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Last modified: 8 February 2018


2nd Chandra/CIAO Workshop Hands-on Session

For the second Chandra/CIAO workshop, we have modified the format of the hands-on session. Each day will begin with instructional talks and the afternoon will be reserved for hands-on practice.

Practical Information:

  • There are 15 workstations called "DEMO1, DEMO2, ... DEMO15." With 30 people registered for the workshop, two people need to work at each computer.
  • Users should log-in as "cxcguest1", "cxcguest2", etc. on the corresponding machines. The passwords will be revealed on Monday.
  • All the "cxcguest" accounts are already setup to run CIAO2.1. On every window where you expect to run CIAO, you should simply type "ciao". For example:
    cxcguest-1: ciao
    CIAO configuration is complete... 
       version   :  CIAO 2.1 Wednesday, February 28, 2001
       bin dir   :  /soft/ciao/bin
  • Some useful checks:
    cxcguest-2: ciao -v
     This script sets the user's CIAO environment to utilize:
     version   :  CIAO 2.1 Wednesday, February 28, 2001
     bin dir   :  /soft/ciao/bin
     The current environment is already configured for:
     version   :  CIAO 2.1 Wednesday, February 28, 2001
     bin dir   :  /soft/ciao/bin
    cxcguest-3: echo $PFILES
    cxcguest-4: echo $CALDB
    cxcguest-5: echo $ATOMDB
  • The workspace is in
    15 subdirectories have been created called cxcguest1 through cxcguest15; please use the one relative to your machine.
  • Chandra data useful for the analysis can be found in
  • All the CIAO scripts are already downloaded in
    and can be called from the command line.
  • 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 2.1 Threads page.

  • Beginners:
    Introduction To the Data Model
    Introduction to Firstlook
    Introduction To Prism
    Data Filtering
    Getting Started With Sherpa
    Introducing Sherpa: ASCII Data & Errors and Single-Component Source Models
  • Imaging/Spectroscopy:
    Create True Color Image
    Extract ACIS Spectra and Make RMFs and ARFs
    Compute an Exposure Map
    Reprojecting Coordinates of a Solar System Object
  • Grating Analysis:
    Examining PHA2 Files
    Obtain Grating Spectra
    Compute Grating ARFs
    Extract Coadded and Grouped Nth-Order Source & Background Spectra and ARFs
    Fitting Grating Data
    GUIDE: Fitting and Identifying Spectral Lines
    Fitting Spectral Data: FITS Data & Responses and Multi-Component Source Models
  • Extended Source Analysis:
    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

Last modified: 8 February 2018
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