has two central wavelength settings optimized to cover the optical through the far-ultraviolet (FUV) tail down to 1150 Å. It is used with the NUV-MAMA
The full dispersion spreads over ~450 pixels
with dispersion as shown in Figure 13.64
; thus if you have sources covering the field of view in the dispersion direction, the red tail will be lost for some targets with this setting. For a plot of wavelength vs. pixel no., see Figure 4.12
We note that the dispersion of the PRISM at
wavelengths longer than ~2600 Å is very poorly known at this time.
Point source sensitivity assumes full transmission (zero slit losses). Diffuse source
sensitivity assumes a 0.1” wide slit. To convert point source sensitivities to diffuse source sensitivities multiply the point source values by the grating spatial (cross dispersion) plate scale in units of arcseconds per pixel and by the width of the desired slit in units of arcseconds.