Identification

Title

Effects of solar wind ultralow-frequency fluctuations on plasma sheet electron temperature: Regression analysis with support vector machine

Abstract

To investigate whether ultralow-frequency (ULF) fluctuations from 0.5 to 8.3 mHz in the solar wind and interplanetary magnetic field (IMF) can affect the plasma sheet electron temperature (T-e) near geosynchronous distances, we use a support vector regression machine technique to decouple the effects from different solar wind parameters and their ULF fluctuation power. T-e in this region varies from similar to 0.1 to 10 keV with a median of 1.3 keV. We find that when the solar wind ULF power is weak, T-e increases with increasing southward IMF B-z and solar wind speed, while it varies weakly with solar wind density. As the ULF power becomes stronger during weak IMF B-z (similar to 0) or northward IMF, T-e becomes significantly enhanced, by a factor of up to 10. We also find that mesoscale disturbances in a time scale of a few to tens of minutes as indicated by AE during substorm expansion and recovery phases are more enhanced when the ULF power is stronger. The effect of ULF powers may be explained by stronger inward radial diffusion resulting from stronger mesoscale disturbances under higher ULF powers, which can bring high-energy plasma sheet electrons further toward geosynchronous distance. This effect of ULF powers is particularly important during weak southward IMF or northward IMF when convection electric drift is weak.

Resource type

document

Resource locator

Unique resource identifier

code

http://n2t.net/ark:/85065/d7930w4h

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

Classification of spatial data and services

Topic category

geoscientificInformation

Keywords

Keyword set

keyword value

Text

originating controlled vocabulary

title

Resource Type

reference date

date type

publication

effective date

2016-01-01T00:00:00Z

Geographic location

West bounding longitude

East bounding longitude

North bounding latitude

South bounding latitude

Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2017-04-01T00:00:00Z

Frequency of update

Quality and validity

Lineage

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Limitations on public access

None

Responsible organisations

Responsible party

contact position

OpenSky Support

organisation name

UCAR/NCAR - Library

full postal address

PO Box 3000

Boulder

80307-3000

email address

opensky@ucar.edu

web address

http://opensky.ucar.edu/

name: homepage

responsible party role

pointOfContact

Metadata on metadata

Metadata point of contact