Cosmic Ray Modulation Studies Using Neutron Monitor and Spacecraft Detectors Near the Earth

University Of New Hampshire, Durham NH

Investigators

Abstract

Abstract: ATM 00-02744 Proposal Title: Cosmic Ray Modulation Studies Using Neutron Monitor and Spacecraft Detectors Near the Earth Principal Investigator: John A. Lockwood, University of New Hampshire The investigators will study cosmic ray solar modulation near the Earth during the coming solar maximum and consequent reversal of the solar magnetic field. The main effort is to continue operation of the Mount Washington neutron monitor, and to employ the data obtained, together with data from other neutron monitors and spacecraft to compare the onset of the current modulation cycle with previous cosmic ray modulation cycles. Galactic cosmic ray fluxes vary, or are "modulated" in response to changes in the interplanetary magnetic environment, which in turn derives from the magnetic activity on the surface of the Sun. This magnetic activity is most manifest in the cycle of sunspots and solar flares lasting approximately eleven years. However the polarity of the magnetic field reverses every sunspot cycle, so the true magnetic cycle spans 22 years. Only two magnetic cycles have been observed with high accuracy particle detectors like the neutron monitor on Mount Washington, which has operated continuously from 1954 to the present. The investigators will also study solar cosmic ray events in collaboration with colleagues at the University of Bern, Switzerland.