Role of heavier-than-proton nuclei in neutron monitor response

Abstract

Heavier-than-proton nuclei in cosmic rays are responsible for up to 45% of neutron monitor (NM) response depending on the level of solar modulation as well as the geomagnetic rigidity cutoff and altitude of a given NM location. Therefore, a careful consideration of these heavy species is important for an accurate analysis of NM data, including a reconstruction of the solar modulation potential using the worldwide NM network data. Recently, the AMS-02 experiment allowed us to directly verify the NM response to heavy particles. In this work, we evaluate the expected contribution of heavy nuclei into the NM response considering different models of the local interstellar spectrum and also for different levels of solar activity.