The tilt effect on cutoff
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Abstract
The effect that the tilt of the magnetic dipole with respect to the solar wind flow has on the cutoff energy cosmic ray protons is analysed for different local times of vertical arrival. For the study College Station, with an invariant latitude ͌ 64°, was selected. It was found that the computed cutoff energies for different tilt angles may differ by more than 20 MeV at the same time of arrival. The greatest differences were found at 18H of local time and the smallest at 6H. The. diurnal variation of the cutoff, taking into account the diurnal variation of the tilt, was also calculated during winter and summer solstices for a station with λinv=64° y una ϕ mag=Oº and compared with the diurnal variation for zero tilt. Differences higher than 10 MeV were found.
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References
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