F25CN270 - NUV-MAMA

Description

The F25CN270 filter with the NUV-MAMA provides medium bandwidth imaging near the Mg II 2798 Å feature.

Recommended Uses

This filter is recommended for imaging Mg II 2798 Å line emission and its local continuum.

Special Considerations

There is a substantial red leak in this filter. Sources with a red underlying continuum may be difficult to observe. Users should be careful to take into account the underlying continuum in estimating whether the observation will fall within the bright object protection limits.


Pivot λ (Å)

FWHM (Å)

AB mag zero point

Speak

Bλ

R80 (arcsec)

Flux in central pixel

2710.9

161.8

21.360

1.17e+14

202.3

0.17

14%



Figure 14.50: F25CN270 NUV-MAMA Integrated System Throughput and Red Leak




Table 14.20: F25CN270 NUV-MAMA Sensitivity & Throughput

λ

Sensitivity

% Throughput

2575.

6.70E12

0.11

2600.

6.37E13

1.08

2625.

8.19E13

1.37

2650.

1.01E14

1.67

2675.

1.13E14

1.86

2700.

1.12E14

1.82

2725.

1.10E14

1.77

2750.

8.70E13

1.39

2775.

9.22E13

1.46

2800.

9.81E13

1.54

2825.

6.27E13

0.97

2850.

1.40E13

0.21



Figure 14.51: Point Source S/N vs. AB magnitude in the V-band for the F25CN270 NUV-MAMA mode. Curves are labeled by required exposure time (seconds).




Figure 14.52: Extended Source S/N vs. AB magnitude in the V-band for the F25CN270 NUV-MAMA mode. Top curves are for an area of 0.2 arcsec2; bottom curves are for 1 arcsec2. Average sky assumed. Curves are labeled by required exposure time (seconds).




Table 14.21: Radial Profile for F25CN270*

Radius


 

Fraction of Energy Encircled

Pixels

Arcsec

Intensity

1

0.024

5.158e-02

0.240

1.5

0.037

2.953e-02

0.378

2

0.049

1.608e-02

0.504

3

0.073

5.260e-03

0.643

4

0.098

2.022e-03

0.708

5

0.122

1.215e-03

0.750

10

0.245

2.048e-04

0.854

15

0.367

9.848e-05

0.908

20

0.490

4.138e-05

0.942

25

0.613

1.817e-05

0.960

30

0.735

1.440e-05

0.974

40

0.980

4.656e-06

0.994

* See STIS ISR 2003-01.


Figure 14.53: Point Source Encircled Energy for F25CN270 NUV-MAMA




Figure 14.54: Point Source Intensity vs. Radius for F25CN270 NUV-MAMA