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Last modified: 13 December 2018


Downloading CIAO 4.7

The ciao-install script is designed to simplify and automate the installation and upgrade of CIAO and the Chandra Calibration DataBase (CALDB). ciao-install FTPs the selected files to your computer, verifies them via md5sum, and unpacks them. The script configures CIAO, sets up the command-line ahelp system, and (optionally) runs the CIAO smoke tests.

The ciao-install.README file has detailed information on the script. For a summary of options, run the script with the "-help" option.

Known issues are listed on the Installation & Smoke Tests bug page.

OS X 10.11: El Capitan

[New] (1 Oct 2015) CIAO 4.7 does not work with Apple's OS X 10.11: El Capitan. While some individual tools and applications may work, many of the Python and Shell based applications and contributed scripts do not.

OSX: XQuartz 2.7.8 (released 2015-10-17)

[New] (20 Oct 2015) ChIPS in CIAO 4.7 is incompatible with XQuartz 2.7.8. Users must use version 2.7.7 or earlier.

End of Support: 32bit Linux and OSX 10.6.8/10.7

CIAO 4.7 will be the last CIAO release that will be available for 32bit Linux and OSX 10.6.8/10.7.

Users are encouraged plan ahead for 2015 if still using any of these operating systems.

Quick Installation

This method allows ciao-install to determine what platform you are using, then downloads and installs the standard CIAO installation: CIAO tools, ChIPS, Sherpa, the main CALDB tarfile, and the science scripts.

This method may also be used to download and install software patches, calibration releases, and science script updates.

  1. Check the supported platforms page for the machine you are running on.

  2. Run the script:

    unix% bash /<path>/ciao-install
  3. Check for smoke test results for errors. Known issues are listed on the Installation & Smoke Tests bug page.

CIAO and the full CALDB (excluding background files) require 3 GB of disk space to download the tarfiles and 9.05 GB to install the software and calibration files. Upgrading an existing CALDB requires about 70% less disk space for the tarfile.

For detailed instructions, refer to the ciao-install thread page.

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Custom Installation

Select the CIAO and CALDB packages you need, then download the custom ciao-install script to install them.

Step 1: Choose a Platform

The default setting - "Autodetect Platform" - allows ciao-install to determine what platform you are using and to select the appropriate build of CIAO.

The Platform Support page has more information on the officially supported CIAO platforms.

Step 2: Customize your Software Installation

Standard CIAO installation
  • Selects a complete binary installation of CIAO tools, ChIPS and Sherpa, the main CALDB tarfile, and the science scripts.
Binary Packages
  • CIAO analysis tools - v1
  • Sherpa modeling and fitting package - v1
  • Chips plotting package - v1
  • Prism file-browsing GUI - v1
  • ObsVis observation visualizer for proposal planning - v1
Calibration Database (CALDB)

The CALDB contains all the calibration files required for Chandra data analysis.

If CALDB has not been installed, ciao-install downloads and installs the full tarfile. If ciao-install determines that CALDB 4.7.3 or higher is already available, it downloads the patch file and upgrades CALDB to the most recent version.

  • CALDB v4.8.2
  • ACIS background event files v4.7.6
  • HRC background event files v4.7.7
Science Scripts Package

The scripts package contains analysis scripts and modules that extend the functionality of CIAO.

  • Scripts Package - version 4
Source Build

The source build option is for users who wish to compile CIAO themselves.

There are platform specific build instructions for Linux and OSX when starting with the CIAO precompilied OTS packages. Some common build problems are discussed on the bug page for known source build issues. Users must either also select the appropriate binary packages or must rebuild all the Off The Shelf (OTS) packages as outlined in the instructions.

  • Full source build
  • Source files for the selected binary packages

Step 3: Download the Installation Script

If a version of ciao-install exists in your download directory, some browsers will save the new script with a number in filename, e.g. "ciao-install(2)". Be sure you are running the newest download of your script.

Run the script:

unix% bash /<path>/ciao-install

For detailed instructions, refer to the ciao-install thread page. Known issues are listed on the Installation & Smoke Tests bug page.

Step 4: Check smoke test results

Users are strongly encouraged to run the CIAO smoke tests. They only take a few minutes to run and will immediately highlight any system incompatibilities before you get too deep into your analysis.

There are some known failures and workarounds for certain platforms. as listed on the Installation & Smoke Tests bug page.

If you are still having problems after reviewing those pages, please contact CXC Helpdesk

Manual Installation

If you are having problems using the ciao-install script, refer to the Manually Installing CIAO 4.7 thread. It explains how to retrieve the files with wget and then install CIAO step-by-step.

Last modified: 13 December 2018
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