ERIS2026 Tutorials

Welcome to the European Radio Interferometry School (ERIS) 2026 where we hope that you learn how to go from telescope to science-ready images when using an interferometer. This website hosts the tutorials that you will do to get hands-on practice with data. This homepage will guide you in installing CASA, testing your installation and downloading the tutorial data.

If you have completed this already, head down to the bottom of the page where you can find the links to start the tutorial. Or go back to the main ERIS2026 school webpage.

Installing CASA

Linux

  • Most modern CASA installations require the libfuse2 library to be installed. Use your system's package manager to install this (e.g., on Ubuntu, run sudo apt install libfuse2).
  • Please use the following link to download the CASA version for your Linux distribution
  • Once downloaded, extract the package into an appropriate folder. E.g., you can use the tar command in the command line / terminal to do this: 
    tar xvf casa-6.7.5-18-py3.12.el8.tar.xz
  • This will make a folder named casa-6.7.5-18-py3.12.el8 in the directory you extracted in.
  • Open the command line and type in the following command:
    mkdir -p ~/.casa/data
    This will create a directory named data inside the hidden casa configuration directory in your home folder.
  • You can run CASA by running casa-6.7.5-18-py3.12.el8/bin/casa in your command line.
  • An easier way is to set a bash alias so that you can run CASA by just typing casa into the command line (from anywhere!). This can be done using the following code (where you want to replace (path_to_CASA_folder) with the CASA folder path (you can find your current path with the command pwd). Note that this command will modify your .bashrc file in your home directory by adding a line at the end of the file: 
    echo 'alias casa=(path_to_CASA_folder)/casa-6.7.5-18-py3.12.el8/bin/casa' >> ~/.bashrc
    For example, if I untarred CASA in my home folder, this command would be 
    echo 'alias casa=/home/radcliff/ccasa-6.7.5-18-py3.12.el8/bin/casa' >> ~/.bashrc
  • Test that this alias works by opening a new terminal or by typing source ~/.bashrc, then typing casa in it. This should open up CASA and the logger window.

Mac OS

  • Please use the following link to download the correct CASA version for your Mac OS version.
  • Open the Terminal and type in the following command:
    mkdir -p ~/.casa/data
    This will create a directory named data inside the hidden casa configuration directory in your home folder.
  • You should have already downloaded a disk image file (.dmg) file that should be similarly named as casa-6.7.5.31-XX.0-py312.dmg where the XX corresponds to your Mac OS version.
  • Open the Finder and double click on the file to get it to mount. This opens another Finder window where there will be CASA and a README.md file.
  • Open another Finder window and open the Applications folder. Copy CASA (or drag and drop) into the Applications folder
  • Within the applications folder, right click and open CASA so that we can override the Apple security safeguard. If this doesn't allow you to open first time, try again. This should finish with a Terminal window opening and the CASA prompt present.
  • Within the CASA prompt type: !create-symlinks and follow the prompts.
  • Leave the CASA window open, and go to System Settings → Privacy & Security → Full Disk Access and make CASA, and the Terminal apps have full disk access.
  • Once complete, close CASA and the Terminal app completely (i.e. right-click on the Mac dock to quit). Open a new Terminal tab/window and type in casa. This should open up CASA and the logger window.

If these steps have run with no errors, please follow the instructions below to test your CASA installation.

Installing CARTA

We also need to install the CARTA tool which will be used to visualise images. Follow the instructions on the following webpage to install it https://cartavis.org/#download. You will want to install the stand-alone application.

Downloading the data

Before continuing, you should download all the following tar bundles using the links below. Ensure that your drive has at least 10GB of space free. If you have already tested your CASA installation, you may already have the ERIS26_calibration_tutorial.tar.gz file.

Alternatively, you can use enter the following in the command line to download these data,

wget https://www.jb.man.ac.uk/ERIS26/data/ERIS26_calibration_tutorial.tar.gz
wget https://www.jb.man.ac.uk/ERIS26/data/ERIS26_imaging_tutorial.tar.gz
wget https://www.jb.man.ac.uk/ERIS26/data/ERIS26_adv_imaging_tutorial.tar.gz

Testing your CASA installation

With CASA installed, you want to follow the next set of instructions on the following webpage to check that your installation is working correctly

Starting the tutorials

Below you can find the various links to the tutorials we are going to do during ERIS2026. Please ensure you have completed the tests of your CASA installation before starting here. Your tutors will instruct you on which tutorial you should be completing. Note that not all tutorials are hosted here but you will get instructions on how to proceed from your tutors.