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Last modified: 4 June 2024


Installing CIAO 4.16 and CALDB 4.11.2 with the ciao-install script.

Users can also install CIAO using conda package manager commands. Visit the download page for help choosing which installation method to use.

  1. Please be aware of the following issues before installing CIAO 4.16 (see the watchout page for more information):

  2. Download the ciao-install installation script.

    [New]By default this will download and install CIAO and Sherpa with Python 3.11 along with the base CALDB calibrations files. Go to the Custom CIAO/CALDB install page for information about how to add or remove additional packages including the blank sky background CALDB files and the CIAO source code.

    You need to download a separate version of the ciao-install script for each version of CIAO.

    What is the download called?

    The following document assumes that the script has been downloaded with the name ciao-install. This is the default name, but the web browser may well add on a suffix (such as "(1)") to avoid overwriting an existing file. Please rename the downloaded file - or use the new name - in the following steps!

  3. [WARNING]
    Do Not Install as Root or Super User

    It is strongly suggested that CIAO be installed as a non-privileged, regular user and not as the root or a super user.

    Install CIAO in new terminal window

    Users should install CIAO in a new terminal window which is not already configured for CIAO-4.16 or earlier, nor setup for any other common analysis packages such as FTOOLS/HEASOFT/XSPEC, SAS, or others.

    Run the script that has been downloaded; this will download the requested parts of CIAO and install them on your system, and is described in more detail in the Installing CIAO 4.16 using the ciao-install script thread:

    unix% bash /<path>/ciao-install
    CALDB blank sky background files

    By default, ciao-install installs the Chandra Calibration Database (CALDB) with neither the ACIS nor HRC blank sky background files. To include them include --add acis and/or --add hrc in the command. For example to install both use:

    unix% bash /<path>/ciao-install --add acis --add hrc

    We strongly suggest that the smoke tests are run, the results reviewed, and that the bug page for CIAO installation is reviewed before contacting the CXC Helpdesk if there are any problems.

  4. Set up an alias to start CIAO: for example, if CIAO has been installed into the directory /soft/ciao-4.16/, then

    alias ciao "source /soft/ciao-4.16/bin/ciao.csh"

    for csh and tcsh users and

    alias ciao="source /soft/ciao-4.16/bin/"

    for bash and zsh users.

    Users may wish to add this alias command to their start-up scripts. For bash and zsh the alias can be added to the $HOME/.bash_profile or $HOME/.bashrc file. For tcsh the alias can be added to the $HOME/.tcshrc or $HOME/.cshrc file.

    The start-up scripts are automatically sourced when the user opens a new terminal window. To use the newly created alias in existing, open terminal windows users need to source the start-up script.

  5. This alias should then be called in the terminal in which you plan to use CIAO (multiple terminals can be set up to use CIAO at the same time). When called, a version message will be displayed:

    unix% ciao
    CIAO 4.16.0 Tuesday, December 05, 2023
      bindir      : /soft/ciao-4.16/bin
      CALDB       : 4.11.2

    Please review the notes on starting and installing CIAO for potential conflicts between CIAO and other systems, such as XMM SAS and HEASoft.

    The ciaover script can be used to display the CIAO and CALDB versions (it reports the same information that the ciao alias above does, and extra information is displayed when called with the -v flag). The --version flag to python can be used to display the Python version in use:

    unix% python --version
    Python 3.11.6
  6. Once CIAO has been started, the MARX suite of tools for simulating the on-orbit performance of Chandra can be downloaded and installed with the install_marx script (it can be installed at any time). The script takes a single argument, the location to install MARX. Change /soft/marx to a suitable location:

    unix% install_marx /soft/marx

    An alias can be created to set the MARX environment. For instance

    alias setup_marx "source /soft/marx/marx-5.5.3/setup_marx.csh"

    for csh and tcsh users and

    alias setup_marx="source /soft/marx/marx-5.5.3/"

    for bash and zsh users.

  7. Finished! CIAO is now installed and you can begin your data reduction and analysis work.

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