High-energy diffuse gamma-ray and neutrino emission are expected from the Galactic plane, generated by hadronuclear interactions between cosmic rays and the interstellar medium. Therefore, measurements of this diffuse emission will provide important clues to the origin and nature of Galactic cosmic rays. Comparing the latest observations of the Large High-Altitude Air Shower Observatory and IceCube on diffuse Galactic gamma-ray and neutrino emission, respectively, we suggest that the diffuse gamma-ray emission at multi-teraelectronvolt energies contains a considerable leptonic component. By modelling the gamma-ray halos powered by middle-aged pulsars in our Galaxy, taking into account the magnetic field configuration and the interstellar radiation field in the Galaxy, we demonstrate that the collective contribution of pulsar halos can account for the excess in the measured diffuse gamma-ray emission with respect to the predicted flux from cosmic-ray–interstellar medium interactions.

预计银河平面会发射高能弥散伽马射线和中微子，这是由宇宙射线和星际介质之间的强核相互作用产生的。因此，对这种漫射发射的测量将为银河宇宙射线的起源和性质提供重要线索。比较大型高空空气簇射天文台和冰立方分别对银河系弥漫伽马射线和中微子发射的最新观测结果，我们认为多太电子伏能量的弥散伽马射线发射包含相当多的轻子成分。通过对银河系中年脉冲星驱动的伽马射线晕进行建模，考虑到银河系中的磁场配置和星际辐射场，我们证明脉冲星晕的集体贡献可以解释测量中的过量扩散伽马射线发射与宇宙射线-星际介质相互作用的预测通量有关。