Journal article
Observations of the inner radiation belt: CRAND and trapped solar protons
Journal of geophysical research. Space physics, Vol.119(8), pp.6541-6552
08/2014
DOI: 10.1002/2014JA020188
Abstract
Measurements of inner radiation belt protons have been made by the Van Allen Probes Relativistic Electron‐Proton Telescopes as a function of kinetic energy (24 to 76 MeV), equatorial pitch angle, and magnetic L shell, during late 2013 and early 2014. A probabilistic data analysis method reduces background from contamination by higher‐energy protons. Resulting proton intensities are compared to predictions of a theoretical radiation belt model. Then trapped protons originating both from cosmic ray albedo neutron decay (CRAND) and from trapping of solar protons are evident in the measured distributions. An observed double‐peaked distribution in L is attributed, based on the model comparison, to a gap in the occurrence of solar proton events during the 2007 to 2011 solar minimum. Equatorial pitch angle distributions show that trapped solar protons are confined near the magnetic equator but that CRAND protons can reach low altitudes. Narrow pitch angle distributions near the outer edge of the inner belt are characteristic of proton trapping limits.
Key Points
Radiation belt protons have been measured by Van Allen Probes/REPTHigh‐energy proton contamination is removed by a probabilistic analysis methodPitch angle distributions reveal CRAND and solar origins of trapped protons
Details
- Title: Subtitle
- Observations of the inner radiation belt: CRAND and trapped solar protons
- Creators
- R. S Selesnick - Kirtland Air Force BaseD. N Baker - University of Colorado BoulderA. N Jaynes - University of Colorado BoulderX Li - University of Colorado BoulderS. G Kanekal - Goddard Space Flight CenterM. K Hudson - Dartmouth CollegeB. T Kress - Dartmouth College
- Resource Type
- Journal article
- Publication Details
- Journal of geophysical research. Space physics, Vol.119(8), pp.6541-6552
- DOI
- 10.1002/2014JA020188
- ISSN
- 2169-9380
- eISSN
- 2169-9402
- Number of pages
- 12
- Language
- English
- Date published
- 08/2014
- Academic Unit
- Physics and Astronomy; University College Courses
- Record Identifier
- 9984199784402771
Metrics
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