Heliospheric modulation strength during the neutron monitor era

Using a stochastic simulation of a one-dimensional heliosphere we calculate galactic cosmic ray spectra at the Earth's orbit for different values of the heliospheric modulation strength. Convoluting these spectra with the specific yield function of a neutron monitor, we obtain the expected neutron monitor count rates for different values of. Finally, inverting this relation, we calculate the modulation strength using the actually recorded neutron monitor count rates. We present the reconstructed annual heliospheric modulation strengths for the neutron monitor era (1953-2000) using several neutron monitors from different latitudes, covering a large range of geomagnetic rigidity cutoffs from polar to equatorial regions. The estimated modulation strengths are shown to be in good agreement with the corresponding estimates reported earlier for some years.