Accession Number:

ADA202510

Title:

Time-Weighted Accumulations ap(Tau) and Kp(Tau)

Descriptive Note:

Technical rept.

Corporate Author:

ROYAL AEROSPACE ESTABLISHMENT FARNBOROUGH (UNITED KINGDOM)

Personal Author(s):

Report Date:

1988-07-01

Pagination or Media Count:

9.0

Abstract:

The planetary geomagnetic indices Kp and ap are widely used in space geophysics. These provide an estimate of maximum magnetic perturbation within a 3-hour period. Many geophysical properties are clearly related to the indices, through energy transfer from a common disturbance source,but direct correlation is often lacking because of poor matching between the frequency of sampling and the physical response functions. The index aptau is a simple accumulation of the linear ap calculated with an attenuation factor tau included to take account of natural temporal relaxation. The case for aptau and the related Kptau is made using applications to the variability of the plasma environment in the ionosphere and inner magnetosphere. These examples of improved correlation suggest that time-weighted integration might profitably be applied to other indices. Keywords Great Britain Fregron.

Subject Categories:

  • Geomagnetism

Distribution Statement:

APPROVED FOR PUBLIC RELEASE