Space Telescope Imaging Spectrograph Instrument Handbook for Cycle 17

FP-SPLIT Slits
0.2X0.06FP(A-E) Apertures

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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. Observations with this slit require a prior PEAKUP.

Aperture	Projected Length (arcsec)	Width (arcsec)
0.2X0.06FPA	0.2	0.06
0.2X0.06FPB	0.2	0.06
0.2X0.06FPC	0.2	0.06
0.2X0.06FPD	0.2	0.06
0.2X0.06FPE	0.2	0.06

Figure 13.76: 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 13.29: Throughput for 0.2X0.06FP(A-E)

	% Throughput
1200	24.8
1800	53.7
2400	60.5
3000	63.1
3600	63.8
4200	63.7
4800	62.5
5400	60.7
6000	58.0

Figure 13.77: 0.2X0.06FP(A-E) Aperture Throughput as a Function of Wavelength