Contents

• • 1.1 Scope
  • 1.2 The Basic Scheme
  • 1.3 Organization of this Guide
  • 1.4 How to Use this Guide
  • 1.5 New Releases, Bug Fixes, Other Updates
    • 1.5.1 ASCA GOF Homepage
    • 1.5.2 Ascanews
  • 1.6 ASCA Newsletters
  • 1.7 Calibration Uncertainties
  • 1.8 Obtaining Help and Information, Reporting Bugs, Submitting Comments
    • 1.8.1 ascahelp
    • 1.8.2 Ftoolshelp and Xanprobs
  • 2.1 Introduction
  • 2.2 FITS Files
    • 2.2.1 Why FITS?
    • 2.2.2 FITS User's Guide
    • 2.2.3 OGIP Standard
  • 2.3 Data Processing Versions
  • 2.4 Three Levels of ASCA Data Files
  • 2.5 Basic File Structure
  • 2.6 Important Keywords and Columns in ASCA FITS Events Files
    • 2.6.1 RAWX/Y, DETX/Y, X/Y Columns and RA/DEC_NOM Keywords
    • 2.6.2 TIME Column and TIMESYS, MJDREF, TSTART, TSTOP Keywords
    • 2.6.3 GIS PHA, PI Columns
    • 2.6.4 GIS RISE_TIME, RTI Columns
    • 2.6.5 GIS MPC Mode Files
    • 2.6.6 SIS PHA, PHAS, GRADE, PI Columns
  • 2.7 MKF Files
  • 2.8 Housekeeping Files
  • 3.1 Introduction
  • 3.2 Description of GIS Modes
    • 3.2.1 PH mode
    • 3.2.2 MPC mode
  • 3.3 Imaging with the GIS
  • 3.4 GIS Mode-Dependent Keywords
  • 3.5 GIS Gain Determination
    • 3.5.1 Recalculate GIS Gain Using the Latest Calibration
    • 3.5.2 Manual Adjustment of the GIS Gain
  • 3.6 Other Issues Related to GIS Data
  • 4.1 Introduction
  • 4.2 Description of SIS Modes
    • 4.2.1 CCD Clocking Modes
    • 4.2.2 CCD Data Modes
  • 4.3 Summary of Issues Related to SIS Data
  • 4.4 Hot and Flickering Pixels
    • 4.4.1 Removing Hot and Flickering Pixels
    • 4.4.2 Event Threshold and Level Discrimination
    • 4.4.3 Light Leak and Address Discrimination
  • 4.5 Analyzing BRIGHT Mode Data, Grade and PI
    • 4.5.1 Classification of Events and Grade
    • 4.5.2 SIS PI
    • 4.5.3 Using SIS PI
  • 4.6 Analyzing FAINT and BRIGHT2 Mode Data, Echo, and DFE
    • 4.6.1 Echo Effect
    • 4.6.2 Dark Frame Error
    • 4.6.3 Combining FAINT and BRIGHT Modes Using FAINTDFE
  • 4.7 Non-uniform CTI
  • 4.8 Residual Dark Distribution (RDD)
    • 4.8.1 RDD Correction
  • 4.9 Event Threshold and 2-pixel Events
  • 4.10 Analyzing FAST Mode Data and Address Discrimination
    • 4.10.1 Address Discrimination
    • 4.10.2 How to Analyze FAST Mode Data
    • 4.10.3 Hot and Flickering Pixels in FAST mode
    • 4.10.4 FAST Mode Light Curves
    • 4.10.5 Potential Problems Peculiar to FAST Mode
  • 4.11 SIS Field of View
  • 4.12 SIS Mode-Dependent Keywords
  • 5.1 Introduction
  • 5.2 Screening Criteria Common to the GIS and SIS
    • 5.2.1 Elevation Angle (ELV)
    • 5.2.2 Stable Pointing Directions (ACS, ANG_DIST)
    • 5.2.3 South Atlantic Anomaly (SAA)
    • 5.2.4 Cut-off Rigidity (COR)
  • 5.3 GIS Screening Criteria
    • 5.3.1 Characteristics of GIS Internal Background
    • 5.3.2 Screening Based on Event Locations and Rise Time
    • 5.3.3 Summary
  • 5.4 SIS Screening Criteria
    • 5.4.1 Removing Hot and Flickering Pixels
    • 5.4.2 Grade Selection
    • 5.4.3 Bright Earth Angles (BR_EARTH)
    • 5.4.4 Events Above Threshold
    • 5.4.5 Avoiding Telemetry-Saturated Frames
    • 5.4.6 Time after passing through the South Atlantic Anomaly
    • 5.4.7 Time after passing through the Day-Night Terminator
    • 5.4.8 T_SAA and T_DY_NT WARNING for FTOOLS v3.6
    • 5.4.9 Summary
  • 5.5 Standard screening criteria used in GSFC REV1 processing
    • 5.5.1 GIS and SIS
    • 5.5.2 GIS only
    • 5.5.3 SIS only
  • 6.1 Introduction
  • 6.2 The Basics of Screening
    • 6.2.1 Screening Using XSELECT, ASCASCREEN or TKASCASCREEN
  • 6.3 Suggested Screening Strategies
  • 6.4 ASCASCREEN
    • 6.4.1 Before You Begin
    • 6.4.2 About ASCASCREEN
    • 6.4.3 Running ASCASCREEN
    • 6.4.4 After Running ASCASCREEN
    • 6.4.5 The -q Option
  • 6.5 TKASCASCREEN
  • 6.6 XSELECT
    • 6.6.1 Getting Acquainted
    • 6.6.2 Before You Begin
    • 6.6.3 Running XSELECT
    • 6.6.4 Displaying mkf Parameters
  • 7.1 Introduction
  • 7.2 The Basics of Filtering
  • 7.3 Region Filters
    • 7.3.1 Using SAOimage to Create Region Filters
  • 7.4 More About Region Filters
  • 7.5 Time Filters
    • 7.5.1 Time Filtering with the Mouse Cursor
    • 7.5.2 Time Filtering with the Keyboard
    • 7.5.3 Time Filtering with Files
    • 7.5.4 How Time Filter Files Are Combined
  • 7.6 Energy Filters
  • 7.7 Intensity Filters
  • 7.8 Phase Filters
  • 7.9 Energy-to-Channel Conversion
    • 7.9.1 GIS PH Mode
    • 7.9.2 SIS FAINT and BRIGHT2 Modes
    • 7.9.3 SIS BRIGHT and FAST Modes
  • 7.10 Using Region Filters From Other Missions
    • 7.10.1 SAOimage Region Files
    • 7.10.2 Converting Coordinates In Region Files
    • 7.10.3 Example: Using a ROSAT PSPC Region for the ASCA GIS
  • 8.1 Extracting Spectra
  • 8.2 Spectral Files
    • 8.2.1 Primary Header
    • 8.2.2 The Weighted Map (WMAP)
    • 8.2.3 Spectrum, Quality and Grouping Flags
    • 8.2.4 Spectrum GTI
  • 8.3 Binning and Grouping
    • 8.3.1 Binning
    • 8.3.2 Grouping
  • 8.4 Spectral Responses
  • 8.5 Obtaining GIS RMFs from the Calibration Database
  • 8.6 Generating SIS RMFs
  • 8.7 Generating ARFs with ASCAARF
    • 8.7.1 Standard Method - Using Standard XRT Calibration Files
    • 8.7.2 Ray-tracing Method
  • 8.8 Background Subtraction
    • 8.8.1 Blank-Sky Observations
    • 8.8.2 GIS Night Earth Observations
    • 8.8.3 How to Subtract Background
    • 8.8.4 Using Blank-Sky Data for BRIGHT2 Mode Spectra
  • 8.9 Analyzing SIS Spectra from Two or More Chips
  • 8.10 Combining Spectral Files
    • 8.10.1 For GIS
    • 8.10.2 For SIS
    • 8.10.3 Computing the Correct Background Normalization for Combined Spectra
  • 8.11 GIS Deadtime Correction
  • 8.12 How to Cope with SIS Pile-up Problem
  • 8.13 Getting Started with XSPEC
    • 8.13.1 Entering Data into XSPEC
    • 8.13.2 Ignoring Channels and Energy Ranges
    • 8.13.3 Defining Models
    • 8.13.4 Fitting Models
    • 8.13.5 Deriving Errors
    • 8.13.6 Plotting Results
  • 9.1 Introduction
  • 9.2 Three Formats of Light Curve and How to Extract Them
  • 9.3 Event Lists as Light Curves
  • 9.4 FITS Rate Files
  • 9.5 QDP (ASCII) Rate Files
  • 9.6 Creating Light Curve Figures with XSELECT
  • 9.7 Background Subtraction for Light Curves
  • 9.8 GIS Light Curve Deadtime Correction
  • 9.9 Telemetry Saturation Effects for SIS Data
  • 9.10 Barycentric and Geocentric Corrections
  • 9.11 GIS Light Curves Using Monitor Counts
  • 9.12 Temporal Resolution
    • 9.12.1 GIS PH Mode
    • 9.12.2 GIS MPC Mode
    • 9.12.3 SIS FAINT, BRIGHT and BRIGHT2 Modes
    • 9.12.4 SIS FAST Mode
  • 10.1 Introduction
  • 10.2 Extracting Images
  • 10.3 Image Files
  • 10.4 Attitude Reconstruction
    • 10.4.1 Pointing Stability
    • 10.4.2 Reconstruction Algorithm
  • 10.5 Exposure Maps
    • 10.5.1 Example ASCAEXPO Session
    • 10.5.2 HINTS on running ASCAEXPO and using its products
  • 10.6 The ASCA PSF
  • 10.7 Extended Sources and Spatio-Spectral Analysis
    • 10.7.1 Spatio-Spectral Analysis
  • 10.8 Merging Observations
  • 10.9 Image Deconvolution
  • 10.10 Getting Started with XIMAGE
  • 11.1 Acronyms
  • 11.2 Software Packages
  • 11.3 XSELECT Command Sequences
    • 11.3.1 Read Several Events Files Directly
    • 11.3.2 Screen and Extract GIS PH Mode Events Data
    • 11.3.3 Screen and Extract SIS BRIGHT or BRIGHT2 Mode Events Data
    • 11.3.4 Select Extraction Regions for Source and Background and Extract Spectrum
    • 11.3.5 Obtain GIS Response Matrices
    • 11.3.6 Obtain or Create SIS Response Matrices
    • 11.3.7 Generate the Ancillary Response File (ARF)
    • 11.3.8 Extract Events List to Use as a Light Curve for XRONOS
    • 11.3.9 Extract FITS Rate File to Use as a Light Curve for XRONOS
    • 11.3.10 Extract Soft and Hard Sky Images
  • 11.4 MKF Parameter Summary
    • 11.4.1 Time-Related Columns
    • 11.4.2 Attitude, Pointing, and Bit Rate
    • 11.4.3 SIS Status/ Monitors
    • 11.4.4 GIS Status/ Monitors
    • 11.4.5 Radiation Belt Monitor
  • 11.5 Important URLs
    • 11.5.1 ASCA Getting Started Guide
    • 11.5.2 ASCA GOF
    • 11.5.3 ASCA GOF: Processing and Data Analysis
    • 11.5.4 ASCA GOF: What's New
    • 11.5.5 ASCANews
    • 11.5.6 ASCA Observation Planning Guide
    • 11.5.7 ASCA Science Data Processing
    • 11.5.8 Background Normalization for Co-added Spectra
    • 11.5.9 Calibration Uncertainties
    • 11.5.10 FTOOLS
    • 11.5.11 GIS Background
    • 11.5.12 GIS3 CPU Trouble
    • 11.5.13 GIS Gain Correction
    • 11.5.14 GIS News
    • 11.5.15 SIS News
    • 11.5.16 XANADU
    • 11.5.17 XIMAGE User's Guide
    • 11.5.18 XRONOS User's Guide
    • 11.5.19 XSELECT User's Guide
    • 11.5.20 XSPEC User's Guide