相应的位置角变化。给出了执行此操作的数量级估计公式。这开启了从其无线电极化观测中提取磁星磁场几何形状的可能性。