ERIS2022 Tutorials

Welcome to the European Radio Interferometry School (ERIS) 2022 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. Finally, should you wish to go back to the main ERIS2022 webpage, use the link below

Installing CASA

To begin, download the appropriate CASA version for your operating system from https://casa.nrao.edu/casa_obtaining.shtml. Ideally you want to select python3.8 version but python3.6 is ok unless you wish to do the VLBI advanced tutorial. Once downloaded, follow the instructions below that are appropriate for your operating system

Linux

  • 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-6.5.1-23-py3.8.tar.xz
  • This will make a folder named casa-6.5.1-23-py3.8 in the directory you extracted in.
  • You can run CASA by running casa-6.5.1-23-py3.8/bin/casain 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 - can find that out with the command pwd): 
    echo 'alias casa=(path_to_CASA_folder)/casa-6.5.1-23-py3.8/bin/casa' >> ~/.bashrc
    For example, if I untarred CASA in my home folder, this command would be 
    echo 'alias casa=/home/radcliff/casa-6.5.1-23-py3.8/bin/casa' >> ~/.bashrc
  • Test that this alias works by opening a new command line and type casa into it. This should open up CASA and the logger window.

Mac OS

  • For the Mac OS installation, you should have downloaded a disk image file (.dmg) file that should be similarly named as casa-6.5.1.23-11.0-py38.dmg
  • 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 safguard. If this doesn't allow you to open first time, try again. This should end with a Terminal window opening and the CASA prompt present.
  • Within the CASA prompt type !create-symlinks and then !update-data.
  • Once complete, open a new Terminal and type in casa. This should open up CASA and the logger window

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.

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

wget https://www.jb.man.ac.uk/DARA/ERIS22/data/ERIS22_calibration_tutorial.tar.gz
wget https://www.jb.man.ac.uk/DARA/ERIS22/data/ERIS22_imaging_tutorial.tar.gz
wget https://www.jb.man.ac.uk/DARA/ERIS22/data/ERIS22_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 ERIS22. 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.

If you wish to do the tutorial in its entireity, follow the link below:

The advanced tutorial on polarisation is also hosted here. Please follow the link below to download the data and complete the tutorial.