FP-SPLIT Slits
0.2X0.2FP(A-E) Apertures

Description

The FP-SPLIT slits consist of two sets of five slits-in each set the slits are all the same size. They are for use with the MAMA echelle gratings. It is possible to achieve high S/N data for bright targets, independently of the quality of the flat-field, by means of a special observing strategy wherein multiple spectrograms are obtained through these slits.

Special Considerations

See Chapter 12 for more details on obtaining high S/N spectral data.

Aperture	Projected Length (arcsec)	Width (arcsec)
0.2X0.2FPA	0.2	0.2
0.2X0.2FPB	0.2	0.2
0.2X0.2FPC	0.2	0.2
0.2X0.2FPD	0.2	0.2
0.2X0.2FPE	0.2	0.2

Figure 13.78: Schematic of the STIS Fixed-Pattern Slit Configuration. AXIS1 corresponds to the dispersion direction, and AXIS2 to the spatial direction. Dimensions are not to scale.

FP-SPLIT Throughputs

Table 13.30: 0.2X0.2FP(A-E) Slit Throughputs

	% Throughput
1200	54.7
1800	67.4
2400	73.9
3000	77.3
3600	79.7
6000	82.0

Figure 13.79: 0.2X0.2FP(A-E) Aperture Throughput as a Function of Wavelength