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Last modified: 8 February 2018


1st Chandra/CIAO Workshop Hands-on Session

Practical Information:

  • There are 12 workstations called "DEMO1, DEMO2, ... DEMO12" and two people should work at each workstation.
  • Users should log-in as "cxcguest1", "cxcguest2", etc. on the corresponding machines (passwords will be revealed on Tuesday).
  • All the "cxcguest" accounts are already setup to run CIAO2.0.2. On every window where you expect to run CIAO, you should simply type "ciao". For example:
    cxcguest-1: ciao
    Setting up to use release version of CIAO, from /soft/ciao
    I will automatically update the following files in your $HOME dir:
    if they are older than the files in the distribution, however backup
    copies will be saved with a .bak extension.
    CIAO configuration complete!
  • Some useful checks:
    cxcguest-2: ciao -v
    Your CIAO version is: 2.0.2
    Your CXC_PROP_CLI version is: 3.0
    cxcguest-3: echo $PDIRS
    cxcguest-4: echo $CALDB
    cxcguest-5: echo $ATOMDB
  • The workspace is in
    12 subdirectories have been created called cxcguest1 through cxcguest12; please use the one relative to your machine.
  • Chandra data useful for the analysis can be found in
  • All the CIAO scripts can be found in the directory
  • If you need to access CALDB files, they are in
    /soft/ciao/CALDB, which is linked to /data/CALDB/
  • If you need to access ATOMDB files, they are in
    /soft/ciao/ATOMDB, which is linked to /data/axaf8/atomdb/

Suggested Analysis Sessions:

All the threads listed below can be found from the CIAO 2.0 threads page.
  • Beginners:
    Introduction To the Data Model
    Introduction To Using Prism
    Data Filtering
    Create True Color Image
    Extract an ACIS spectrum and make RMF and ARF
    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
    Create Grating ARFs
    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:
    Create True Color Image
    Obtain a Radial Profile
    Exposure Map
  • Source Detection:
    Exposure Maps
    Source Detection
    Estimate the Number of Counts in a Source

Last modified: 8 February 2018
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