Anisotropy in the South Atlantic Anomaly
From June 2000 through July 2006, the TSX-5 satellite measured proton fluxes in the Earth?s magnetosphere using its CEASE instrument. A review of the satellite data by scientists at AFRL/VSBX revealed an unanticipated, recurring bi-modal structure in histograms of the proton counts. This research id...
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ftdtic:ADA464816 2023-05-15T18:21:10+02:00 Anisotropy in the South Atlantic Anomaly Easley, Shaun M. AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT/DEPT OF ENGINEERING PHYSICS 2007-01 text/html http://www.dtic.mil/docs/citations/ADA464816 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA464816 en eng http://www.dtic.mil/docs/citations/ADA464816 Approved for public release; distribution is unlimited. DTIC Operations Research Crystallography *ANOMALIES *ANISOTROPY *TELEMETERING DATA *SOUTH ATLANTIC OCEAN DATA BASES MATHEMATICAL MODELS PITCH(INCLINATION) COUNTING METHODS SOLAR CYCLE MAGNETOSPHERE SCIENTISTS LOW ALTITUDE HIGH ALTITUDE SAMPLING PROTONS DETECTORS MEASUREMENT ANGLES SPACE WEATHER SOUTH ATLANTIC ANOMALY EAST-WEST EFFECT ANISOTROPY PITCH ANGLE DISTRIBUTION TRI-SERVICE EXPERIMENT-5 (TSX-5) COMPACT ENVIRONMENTAL ANOMALY SENSOR (CEASE) IGRF MSIS Text 2007 ftdtic 2016-02-22T08:50:00Z From June 2000 through July 2006, the TSX-5 satellite measured proton fluxes in the Earth?s magnetosphere using its CEASE instrument. A review of the satellite data by scientists at AFRL/VSBX revealed an unanticipated, recurring bi-modal structure in histograms of the proton counts. This research identified the bi-modal behavior as anisotropic in nature, and the result of two separate processes. At low altitudes the anisotropy was well described by the classic ?East-West Effect.? Comparisons of the satellite data to simple analytical models are presented. At high altitudes, the anisotropy was the result of the detector measuring protons at different pitch angles when looking east vs. west. The sampled pitch angles were also found to be function of location, leading to a latitudinal variation to this anisotropy. Finally, we also examined a series of unusually high readings that affected some of the statistics in this study. These anomalous counts were found to have a possible solar cycle dependence leading to questions about the suitability of the current timeindependent scheme used to sort the satellite?s data set. Other possible explanations for the anomalous counts are also presented. The original document contains color images. Text South Atlantic Ocean Defense Technical Information Center: DTIC Technical Reports database |
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Open Polar |
collection |
Defense Technical Information Center: DTIC Technical Reports database |
op_collection_id |
ftdtic |
language |
English |
topic |
Operations Research Crystallography *ANOMALIES *ANISOTROPY *TELEMETERING DATA *SOUTH ATLANTIC OCEAN DATA BASES MATHEMATICAL MODELS PITCH(INCLINATION) COUNTING METHODS SOLAR CYCLE MAGNETOSPHERE SCIENTISTS LOW ALTITUDE HIGH ALTITUDE SAMPLING PROTONS DETECTORS MEASUREMENT ANGLES SPACE WEATHER SOUTH ATLANTIC ANOMALY EAST-WEST EFFECT ANISOTROPY PITCH ANGLE DISTRIBUTION TRI-SERVICE EXPERIMENT-5 (TSX-5) COMPACT ENVIRONMENTAL ANOMALY SENSOR (CEASE) IGRF MSIS |
spellingShingle |
Operations Research Crystallography *ANOMALIES *ANISOTROPY *TELEMETERING DATA *SOUTH ATLANTIC OCEAN DATA BASES MATHEMATICAL MODELS PITCH(INCLINATION) COUNTING METHODS SOLAR CYCLE MAGNETOSPHERE SCIENTISTS LOW ALTITUDE HIGH ALTITUDE SAMPLING PROTONS DETECTORS MEASUREMENT ANGLES SPACE WEATHER SOUTH ATLANTIC ANOMALY EAST-WEST EFFECT ANISOTROPY PITCH ANGLE DISTRIBUTION TRI-SERVICE EXPERIMENT-5 (TSX-5) COMPACT ENVIRONMENTAL ANOMALY SENSOR (CEASE) IGRF MSIS Easley, Shaun M. Anisotropy in the South Atlantic Anomaly |
topic_facet |
Operations Research Crystallography *ANOMALIES *ANISOTROPY *TELEMETERING DATA *SOUTH ATLANTIC OCEAN DATA BASES MATHEMATICAL MODELS PITCH(INCLINATION) COUNTING METHODS SOLAR CYCLE MAGNETOSPHERE SCIENTISTS LOW ALTITUDE HIGH ALTITUDE SAMPLING PROTONS DETECTORS MEASUREMENT ANGLES SPACE WEATHER SOUTH ATLANTIC ANOMALY EAST-WEST EFFECT ANISOTROPY PITCH ANGLE DISTRIBUTION TRI-SERVICE EXPERIMENT-5 (TSX-5) COMPACT ENVIRONMENTAL ANOMALY SENSOR (CEASE) IGRF MSIS |
description |
From June 2000 through July 2006, the TSX-5 satellite measured proton fluxes in the Earth?s magnetosphere using its CEASE instrument. A review of the satellite data by scientists at AFRL/VSBX revealed an unanticipated, recurring bi-modal structure in histograms of the proton counts. This research identified the bi-modal behavior as anisotropic in nature, and the result of two separate processes. At low altitudes the anisotropy was well described by the classic ?East-West Effect.? Comparisons of the satellite data to simple analytical models are presented. At high altitudes, the anisotropy was the result of the detector measuring protons at different pitch angles when looking east vs. west. The sampled pitch angles were also found to be function of location, leading to a latitudinal variation to this anisotropy. Finally, we also examined a series of unusually high readings that affected some of the statistics in this study. These anomalous counts were found to have a possible solar cycle dependence leading to questions about the suitability of the current timeindependent scheme used to sort the satellite?s data set. Other possible explanations for the anomalous counts are also presented. The original document contains color images. |
author2 |
AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING AND MANAGEMENT/DEPT OF ENGINEERING PHYSICS |
format |
Text |
author |
Easley, Shaun M. |
author_facet |
Easley, Shaun M. |
author_sort |
Easley, Shaun M. |
title |
Anisotropy in the South Atlantic Anomaly |
title_short |
Anisotropy in the South Atlantic Anomaly |
title_full |
Anisotropy in the South Atlantic Anomaly |
title_fullStr |
Anisotropy in the South Atlantic Anomaly |
title_full_unstemmed |
Anisotropy in the South Atlantic Anomaly |
title_sort |
anisotropy in the south atlantic anomaly |
publishDate |
2007 |
url |
http://www.dtic.mil/docs/citations/ADA464816 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA464816 |
genre |
South Atlantic Ocean |
genre_facet |
South Atlantic Ocean |
op_source |
DTIC |
op_relation |
http://www.dtic.mil/docs/citations/ADA464816 |
op_rights |
Approved for public release; distribution is unlimited. |
_version_ |
1766200310175367168 |