Table of Contents

Purpose 3
Document Conventions 4
Layout 4
NICMOS Proposal Preparation 7
The Help Desk at STScI 8
The NICMOS Instrument Team at STScI 8
Supporting Information and the NICMOS
Web Site 9

NICMOS is a New Instrument 12
Information Updates for Cycle 7-NICMOS 12
NICMOS Status Summary 13
Recommendation Summary 14
Supported NICMOS Capabilities for
Cycle 7-NICMOS 15

Instrument Capabilities 19
Instrument Design 20
Physical Layout 20
Dewar Anomaly 22
Imaging Layout 24
Camera 1 24
Camera 2 25
Camera 3 26
Placement and Orientation of Cameras 26
Comparison to WFPC2 and STIS 26
Basic Operations 27
Comparison to CCDs 29
Target Acquisition Modes 30
Attached Parallels 30
The Infrared Background 31
Conversion Between Fluxes and Magnitudes 35
Designing NICMOS Observations 35

Filters & Optical Elements 39
Nomenclature 40
Filter Sensitivity Curves 46
Out-of-Band Leaks in NICMOS Filters 48
Image Quality and Focus 49
Cameras 1 and 2 49
Camera 3 55
Field Dependence 61
Transient Bad Pixels 62
NICMOS Aperture Definitions 62
Aperture Definitions 63
NICMOS Coordinate System Conventions 63
Orients 64

Coronography 67
Coronographic Acquisitions 68
Reuse Target Offset and Interactive Acquisitions 69
Detector and Coronographic Hole Motion Issues 70
PSF Centering 70
Coronographic Decision Chart 71
Polarimetry 73
Instrumental Polarization 73
Theory 73
Polarimetry Decision Chart 75
Polarimetric Sensitivity 76
Grism Spectroscopy 78
Relationship Between Wavelength and Pixel 79
Multi-Object Spectroscopy 80
Grism Decision Chart 81
Sensitivity 83
Grism Analysis Software 87

Overview 89
Instrumental Factors 90
Calculating NICMOS Imaging Sensitivities 92
Signal to noise Calculation 92
Exposure Time Calculation 94
Software Tools 96
Filter Sensitivity Curves 96
Signal to Noise for a Source 96
Saturation and Detector Limitations 96
WWW Access to Imaging Tools 97
Examples 97
Using Exposure Time and Signal to noise Calculators 97
Examples of Calculations by Hand 101
NICMOS Grism Sensitivity on the Web 103

Physical Characteristics 105
Detector Response Curves 105
Detector Artifacts 107
Shading 107
Amplifier Glow 108
Read-Noise 108
Linearity and Saturation 109
Effects of Overexposure of the NICMOS Detectors 109
Effect of Cosmic Rays 110
Intra-Pixel Sensitivity Variations 110
Flat Field Response 111
Characteristics of the Flat Fields 111
Wavelength Variations-Details 113
Special Situations 116
Extended Sources with Extreme Spatial
Color Variations 118
Multi-Object Grism Spectroscopy 118

Introduction 119
Detector Resetting as a Shutter 121
Fast and Slow Readout Modes 121
Accumulate Mode 121
Multiple-Accumulate Mode 124
MULTIACCUM Predefined Sample Sequences
(SAMP-SEQ) 126
Trade-offs Between ACCUM and MULTIACCUM 128
Read Times and Dark Current Calibration in
ACCUM Mode 130
Acquisition Mode 130
NICMOS Science Data 132

Overview 133
NICMOS Exposure Overheads 134
Orbit Use Determination 136
Example 1: A Two-Chop Pattern Using Multi-Accum
and the Coronograph 136
Example 2: Polarization Observations Using a
Chop Pattern and MULTI-ACCUM 138
Example 3: Making a Map using Square-waVE-dith 138
Example 4: Changing Cameras and Pattern 139
Example 5: Another Example of Mapping 141

Introduction 145
Chopping and Dithering Strategies 147
Compact Objects 147
Extended Objects 148
Chopping and Dithering Patterns 149
Dither Patterns 150
Chop Patterns 151
Combined Patterns 152
Examples 153
Orienting Patterns 158
Phase II Proposal -Instructions for Patterns 158
Parameters 159
Types of Motions 159

Camera 1, Filter F090M 161
Camera 1, Filter F095N 162
Camera 1, Filter F097N 163
Camera 1, Filter F108N 164
Camera 1, Filter F110M 165
Camera 1, Filter F110W 166
Camera 1, Filter F113N 167
Camera 1, Filter F140W 168
Camera 1, Filter F145M 169
Camera 1, Filter F160W 170
Camera 1, Filter F164N 171
Camera 1, Filter F165M 172
Camera 1, Filter F166N 173
Camera 1, Filter F170M 174
Camera 1, Filter F187N 175
Camera 1, Filter F190N 176
Camera 2, Filter F110W 177
Camera 2, Filter F160W 178
Camera 2, Filter F165M 179
Camera 2, Filter F171M 180
Camera 2, Filter F180M 181
Camera 2, Filter F187N 182
Camera 2, Filter F187W 183
Camera 2, Filter F190N 184
Camera 2, Filter F204M 185
Camera 2, Filter F205W 186
Camera 2, Filter F207M 187
Camera 2, Filter F212N 188
Camera 2, Filter F215N 189
Camera 2, Filter F216N 190
Camera 2, Filter F222M 191
Camera 2, Filter F237M 192
Camera 3, Filter F108N 193
Camera 3, Filter F110W 194
Camera 3, Filter F113N 195
Camera 3, Filter F150W 196
Camera 3, Filter F160W 197
Camera 3, Filter F164N 198
Camera 3, Filter F166N 199
Camera 3, Filter F175W 200
Camera 3, Filter F187N 201
Camera 3, Filter F190N 202
Camera 3, Filter F196N 203
Camera 3, Filter F200N 204
Camera 3, Filter F212N 205
Camera 3, Filter F215N 206
Camera 3, Filter F222M 207
Camera 3, Filter F240M 208

Infrared Flux Units 209
Background 210
Units for NICMOS 211
Formulae 211
Converting Between Fn and Fl 211
Conversion Between Fluxes and Magnitudes 212
Conversion Between Surface Brightness Units 213
Look-up Tables and Software 213
Examples 220
Infrared Line Lists 220

Overview and New Features 231
Associations 232
Re-engineering 234
NICMOS Pipeline 234
Static Calibrations-calnica 234
Contemporaneous Observations-calnicb 237
NICMOS Data Products 238
Standard NICMOS Dataset Structure 238
IRAF Access 240

Expected Accuracies 243
Remarks 243
Areas of Significant Uncertainty 243
Provisional Cycle 7 Calibration Goals 244

Introduction 245
Thermal Vacuum Test 246
Servicing Mission Observatory Verification 246
Cycle 7 Calibration Program 247
Detector Performance 250
Flat Fields 250
Photometry 250
Thermal Background 251
Polarizers 251
Coronograph 252
Point Spread Function 252
Focus Monitoring 252
Photometric Calibration 252
Flux Standards for NICMOS Absolute Calibration 252
Ground Based Calibrations 254
References 255

Glossary 257
Appendix 261

Bright Object Mode 261
Ramp Mode 263
Using Ramp Mode to Reject Cosmic Rays and
Detect Saturation 266
Limitations of Ramp Mode 270

Index 273