31X0.05ND(A-C) Apertures

Description

Set of three supported neutral-density filtered slits for use with first-order or echelle observations. The approximate dex ND factors are 0.4, 0.8, and 1.2, for 31X0.05NDA, 31X0.05NDB, and 31X0.05NDC, respectively. Their use for PRISM observations is "available-but-unsupported" at this time.

Special Considerations

Observations with this slit require a PEAKUP prior to science observations. Use of these long slits with an echelle grating will cause order overlap problems (see Section 12.2), but for point sources the order separation may be adequate for many science programs.


Table 13.31: 31X0.05ND(A-C) Throughputs (%).

λ

31X0.05NDA

31X0.05NDB

31X0.05NDC

  1100

  3.6

0.9

0.09

  1150

  9.5

3.7

1.28

  1200

12.7

5.2

1.83

  1300

15.0

6.2

2.36

  1400

16.1

6.7

2.78

   1500

16.9

7.0

3.06

  1600

17.5

7.2

3.17

  1700

18.3

7.0

3.18

  1800

18.6

6.8

3.06

  1900

18.3

6.7

2.95

  2000

18.1

6.6

2.88

  2100

18.1

6.5

2.93

  2200

18.3

6.5

3.08

  2300

18.4

6.6

3.22

  2400

18.6

6.7

3.32

  2500

18.6

6.8

3.37

  2600

18.7

6.8

3.42

  2700

18.7

6.8

3.50

  2800

18.6

6.8

3.59

  2900

18.7

6.8

3.64

  3000

18.6

6.6

3.64

  3100

18.4

6.4

3.59

  4400

14.4

4.2

2.66

  8800

  8.7

2.6

1.61

12400

  4.4

1.3

0.80

Aperture    

Projected Length (arcsec) 

Width (arcsec)  

31X0.05NDA

31

0.048

31X0.05NDB

31

0.048

31X0.05NDC

31

0.048

Figure 13.80: 31X0.05ND(A-C) Aperture Throughput as a Function of Wavelength.