University of Kansas X-Ray Emission in the Solar System

(DRAFT) Temporal and Spatial Variations of Heliospheric X-Ray Emissions Associated with Charge Transfer of the Solar Wind with Interstellar Neutrals I. P. Robertson, T. E. Cravens, and S. Snowden

Image: Jovian soft X-rays from ROSAT; courtesy of J. H. Waite.

ROSAT Long-Term Enhancement Data

Cravens et al. (2001) directly compared ROSAT LTE 1/4 keV data with measured solar wind proton fluxes for the same time period. Even though no selection was made with respect to look-direction, a significant correlation was found with a linear regression coefficient of R = 0.7. Cravens next plotted the total helium and geocoronal intensities versus ROSAT LTE data and found a strong correspondence between the modeled X-ray intensity and the LTE data. The downwind plot with Fahr's densities shows considerable more variation than the X-ray intensities Cravens used and, consequently, would show an even stronger correspondence between X-ray intensity and LTE data.

Conclusions

Our improved model of soft X-ray intensities observed at Earth further supports the suggestion that LTEs, in the observed soft X-ray background, can be explained by charge exchange between heavy solar wind ions and interstellar neutrals. Further improvements in the modeling of X-ray intensities should include:

1. A more accurate calculation of alpha for different species;
2. A solar wind model which includes latitudinal variations;
3. An improved model of the geocoronal x-ray emission.

References

• Return to abstract and index page for this draft manuscript.
• Return to Space Physics X-Ray Emission Main Page.
• Return to Space Physics Home Page.

Last modified Oct. 3, 2005 Tizby Hunt-Ward tizby@ku.edu