Table of Contents

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Preface

Cosmic Origins Spectrograph

1. Overview

1.1 Instrument Overview

1.2 STScI Contact Information

1.3 The COS Instrument Definition Team

1.4 Handbook Information and Additional Resources

2. Instrument Description

2.1 Detectors

2.2 Spectroscopic Modes

2.3 Apertures

2.4 Photon Event Counting and Spectrum Accumulation

2.5 Calibration Observations

2.6 Signal-to-Noise Considerations

2.7 Observing Non-Point Sources

3. Throughputs and Sensitivities

3.1 Throughputs and Effective Areas

3.2 Point Source Sensitivities

3.3 Bright Limits

3.4 Backgrounds

4. Choosing Between COS and STIS

4.1 General Considerations

4.2 Recommended Choices

5. Target Acquisitions