0.2X0.2 Aperture

Description

The "utility" slit for the echelle gratings. This slit is the most photometric of the supported echelle slits and has the highest throughput for photon statistics. Starting in Cycle 12, this slit is also supported for use with the first order gratings, and it is the recommended aperture for first order MAMA snapshot and survey programs that do not have a scientific need for a long-slit (see Section 2.9).


Table 13.25: 0.2X0.2 Throughputs.

λ

% Throughput

1200

54.5

1800

67.2

2400

73.7

3000

77.2

3600

79.6

4200

81.6

4800

82.6

5400

83.2

6000

81.7

Projected Length (arcsec)

Aperture

MAMA (E-modes)

Width (arcsec)

0.2X0.2

0.2

0.2

Figure 13.72: 0.2X0.2 Aperture Throughput as a Function of Wavelength.