K/sub p/ index correlations with solar-wind parameters during the first and second stages of a recurrent geomagnetic storm

Journal Article · Sat Dec 01 04:00:00 EST 1973 · Planet. Space Sci., v. 21, no. 12, pp. 2139-2147

OSTI ID:4364997

Bobrov, M S

>The dependence of geomagnetic activity during a recurrent magnetic storm on the solar-wind magnetic field and plasma parameters has been studied. According to variations of solarwind magnetic field strength B, a recurrent magnetic storm is divided into two stages: the first proceeding during the peak of B, and the second proceeding after the return of B to quiet level. The K/sub p/ index vs solar-wind parameters scattering diagrams for stages I and II differ significantly. In particular, the random scattering for stage I is much larger than for stage II. It was found that for stage I the K/sub p/ index correlates with B, with the sign and value of north-south field component B/sub z/ and with the magnitude DELTA B of field fluctuations, the situation being similar to that during sporadic magnetic storms, though the scale of the event is smaller. For stage II, the K/sub p/ index does not correlate with B, but strongly correlates with DELTA B and weaker-with B/sub z/. So geomagnetic activity at stage II is supported mainly by solar-wind magnetic field fluctuations. The dependence of the a index on plasma parameters (concentration of protons n, bulk velocity v and temperature T) is weak for both stages. (auth)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-29-013717
• OSTI ID: 4364997
• Journal Information: Planet. Space Sci., v. 21, no. 12, pp. 2139-2147, Journal Name: Planet. Space Sci., v. 21, no. 12, pp. 2139-2147; ISSN PLSSA
• Country of Publication: United Kingdom
• Language: English

Related Subjects

*MAGNETIC STORMS-- PLASMA
*SOLAR WIND-- MAGNETIC FIELDS
GEOMAGNETIC FIELD
N58300* --Physics (Atmospheric)--Magnetospheric Phenomena
PROTONS
TEMPERATURE DEPENDENCE