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Hubble Space Telescope Wide Field and Planetary Camera HUBBLE SPACE TELESCOPE WIDE FIELD AND PLANETARY CAMERA 2 INSTRUMENT HANDBOOK \ Version 2.0 May 1994 , 'tJ ,It"",,. -:,. � i.. ,. Ii" o¢ .. WfPC21nsttu1/fentHtlndbook Ve rsion 2. 0 1 May 1994 Revision History Instrument Version Date Editor " WFIPC-1 1.0 October 1985 Richard Griffiths t WFIPC-1 2.0 May 1989 Richard Griffiths WFIPC-1 2.1 May 19.90 Richard Griffiths .� WFIPC-1 3.0 April 1992 John W. MacKenty WFPC2 1.0 March 1993 Christopher 1. Burrows WFPC2 2.0 May 1994 Christopher J. Burrows t Authors Christopher J. Burrows, Mark Oampin, Richard E. Griffiths, John Krist, John W. MacKenty with contributions from Sylvia M. Baggett, Stefano Casertano, Shawn P. Ewald, Ronald 1. Gilliland, Roberto Gilmozzi, KeithHorne, Christine E. Ritchie, Glenn Schneider, William B. Sparks, and lisaE. Walter and the WFPC2 IDT: John T. Trauger, Christopher J. Burrows, John Oarke, David Crisp, John Gallagher, Richard E. Griffiths, J. Jeff Hester, John Hoessel, John Holtzman, Jeremy Mould, and James A. Westphal. t In publications please refer to this document as "Wide Field and Planetary Camera 2 InstrumentHa ndbook, C. J. Burrows (Ed.), STScIpub lication(May 1994)" CAUTION The procedures for creating a Phase II proposal are being reviewed and revised as this is written. We strongly recommend that users check the Phase II documentation carefully. We also recommend checking on STEIS at that time for a revised version of this Instrument Handbook; Some significant uncertainties remain concerning the WFPC2 performance. Updated information will be posted as it becomes available. The Space Telescope Science Institute is operated by the Association of Universities for Research in Astronomy, Inc., for the National Aeronautics and Space Administration. ii WF.PC2In strumentHa ndbook Ve rsion 2.0 1 May 1994 Table of Contents 1. INTR.ODUCTION......................................................... ................................................... 1 1.1. Background to the WFPC2 ................................................................. ........ 1 1.2. Science Performance. .................................................................................. 1 1.3. Calibration plans.......................................................................................... 2 1.4. Major Changes in WFPC2........................................................................... 2 1.4.1. Single Field Format............................................................ ; ........ 2 1.4.2. Optical Alignment Mechanisms............................................... 3 1.4.3. CCD Technology.......................................................................... 4 1.4.4. UV Imaging................................................................................... 5 1.4.5. Calibration Channel.................................................................... 5 1.4.6. Spectral Elements ....................................................................... 5 1.5. Organization of this Handbook ............................................................... :6 1.6. References ............................................ .........................................................6 2. INSTRUMENTDESCRIPTION .. .................................................................................... 7 2.1. Science Obj ectives ....................................................................................... 7 2.2. WFPC2 Configuration, Field of View and Resolution .......................... 7 2.3. Overall In.strument Description................................................................ 8 2.4. Quantum. Efficiency.. .................................................................................... 11 2.5. Shutter ............................................................................................................ 12 2.6. Overhead times............................................................................................ 13 2.7. CCD Orientation and Readout .................................................................. 14 3. OYTICALFIL'fERS ....................................................................................� .................... 16 3.1. Choice Of Broad Band Filters .................................................................... 20 3.2. linear RampFilters ..................................................................................... 20 3.2.1. SpectralResponse ....................................................................... 21 3.3. Redshifted [Om Qu ad Filters ....................................................................27 3.4. Polarizer Quad Filter................................................................................... 27 3.5. Methane Quad .............................................................................................. 30 3.6. Wood's Filters ............................................................................................... 32 3.7. Apertures ....................................................................................................... 33 4. CCD PERFORMANCE.. .............. .................................................................................... 35 4.1. In.troduction..................................................... ............................................. 35 4.2. CCD Characteristics... ................................................................................. 36 4.2.1. Qu antum.Efficiency .................................................................... 36 4.2.2. DYIlamic Range . .......................................................................... 37 iii WfPC2 Instrument Handbook Ve rsion 2. 0 1 May 1994 4.2.3. Bright Obj ect Artefacts .............................................................. 38 4.2.4. Residual Image............................................................................ 39 4.2.5. Qu antum Efficiency Hysteresis ...............................................40 4.2.6. FlatField .......................................................................................40 4.2.7. Dark Noise ....................................................................................41 4.2.8. Cosmic Rays .................................................................................42 4.2.9. Radiation Damage...................................................................... 45 4.2.10. Charge Transfer Efficiency .....................................................45 4.2.11. Read Noise and Gain Settings ................................................45 4.2.12. CCD Electronics ........................................................................46 4.3. References .....................................................................................................46 5. POINT SPREAD FUNCTION .........................................................................................47 5.1. Effects of OTA Spherical Aberration .......................................................47 5.2. CCD Pixel Response Function ...................................................................48 5.3. Model PSFs ....................................................................................................49 5.4. Aberration correction. ................................................................................ 52 5.5. Wavefront Quality........................................................................................ 53 5.6. Optical Distortion........................................................................................ 53 6. EXPOSURE TIME ESTIMATION................................................................................... 55 6.1. System Throughput..................................................................................... 55 6.2. Sky Background............................................................................................ 58 6.3. Point Sources ................................................................................................ 58 6.4. Extended Sources ......................................................................................... 59 6.5. Color Transformations of Primary Photometric Filters ...................... 60 6.6. Red Leaks in UV Filters ..............................................................................62 7. CALIBRATIONAND DATA REDUCTION .................................................................64 7.1. Calibration Observations and Reference Data ......................................64 7.2. In.strument Calibration............................................................................... 64 7.3. Flat Fields...................................................................................................... 64 7.4. Dark Frames ..................................................................................................65 7.5. Bias Frames................................................................................................... 65 7.6. Data Reduction and Data Products .........................................................65 7.7. Pipeline Processing ...................................................................................... 65 7.8. Data Formats................................................................................................ 66 ACRONYMliST ................................................................................................................. 67 iv WfPC2 InstrumentHa ndbook Ve rsion 2. 0 1 May 1994 8. APPENDIX ......................................................................................................................
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