The sun itself does not appear to have a significant effect on muon
production. We therefore conclude muons are created primarily by extra-solar
cosmic rays. If the sun creates any cosmic rays, these rays are not energetic
enough to create muons when they hit the ionosphere.
We can determine the maximum energies of any cosmic ray protons emitted by the
sun by considering the muon production reaction. Muons are created when a
¹- decays into a neutrino and a muon. Because pions are only created when
a neutron and a proton combine according to the following equation,
p+n>¹ + ¹+ + ¹o + n + p |
(Equation 8) |
we know that the kinetic energy of the proton must be equal to the mass energies of the sum of the pions by conservation of energy. Therefore, the total energy of the proton is equal to its kinetic energy (or the sum of the pion masses) plus the mass of the proton, given by:
139.4MeV + 139.4 MeV + 135.0 MeV + 938.3 MeV = 1352 MeV |
(Equation 9) |
This
is the upper bound for the energy of protons produced by the sun. If the
energy of the proton was greater, we would see muons created by solar proton
radiation. We may then draw the conclusion that protons radiated by the solar
wind have an energy that is at most 1352 MeV.
We also conclude that increases in sunspots do not consistently correlate with
disturbances in the geomagnetic field. Effects on the geomagnetic field could
be caused by an increase in UV radiation from the sun and/or an increase in
charged particle radiation. If this charged particle radiation is proton
radiation, we may subsequently conclude that these protons have the same upper
energy bound as found in Equation 9 due to our solar-muon correlation.