New Chorus Diffusion Coefficients for Radiation Belt Modelling

Whistler mode chorus is an important magnetospheric wave emission playing a major role in radiation belt dynamics, where it contributes to both the acceleration and loss of relativistic electrons. In this study we compute bounce and drift averaged chorus diffusion coefficients for 3.0 < L* < 6.0, using the TS04 external magnetic field model, taking into account co-located near-equatorial measurements of the wave intensity and fpe/fce, by combining the Van Allen probes measurements with data from a multi-satellite VLF wave database. The variation of chorus wave normal angle with spatial location and fpe/fce is also taken into account. We find that chorus propagating at small wave normal angles has the dominant contribution to the diffusion rates in most MLT sectors. However, in the region 4 <= MLT < 11 high wave normal angles dominate at intermediate pitch angles. In the region 3 < L* < 4, the bounce and drift averaged pitch angle and energy diffusion rates during active conditions are primarily larger than those in our earlier models by up to a factor of 10 depending on energy and pitch angle. Further out, the results are similar. We find that the bounce and drift averaged energy and pitch angle diffusion rates can be significantly larger than the new model in regions of low fpe/fce,eq, where the differences can be up to a factor of 10 depending on energy and pitch angle.

Funding was provided by the Natural Environment Research Council (NERC) Highlight Topic grant NE/P01738X/1 (Rad-Sat) and the NERC grants NE/V00249X/1 (Sat-Risk), NE/R016038/1 and NE/X000389/1.

Alternate title: Polar Data Centre (PDC) record GB/NERC/BAS/PDC/01782

Date (Publication): 2023-10-19

Citation identifier: http://www.antarctica.ac.uk/dms/metadata.php?id= / GB/NERC/BAS/PDC/01782

Point of contact

Organisation name	Individual name	Electronic mail address	Role
British Antarctic Survey		pdc@bas.ac.uk	Custodian
NERC EDS UK Polar Data Centre	Wong, J.	pdc@bas.ac.uk	Originator

Maintenance and update frequency: Unknown

Keywords

NDGO0001

NERC OAI Harvesting

NERC_DDC

GCMD Parameter Valids

EARTH SCIENCE > Sun-earth Interactions > Ionosphere/Magnetosphere Dynamics

BAS Free-text keywords

Chorus Waves
Electron Diffusion
Radiation Belts

Use limitation: Data supplied under Open Government Licence v3.0 http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/.

Access constraints: Other restrictions

Other constraints: Data supplied under Open Government Licence v3.0 http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/.

Language: English

Topic category

Climatology, meteorology, atmosphere

Begin date: 2012-11-07

End date: 2019-10-14

Reference system identifier: OGP / urn:ogc:def:crs:EPSG::4326

Distribution format

Distributor contact

Organisation name	Individual name	Electronic mail address	Role
Polar Data Centre - British Antarctic Survey		pdc@bas.ac.uk	Distributor

OnLine resource

Protocol	Linkage	Name
http		GET DATA

Hierarchy level: Dataset

Domain consistency

Measure identification: INSPIRE / Conformity_001

Conformance result

Title: INSPIRE Data Specification on unknown theme Guidelines

Date

Explanation: See the referenced specification

Pass: No

Statement: The wave data have been calibrated and quality-controlled prior to release. We also omitted data during thruster firing, eclipse and charging times.