HR: 0830h
AN: SH21B-0144    [PDF]
TI: Interplanetary Disturbances With High Values of the Solar Wind Quasi-Invariant
AU: Fainberg, J
EM: joseph.fainberg@nasa.gov
AF: NASA Goddard Space Flight Center, Code 692, Greenbelt, MD 20771 United States
AU: * Osherovich, V A
EM: vladimir@urap.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Code 690.2, Greenbelt, MD 20771 United States
AB: The solar wind quasi-invariant ($QI$) has been introduced as the energy density ratio $QI=(B^2/8\pi)/(\rho v^2/2)$ [Osherovich, Fainberg and Stone, GRL, 26, 16, 2597, 1999]. $B$ is the interplanetary magnetic field strength, $v$ is the bulk velocity and $\rho$ is the plasma density. The significance of this result has been supported by the studies of $QI$ from 0.7 AU to 28 AU, using data from Pioneer-Venus Orbiter and the Voyagers [Fainberg, Osherovich and Stone, GRL, 28, 8, 1447, 2001; Fainberg and Osherovich, Proc. 10th European Sol. Phys. Mtg, ESA SP-506, vol. 1, 43, 2002]. Magnetic clouds have anomalously large values of $QI$ of 10-100 times higher than $QI_{median}$ because of their larger than average $B$ and lower $\rho$ due to the expansion. We report the contribution of high $QI$ events (not only magnetic clouds) to the yearly $QI$ based on hourly values of $QI$. The geomagnetic effectiveness of individual high $QI$ events and their impact on geomagnetic indices will be discussed.
DE: 1650 Solar variability
DE: 2111 Ejecta, driver gases, and magnetic clouds
DE: 2162 Solar cycle variations (7536)
SC: SPA - Solar and Heliospheric Physics [SH]
MN: 2003 Fall Meeting