Identification

Title

Electron impact ionization: A new parameterization for 100 eV to 1 MeV electrons

Abstract

We present a new parameterization of the altitude profile of the ionization rate in the Earth's atmosphere due to precipitating energetic electrons. Precipitating electrons are assumed to have a Maxwellian energy distribution and an isotropic pitch angle distribution above the atmosphere. In this study, two electron transport models (whose validity has been verified by observations) are employed to calculate the ionization rate, to which we have fit our new parameterization. To derive a new parameterization, we follow a similar scheme to that of Roble and Ridley (1987) but take into account further functional dependence on the incident electron energy. As a result, the new method presented in this paper provides a highly improved prediction for electron impact in a significantly extended energy range from 100 eV to 1 MeV, spanning 4 orders of magnitude. Note that we have neglected the contribution of bremsstrahlung X rays generated by energetic electrons, which are mostly important below 50 km altitude. The comparison of parameterization results with model calculations shows that the errors generally fall well within ±5% in both the altitude-integrated total ionization rate and the peak value. The altitude profile as a whole is also accurately predicted, with errors in the altitudes of the peak and e-folding ionization rates significantly less than 5 km. The proposed new parameterization method with high accuracy is thus ready to be implemented into global models to assess the electron impact on the ionosphere and the atmosphere.

Resource type

document

Resource locator

Unique resource identifier

code

https://n2t.org/ark:/85065/d7028rrt

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

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Temporal reference

Temporal extent

Begin position

End position

Dataset reference date

date type

publication

effective date

2008-09-11T00:00:00Z

Frequency of update

Quality and validity

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Conformity

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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