WFPC2 Instrument Handbook for Cycle 10

Contents

Acknowledgments

Contents

Chapter 1: Introduction

Instrument Overview

Field-of-View

Spectral Filters

Quantum Efficiency and Exposure Limits

CCD Detector Technology

UV Imaging

Aberration Correction and Optical Alignment

Which Instrument to Use: WFPC2, ACS, NICMOS, or STIS?

Comparison of WFPC2 and ACS

Comparison of WFPC2 and NICMOS

Comparison of WFPC2 and STIS

History of WFPC2

The Previous vs. Current Generation: WF/PC-1 vs. WFPC2

Organization of this Handbook

What's New in Version 5.0 for Cycle 10

WFPC2 Handbook on the WWW

The Help Desk at STScI

Further Information

Chapter 2: Instrument Description

Science Objectives

WFPC2 Configuration, Field-of-View, and Resolution

Overall Instrument Description

Quantum Efficiency

Shutter

Serial Clocks

Overhead Times

CCD Orientation and Readout

Calibration Channel

Chapter 3: Optical Filters

Introduction

Choice of Broad Band Filters

Linear Ramp Filters

Spectral Response

Target Locations

LRF Photometric Calibration

Redshifted [OII] Quad Filters

Polarizer Quad Filter

Polarization Calibration

Methane Quad Filter

Wood's Filters

Red Leaks in UV Filters

Apertures

Chapter 4: CCD Performance

Introduction

Quantum Efficiency

Dynamic Range

Bright Object Artifacts

Blooming

Horizontal Smearing

Diffraction Effects and Ghost Images

Residual Image

Quantum Efficiency Hysteresis

Flat Field Response

Dark Backgrounds

Sources of Dark Current

Darktime

Dark Current Evolution

Cosmic Rays

SAA and Scheduling System Changes

Radiation Damage and Hot Pixels

Photometric Anomalies: CTE and Long vs. Short

Charge Transfer Efficiency

The Long vs. Short Photometric Anomaly

Read Noise and Gain Settings

Chapter 5: Point Spread Function

Effects of OTA Spherical Aberration

Aberration Correction

Wavefront Quality

CCD Pixel Response Function

Model PSFs

PSF Variations with Field Position

Aperture Corrections vs. Field Position

PSF Variations with Time / OTA Focus

PSF Anomaly in F1042M Filter

Large Angle Scattering

Ghost Images

Optical Distortion

Chapter 6: System Throughput and SNR / Exposure Time Estimation

System Throughput

On-Line Exposure Time Calculator

Target Count Rates

Count Rates for Stellar Sources

Count Rates for Power Law Sources

Count Rates for Emission Line Sources

Sky Background

Signal-to-Noise Ratio Estimation

Point Sources -- PSF Fitting

Point Sources -- Aperture Photometry

Extended Sources

Exposure Time Estimation

Sample SNR Calculations

Point Sources

Extended Sources

Emission Line Sources

Photometric Anomalies

Red Leaks in UV Filters

Long-term Photometric Stability

Short-term Time Dependence of UV Response

Chapter 7: Observation Strategies

Observing Faint Targets

Observing Bright Targets

Observing Faint Targets Near Bright Objects

Cosmic Rays

Choosing Exposure Times

Dithering with WFPC2

Dither Strategies

Analysis of Dithered Data

Pointing Accuracy

Absolute Pointing Accuracy

Updates to Aperture / Coordinate Systems

Pointing Repeatability

Tracking Modes

CCD Position and Orientation on Sky

Polarization Observations

Observing with Linear Ramp Filters

Emission Line Observations of Galaxy Nuclei

Chapter 8: Calibration and Data Reduction

Calibration Observations and Reference Data

Flat Fields

Dark Frames

Bias Frames

Data Products and Data Reduction

Pipeline Processing

Fluxes and Standard Magnitudes

Color Transformations of Primary Filters

Calibration Plan Summary

Cycle 4 Calibration Plan

Internal Monitors

Photometric Monitors

Earth flats

Cycle 5 Calibration Plan

Cycle 6 Calibration Plan

Cycle 7 Calibration Plan

Introduction

Overview

Cycle 8 Calibration Plan

Introduction

Overview

Cycle 9 Calibration Plan

Calibration Accuracy

Appendix 1: Passband Plots

Filter Passbands, with and w/out Total System

F122M, F130LP, F160BW

F165LP, F170W, F185W

F218W, F255W, F300W

F336W, F343N, F375N

F380W, F390N, F410M

F437N, F439W, F450W

F467M, F469N, F487N

F502N, F547M, F555W

F569W, F588N, F606W

F622W, F631N, F656N

F658N, F673N, F675W

F702W, F785LP, F791W

F814W, F850LP, F953N

F1042M, FQUVN-A, FQUVN-B

FQUVN-C, FQUVN-D, FQCH4N-A

FQCH4N15-B, FQCH4N33-B, FQCH4N-C

FQCH4N-D, Parallel and Perpendicular Polarizers

Normalized Passbands including -System Response

Appendix 2: Point Source SNR Plots

Plots for Estimating Point Source SNR

Acronyms

References

References

Instrument Science Reports

Technical Instrument Reports

Other Selected Documents

The WFPC2 Clearinghouse

Index