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The AMS02 collaboration has recently published high precision dailymeasurements of the spectra of cosmic ray protons, helium nuclei and electronstaken during a time interval of approximately 10 years from 2011 to 2020.Positron spectra averaged over distinct 27 days intervals have also been madepublic. The AMS02 collaboration has shown some intriguing "hysteresis" effectsobserved comparing the fluxes of protons and helium nuclei or protons andelectrons. In this work we address the question of the origin of these effects.We find that the spectral distortions generated by propagation in theheliosphere are significantly different for particles with electric charge ofopposite sign (an effect already well established), with different behaviourbefore and after the solar magnetic field polarity reversal at solar maximum.This results in hysteresis effects for the p/e comparison that follow the22-year solar cycle. On the other hand particles with electric charge of thesame sign suffer modulations that are approximately equal. The hysteresiseffects observed for a helium/proton comparison can then be understood as theconsequence of the fact that the two particles have interstellar spectra ofdifferent shape, and the approximately equal spectral distortions generated bypropagation in the heliosphere have a rigidity dependence that is a function oftime. These hysteresis effects can in fact be observed studying the timedependence of the shape of the spectra of a single particle type, and alsogenerate short time loop-like structures in the hysteresis curves correlatedwith large solar activity events such as CME's. A description of solarmodulations that includes these effects must go beyond the simple Force FieldApproximation (FFA) model. A minimal, two-parameter generalization of the FFAmodel that gives a good description of the observations is presented.

On the "Hysteresis Effects" observed by AMS02 in Cosmic Ray Solar Modulations