Premium
A Solar Cycle of Cosmic Ray Fluxes for 2006–2014: Comparison between PAMELA and Neutron Monitors
Author(s) -
Koldobskiy Sergey A.,
Kovaltsov Gennady A.,
Usoskin Ilya G.
Publication year - 2018
Publication title -
journal of geophysical research: space physics
Language(s) - English
Resource type - Journals
eISSN - 2169-9402
pISSN - 2169-9380
DOI - 10.1029/2018ja025516
Subject(s) - cosmic ray , physics , neutron , neutron monitor , nuclear physics , payload (computing) , spectral line , modulation (music) , astrophysics , computational physics , astronomy , computer network , network packet , computer science , acoustics
A comparison of cosmic proton spectra directly measured by the Payload for Antimatter Matter Exploration and Light‐nuclei Astrophysics (PAMELA) experiment during 2006–2014 with data of polar neutron monitors for the same time interval is presented. It is shown that the measured spectra are well described by the force‐field model for the modulation potential range 350–750 MV. The obtained modulation potential agrees with that calculated from the data of the world neutron monitor network for low solar activity between 2006 and 2012 but diverges during the maximum of solar cycle. The empirical relation between the modulation potential and the (inverted) neutron monitor count rate appears somewhat steeper than the modeled one, as confirmed also by data from fragmentary balloon‐borne measurements. A reason for the discrepancy is unclear and calls for additional study using independent data sets.