Cosmic Origins Spectrograph Instrument Handbook for Cycle 17

Chapter 5:
Spectroscopy with COS

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5.1 The Capabilities of COS
    5.1.1 Signal-to-noise Considerations
    5.1.2 Photometric (Flux) Precision
    5.1.3 Spatial Resolution and Field of View
    5.1.4 Wavelength Accuracy
    5.1.5 Scattered Light in COS Spectra
    5.1.6 Spectroscopic Resolving Power
    5.1.7 Sensitivity
    5.1.8 Sensitivity to second-order spectra
5.2 Non-linear Photon Counting Effects (Dead-time Correction)
5.3 Exposure Time Considerations
5.4 Apertures
5.5 TIME-TAG or ACCUM?
    5.5.1 TIME-TAG Mode
    5.5.2 ACCUM Mode
5.6 FUV Gap Coverage and Single Segment Usage
5.7 Internal Wavelength Calibration Exposures
    5.7.1 Concurrent Wavelength Calibration with TAGFLASH
    5.7.2 AUTO Wavecals (When TAGFLASH is not Used)
    5.7.3 Wavelength Calibration Exposures with the BOA
    5.7.4 User-specified Wavelength Calibration Exposures
(GO Wavecals)
5.8 Achieving Higher Signal-to-noise using FP-POS
    5.8.1 Use of Optional Parameter FP-POS
    5.8.2 FUV Signal-to-noise
    5.8.3 NUV Signal-to-noise
5.9 EXTENDED Optional Parameter
5.10 Calibrations
    5.10.1 Internal Calibrations
    5.10.2 External Calibrations
5.11 Wavelength Settings and Ranges
    5.11.1 "Painting" a Complete NUV Spectrum