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XMM-Newton Guest Observer Facility

XMM-NEWTON Solar Wind Charge Exchange/Soft Proton Tool

This form takes as input either an observation number (ObsID) or an XMM-Newton revolution number (Orbit number).

Diagnostic plots are returned indicating the likelihood of solar wind charge exchange and soft proton contamination for the selection.

N.B. The Orbit input will override the Observation input
A list of currently available trend files is available covering most of the Orbits 0-1999.

The output page will contain links to download the PDF files showing:
  • Wire Plot of the SWCX of the orbit
  • Wire Plot of the SWCX of the observation
  • These plots show the relative locations of the spacecraft, the line of sight, and the magnetosheath within a cube centered on the earth. The three-dimensional coordinate grid is in GSE coordinates where the positive X axis points towards the sun and the Z axis is perpendicular to the ecliptic plane. The dashed lines show the location of the nominal magnetosheath where "nominal" assumes a magnetopause standoff distance of 10 R_e and a bowshock standoff distance of 12.69 R_e. The solid black curves represent the orbit of the space, both in three dimensions and its projection on the GSE-X,GSE-Y plane; these two curves are connected at their end points. The dotted black line (which may appear solid) represents the intersection of the line of sight with the GSE-X,GSE-Y plane. The curves plotted in a single solid color represent the intersection of the line of sight with the cube centered on the earth; the color changes where that intersection moves from one cube face to another.

    As the solid wind flux varies, the size, shape, and density of the magnetosheath changes. The length of the straight colored lines represents the intersection of the line of sight with the magnetosheath while the color represents the product of the exospheric neutral density, the solar wind ion density in the magnetosheath, and the relative velocity of the two. This is essentially the emissivity divided by the cross-section and the abundance of the emitting species. Purple/blue are low emissivities which orange/brown are high emissivities.

    The magnetospheric model used is that of Spreiter et al. () which assumes that the shape of the magnetosheath does not change with the solar wind pressure though the stand-off distances, densities, and velocities do. The solar wind pressure used to scale the Spreiter model is that measured by the ACE satellite at L1 time-shifted to the nominal standoff distance. The exospheric model is an r^{-3} model with a density of 25 cm^{-3} at 10.0 R_e.

  • Light Curve Plot of the orbit
  • Light Curve Plot of the observation
  • These plots show the measured X-ray flux with time compared to our model magnetosheathic emission and several interesting solar wind parameters.

    MOS1: The low energy band (400-750 keV) flux is plotted with boxes while the high energy band (2000-7200 keV) flux is plotted with diamionds. The low energy band may be affected by charge exchange emission while the high energy band is very unlikely to be affected. The data have been binned to 640 s. Time intervals effected by soft proton flares have been removed. The flux has been accumulated from the entire field of view, so if there is a temporally variable object in the field of view, that variation will be reflected in this plot.

    MOS2: The same quantities as above, but plotted for the MOS2.
    PN: The same quantities as above, but plotted for the PN.

    Magnetospheric SWCX: The scaled charge exchange emissivity integrated along the line of sight through the magnetosheath. The plotted quantity is the neutral exospheric density multiplied by the solar wind proton density and the relative velocities. One would have to multiply this quantity by the abundance of the species of interest and the cross-section to obtain a true emissivity.

    Solar Wind Protons: The solar wind proton density (cm^{-3}$) and the solar wind proton velocity (km/s/100).

    Solar Wind Abundances: The red boxes are the He/proton ratio (multiplied by ten) the green curve is the C^{+6}/C^{+5} ratio, and the blue curve is the O^{+7}/O^{+6} ratio.

  • Count Rate Histogram plots of the Observation

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This file was last modified on Thursday, 08-Mar-2012 16:16:40 EST
Curator:Michael Arida (ADNET);

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