The PR110L prism is sensitive to below 1200 Å and includes the geo-coronal Lyman-alpha line, so it is subject to high background. The dispersion at Lyman-alpha is 2.6 Å per pixel. Figure 6.22 shows the sensitivity with wavelength and the wavelength width of the pixels. The long wavelength cut-off of the CsI MAMA detector at ~1800 Å occurs before the long wavelength build-up of flux; the dispersion at 1800 Å is 21.6 Å/pixel. However the detected counts at the long wavelength edge must be within the MAMA Bright Object Protection Limits (BOP) (see Section 4.6). These limits must include the contribution of the geo-coronal Lyman-alpha flux per SBC pixel. The numbers in Figure 6.22 indicate the resolving power (R) and the offset from the direct image in pixels (x) as functions of wavelength. The direct and prism images use distinct apertures with a small angle maneuver between them.
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