过渡脉冲星中的伽马射线模式
Gamma-ray Modes in a Transitional Pulsar
中文总结 AI 辅助
研究首个确认的过渡毫秒脉冲星PSR J1023+0038中的伽马射线模式，通过堆叠Fermi-LAT数据发现伽马射线与X射线反相关，与现有模型矛盾，鉴于伽马射线高模式射电更亮且可能无脉冲星风，推测GeV伽马射线中喷流发射占主导。
中文摘要 AI 辅助
过渡毫秒脉冲星（tMSPs）呈现出独特的亚发光盘状态，处于吸积和旋转功率的交叉点，在两种不同的X射线模式之间切换。我们展示了在首个确认的tMSP——PSR J1023+0038中伽马射线模式的发现，通过在模式期间堆叠费米大面积望远镜（Fermi-LAT）数据（利用同步X射线观测识别模式）。令人惊讶的是，我们发现在这种模式切换期间伽马射线和X射线呈反相关：在X射线低模式下伽马射线通量更高，反之亦然。这与现有模型矛盾，该模型预测通过同步辐射和逆康普顿过程，脉冲星风与周围盘相互作用会产生明亮的伽马射线。由于在伽马射线高（X射线低）模式下可能不存在脉冲星风，且该模式在射电波段也更亮，我们认为GeV伽马射线中喷流发射占主导。
英文摘要
Transitional millisecond pulsars (tMSPs) exhibit a unique sub-luminous disk state, at the cross-roads between accretion and rotation power, where they switch between two distinct X-ray modes. We present the discovery of gamma-ray modes in PSR J1023+0038, the first confirmed tMSP, from stacking Fermi-LAT data during the modes (which we identify using simultaneous X-ray observations). Surprisingly, we find that gamma-rays and X-rays are anti-correlated during this mode switching: the gamma-ray flux is higher in the X-ray low mode, and vice versa. This contradicts the state-of-the-art model, which predicts bright gamma-rays from the interaction between the pulsar wind and surrounding disk via synchrotron and inverse Compton processes. Because the pulsar wind is likely absent in the gamma-ray high (X-ray low) mode, which is also brighter in the radio band, we suggest that jet emission is dominant in GeV gamma-rays.
