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Space Telescope Imaging Spectrograph
Imaging Bright Object Protection Limit

A few important points to note.


Table 14.40: MAMA Bright-Object limits (V magnitudes and cgs units). V magnitudes include NO additional safety factor to account for extrapolation uncertainties from the optical to the UV spectral range.
 
FUV-MAMA
NUV-MAMA
Spectral Type
25MAMA
F25SRF2
F25QTZ
F25LYA
25MAMA
F25SRF2
F25QTZ
F25CN182
F25CIII
F25CN270
F25MGII
Flat, point source1
9.6 × 10-15
1.7 × 10-14
5.1 × 10-14
4.5 × 10-13
2.1 × 10-15
2.4 × 10-15
2.5 × 10-15
2.5 × 10-14
1.9 × 10-13
1.6 × 10-14
8.5 × 10-14
Flat, extended, peak2
4.0 × 10-12
7.5 × 10-12
2.1 × 10-11
1.9 × 10-10
9.0 × 10-13
1.0 × 10-12
1.0 × 10-12
1.0 × 10-11
8.0 × 10-11
7.0 × 10-12
3.5 × 10-11
O5 V3
19.1
18.3
16.8
15.2
19.2
19.0
18.8
16.8
14.6
16.2
14.2
O7 V
18.9
18.1
16.6
15.0
19.1
18.9
18.7
16.7
14.5
16.1
14.2
O9 V
18.7
17.9
16.4
14.7
18.9
18.7
18.6
16.6
14.4
16.0
14.1
B0 V
18.6
17.8
16.3
14.6
18.8
18.7
18.5
16.5
14.3
16.0
14.0
B1 V
18.3
17.4
16.0
14.3
18.6
18.4
18.2
16.2
14.0
15.8
13.8
B3 V
17.4
16.7
15.3
13.3
17.9
17.8
17.7
15.5
13.3
15.3
13.4
B5 V
16.7
16.1
14.8
12.3
17.5
17.3
17.2
15.1
12.9
14.9
13.0
B8 V
15.5
15.1
13.8
10.6
16.7
16.6
16.5
14.3
12.1
14.2
12.3
A1 V
13.3
13.0
12.3
7.2
15.6
15.5
15.5
13.1
11.0
13.3
11.5
A3 V
12.1
11.9
11.5
5.4
15.4
15.3
15.2
12.8
10.8
13.1
11.3
A5 V
10.7
10.6
10.4
3.4
15.1
15.0
15.0
12.4
10.4
12.9
11.1
F0 V
8.5
8.3
8.3
0.9
14.6
14.5
14.4
11.5
9.4
12.5
10.7
F2 V
7.7
7.5
7.4
0.0
14.3
14.2
14.2
11.1
8.9
12.3
10.6
F5 V
5.8
5.7
5.6
-2.0
13.9
13.8
13.8
10.3
8.0
12.0
10.3
F8 V
4.7
4.6
4.5
<-2.0
13.7
13.6
13.5
9.8
7.4
11.7
10.1
G2 V4
4.8
3.9
3.6
1.4
12.9
12.8
12.8
8.7
6.5
11.1
9.7
G8 V5
4.2
3.3
3.0
0.8
12.5
12.4
12.4
8.1
6.0
10.7
9.4
K2 V6
5.7
3.9
3.2
2.6
11.8
11.7
11.7
7.2
5.6
9.9
9.2
KM III7
4.2
3.6
2.5
1.1
11.5
11.4
11.4
6.9
5.6
9.5
8.9
Integrated V magnitude8
13.4
12.6
11.2
9.6
13.5
13.3
13.1
11.2
8.9
10.5
8.5
Flat, extended, all detector9
7.2 × 10-15
1.4 × 10-14
4.1 × 10-14
3.6 × 10-13
1.7 × 10-15
1.9 × 10-15
2.0 × 10-15
2.0 × 10-14
1.5 × 10-13
1.3 × 10-14
6.7 × 10-14
1Maximum allowed flux for a point source in erg s-1 cm-2 -1.
2Maximum peak allowed flux for an extended source in erg s-1 cm-2 -1 arcsec-2.
3V magnitude limit for unreddened single stars. O5 V through F8 V are based on Kurucz models.
4The magnitudes listed for G2 V are for the Solar template in the STIS ETC.
5The magnitudes listed for G8 V are from IUE data for the star Tau Ceti.
6The magnitudes listed for K2 V are from IUE data for the star Epsilon Eri.
7The magnitudes listed for KM III are from IUE data for 9 stars of these types.
8Maximum integrated V magnitude for stars in the field assuming all are of O5 V spectral type.
9Maximum allowed flux for an extended source which covers the full detector in erg s-1 cm-2 -1 arcsec-2