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Neutrals passing through the deflection system hit a 32 sided cone target with a grazing (20) angle of incidence. A MCP stack in the Z configuration detects the particles leaving the target block with 32 anodes. The signal from the MCP gives the direction of the primary incoming neutral. The MCP operates in ion mode with a negative bias of -3.0 kV and thus detects (a) sputtered ions of the target material, (b) ions resulting from stripping of the primary neutrals, and (c) neutrals reflected from the target surface. In order to improve the angular resolution and collimate the particles leaving the interaction surface, 32 separating walls are attached to the target forming a star-like structure. NPI covers 4p in one instrument scan and produces an image of the ENA distribution in the form of an azimuth x elevation matrix. To suppress the UV flux he NPI target uses the same coating as in the PIPPI and ASPERA-C experiments, namely, DAG 213, a resin - based graphite dispersion.
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