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Cosmic Origins SpectrographInstrument Handbookfor Cycle 22 > Chapter 13: Spectroscopic Reference Material > FUV Grating G160M

FUV Grating G160M
Description
The G160M grating samples wavelengths between about 1405 and 1775 . It offers higher resolution and effective area than the G140L grating, but less spectral coverage.
Special Considerations
The gap between segments A and B spans 18.1 . To fill this gap requires exposures separated by two central-wavelength settings.
Resolving
Power
R = λ/Δλ
Dispersion
(m pixel–1)
FP-POS
Step
( step-1)
Figure 13.11: Wavelength Ranges for the G160M Grating
G160M Point-Source Sensitivity
Table 13.6: G160M Point-Source Sensitivity for PSA
Sensitivity
(counts pixel-1 sec-1 per
erg cm-2 sec-1 -1)
Figure 13.12: G160M Point-Source Sensitivity for PSA and BOA
G160M Signal-to-Noise Ratio
Figure 13.13: Point-Source Signal-to-Noise as a Function of STMAG for G160M at 1610
The top axis displays constant Fλ values corresponding to the STMAG units (V+STMAGλ) on the bottom axis. Recall that STMAG = 0 is equivalent to Fλ = 3.63E-9 erg cm-2 s-1 -1. Colors refer to exposure times in seconds. The edge of the shaded area corresponds to the bright-object screening limit. Use of the PSA is assumed.

Cosmic Origins SpectrographInstrument Handbookfor Cycle 22 > Chapter 13: Spectroscopic Reference Material > FUV Grating G160M

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