Showers initiated by high-energy cosmic rays can inject secondary
particles into interplanetary space. This will happen best if the
primary particle arrives at an impact parameter such that the column
mass corresponds to a nuclear interaction length. A tangential
shower develops at this point in the atmosphere, and it will then
project early secondary particles of all sorts in the...
From a survey of solar energetic particle events observed by both the STEREO spacecraft and at the Earth in 2009-2012 during solar cycle 24, Richardson et al. (Solar Physics, 289,3059, 2014) obtained a formula relating the SEP peak intensity at 14-24 MeV with the speed of the associated coronal mass ejection and its direction with respect to the observing spacecraft. This suggests that the...
One of the remaining questions of solar energetic particle (SEP) events is their links to solar regions and eruptions from them. The solar origin is more strongly found in SEPs at high energies including electrons, and during the early phase. We experience SEP events that apparently contradict our expectation on the onset time, the flux of, and rise time to, the (first) peak, and the angular...
