University of Kansas X-Ray Pages

University of Kansas

X-Ray Emission in the Solar System

Draft
X-Ray Emission from the Terrestrial Magnetosheath
by Robertson and Cravens

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

The Results - X-Ray Images

Figure 1 shows soft X-ray volume emission rates in the x-z plane. The Earth is located at the origin. The x and R axis scales are in units of D, the subsolar distance to the magnetopause. The resolution is rather low (101 data points in both the x and z directions of the graph); however, it can clearly be seen that the maximum production rate is in the subsolar region. The boundaries of the magnetopause and shock are well-defined. Spreiter's plots provided no information for distances greater than 3 D downwind; consequently, our magnetosheath in the tailward direction is abruptly discontinued at that distance.

The volume emission rates were integrated along parallel paths of 100 R_E length for each of the 101 x 101 pixels in our simulated images (Figure 2). As expected, the sharp demarcation lines of the magnetopause and bow shock, apparent in Figure 1, are smoothed out in Figure 2, although they are still clearly discernible. Figure 2 also shows that X-ray emission can extend far out into the solar wind, but that the magnetosheath region has the greatest intensities. It is also evident from Figure 2 that the soft X-ray appearance of the magnetosheath depends on viewing angle.

Figure 1. X-ray production rate in the x-z plane. Rates are in eV cm^-3 s^-1. R is distance from the x-axis in this figure, and D is the radial distance to the subsolar magnetopause. Bow shock and magnetosphere positions are indicated.

Figure 2. Image of the X-ray intensity as observed from the Earth's flanks (left panel), and from an observation point 45 deg. from the Earth-Sun axis (right panel), in the equatorial plane. Units are keV cm^-2 s^-1 sr^-1. R and X are coordinates in the image plane. Bow shock and magnetosphere positions are again indicated.

Next: Results - Variable X-Ray Emission

Last modified January 21, 2004

Tizby Hunt-Ward
tizby@ku.edu

	Figure 1. X-ray production rate in the x-z plane. Rates are in eV cm^-3 s^-1. R is distance from the x-axis in this figure, and D is the radial distance to the subsolar magnetopause. Bow shock and magnetosphere positions are indicated.
	Figure 2. Image of the X-ray intensity as observed from the Earth's flanks (left panel), and from an observation point 45 deg. from the Earth-Sun axis (right panel), in the equatorial plane. Units are keV cm^-2 s^-1 sr^-1. R and X are coordinates in the image plane. Bow shock and magnetosphere positions are again indicated.