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Last modified: 8 February 2018


3rd Chandra/CIAO Workshop Hands-on Session

Practical Information:

  • There are 15 workstations available -- DEMO1, DEMO2, ... DEMO15. With 19 people registered for the workshop, some people will need to work in pairs.
  • Users should log-in as cxcguestx, where x is the machine you are on; i.e. the user on DEMO1 is cxcguest1 ... DEMO15 is cxcguest15. The passwords will be revealed Monday afternoon.
  • All the accounts are already setup to run CIAO2.2. On every window where you expect to run CIAO, you should simply type "ciao". For example:
    unix% ciao
    Warning: Not fully tested version of Solaris
    CIAO configuration is complete... 
     CIAO version     :  CIAO 2.2 Saturday, October 13, 2001
     Proposal Toolkit version :  NRA 4.0 Saturday, October 13, 2001
     bin dir          :  /soft/ciao/bin
    The warning is issued because CIAO 2.2 has not been fully tested in Solaris v2.8, which this machine is running.
  • Some useful checks:
    unix% ciao -v
     The current environment is already configured for:
     CIAO version     :  CIAO 2.2 Saturday, October 13, 2001
     Proposal Toolkit version :  NRA 4.0 Saturday, October 13, 2001
     bin dir          :  /soft/ciao/bin
    unix% echo $PFILES
    unix% echo $CALDB
  • The workspace is in /data/ciao_demo/. 15 subdirectories have been created called cxcguest1 through cxcguest15; please work in the one relative to your machine. A link to this location has been set up in the home directory of each account:
    unix% pwd
    unix% cd workshop/
    unix% pwd
  • Chandra data used in the analysis threads can be found in /data/ciao_demo/threads. A link to this location has been set up from the workspace:
    unix% pwd
    unix% ls -l
    total 0
    lrwxrwxrwx   1 cxcguest1      11 Nov  2 14:21 data -> ../threads/
    unix% ls data/
    ChIPS           acis-i          acisletg        hrciletg
    GUIDE           acis-s          hrc-i           hrcsletg
    Sherpa          acishetg        hrc-s
    The CIAO tools accept paths as part of the input file names, so it is not necessary to copy all the data to your working directory. You may also set up symbolic links to access the data.
  • Beginning with CIAO 2.2, the scripts are included in the baseline software distribution. This means that they can be called from the command line in the same manner as the CIAO tools:
    unix% which ciaover
    unix% ciaover
    CIAO version: CIAO 2.2
    CIAO series: CIAO2
    Current directory is writeable
    DM tools found in /soft/ciao/bin
    DM library found in /soft/ciao/lib
    Any script that has not yet been added to this directory may be downloaded from

Suggested Analysis Sessions:

All the threads listed below can be found from the CIAO 2.2 Threads page.

  • Beginners:
    Introduction to the Data Model
    Introduction to Firstlook
    Introduction to Prism
    Data Filtering
    Create True Color Image
    Extract ACIS Spectra and Make RMFs and ARFs
    Getting Started With Sherpa
    Introducing Sherpa: ASCII Data & Errors and Single-Component Source Models
    Fitting Spectral Data: FITS Data & Responses and Multi-Component Source Models
  • Grating Analysis:
    Examining PHA2 Files
    Obtain Grating Spectra
    Compute Grating ARFs
    Create Grating RMFs
    Extract Coadded and Grouped Nth-Order Source & Background Spectra and ARFs
    Fitting Grating Data
    GUIDE: Fitting and Identifying Spectral Lines
    Extended Source Analysis:
  • Extended Source Analysis:
    Weighting ARFs and RMFs
    Create an Image of Diffuse Emission
    Create True Color Image
    Obtain and Fit a Radial Profile
    Compute an Exposure Map
    Create a PSF
  • Source Detection:
    Compute an Exposure Map
    Detecting Sources in Imaging Observations
    Estimating Source Counts in Imaging Observations
    Obtain and Fit a Radial Profile

Last modified: 8 February 2018
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