# Presentation: 935759

## RPI/IMAGE Signatures of Non-Maxwellian Electron-Velocity Distributions and of Solar-Wind/Magnetosphere Interactions

- Vinas, A.F., R.L. Mace, and R.F. Benson, Dispersion characteristics for plasma resonances of Maxwellian and Kappa distribution plasmas and their comparisons to the IMAGE/RPI observations, *J. Geophys. Res.*, *110*, A06202, doi:10.1029/2004JA010967, 2005
- RPI/IMAGE plasma and magnetic signatures of solar-wind/magnetosphere interactions, R F. Benson, V A. Osherovich, J. Fainberg, J. L. Green, S. Boardsen, L. N. Garcia,  N. Tsyganenko, B. W. Reinisch, Spring 2006 AGU Meeting (SM42A-05, Thurs. 25 May 2006 11:45)

## Numerical solutions

- of warm-plasma
- dispersion curves
- for:
- Kappa (dashed)
- Maxwellian (solid)

- Vinas et al., JGR,110, A06202, 2005

## Qn comparison:

- Vinas et al., JGR,110, A06202, 2005

- Kappa (dashed)
-   (Kappa = 2.1)
- Maxwellian (solid)
- Observed (O)

## RPI/IMAGE plasma and magnetic signatures of solar-wind/magnetosphere interactions

- Robert F. Benson
- Vladimir A. Osherovich(L3-Com)
- Joseph Fainberg
- James L. Green
- Scott Boardsen(UMBC-GEST)
- Leonard N. Garcia(QSS)
- Nikolai Tsyganenko(USRA)
- Goddard Space Flight Center, Greenbelt, Maryland
- Bodo W. Reinisch
- University of Massachusetts Lowell, Lowell, Massachusetts

## OUTLINE

- Radio Plasma Imager (RPI)/IMAGE data near apogee
- Compare quiet and disturbed days (30 & 31 March 2001)
- Determine electron plasma-to-cyclotron frequency ratio
- electron plasma frequency fpe  √Ne
- electron cyclotron frequency fce  |**B**|
- fpe/fce  (Debye)/r(cyclotron)
- fpe/fce  c/v(Alfven)
- Compare above RPI-determined values to model values
- Calculate the solar-wind index QI
- QI = (B2/8)/(v2/2) = (1/MA)2
- Compare magnetospheric fpe/fce and solar-wind QI fluctuations

## IMAGE apogee

- regions (shaded)
- for
- fpe/fce comparisons
- between
- quiet (30 March)
- and
- disturbed (31 March)
- conditions

- Great magnetic
- storm of
- 31 March 2001

## Quiet-day RPI/IMAGE passive dynamic spectrum

## Quiet-day RPI/IMAGE passive dynamic spectrumwith superimposed RPI-determined (active sounding)fpe and fce values

**fce Resonance**

## Disturbed-day RPI/IMAGE passive dynamic spectrum

## Disturbed-day RPI/IMAGE passive dynamic spectrumwith superimposed RPI-determined (active sounding)fpe and fce values

**fpe Resonance**

## RPI/IMAGE near-apogee

- high-resolution (300 Hz)
- plasmagrams

- 30 March 2001
- 0203 UT
- nfce resonances only

- 31 March 2001
- 1611 UT
- fuh, fpe, fDn, fQn
- and
- nfce resonances
- fuh2 = fpe2 + fce2

- 6       Frequency (kHz)     48

## 31 March 2001

- RPI/IMAGE
- plasmagrams
- normalized (by fce)
- and ordered by
- fpe/fce
- (from 2.17 to 2.28)

- 2105 UT
- 1611 UT
- 2053 UT

## Deviation of model fce (TS05) from RPI (res) %TS05 from Tsyganenko & Sitnov, JGR, 2005

- Deviation of model fce (TS05) from RPI (res) %TS05 from Tsyganenko & Sitnov, JGR, 2005

## Ratio of RPI fpe to model fpemodel fpe ~ composite of various magnetospheric models

## fpe/fce RPI(resonance) compared to model(RPI composite fpe model)/(TS05 fce)

## QI = (B2/8)/(v2/2)

- Great 31 March 2001 storm
- caused by 2nd of 3 magnetic
- clouds in 30-day interval

- Solar-wind QI
- QI = (B2/8)/(v2/2)
- typically ≈ 0.01
- Osherovich et al., GRL, 26, 1999

- In magnetic clouds
- QI increases by
- one to two
- orders of magnitude
- Osherovich et al., Solar Wind 10, 2003

## 31 March 2001 solar-wind QI & magnetospheric fpe/fce

- 20-min averages
- highly correlated
- cc = 87%

## Summary

- 30/31 March 2001 storm-induced 8 RE polar-cap changes
- fpe increased by ~ factor of 2 to 4
- fce typically increases by < factor of 2
- fpe(res)/fce(res)(disturbed) ~ 2 to 5 (rich res spectrum)
- RPI plasma-resonance and model values compared
- fce(TS05) within 15% of fce(res) on quiet and disturbed
-  fpe(res) ~ > 2fpe(mod)(quiet)  Ne(res) > 4Ne(mod)
-                  > 4 to 8fpe(mod) (disturbed)
-                         Ne(res) > 16 to 64Ne(mod)
- Solar-wind QI enhancements as magnetic-cloud-induced magnetic-storm indicators
- Disturbed s-w QI & magnetspheric fpe/fce highly correlated
- cc of fluctuations = 87 % with 3-hr time delay of fpe/fce