Managing Data from the Astra Gemini and Vulcan Lasers
01 Jun 2017



Each time the Central Laser Facility (CLF) fires one of its lasers it generates data which needs to be stored ready for analysis of laser shot trends and behaviour, energy delivered, any variations in the laser beam and a variety of other information.

Kevin Phipps and Frazer Barnes view ICAT data for STFC's Vulcan Laser

Kevin Phipps (left) and Frazer Barnes view ICAT data for STFC's Vulcan Laser

Credit: STFC

For nearly 10 years the Scientific Computing Department's (SCD) Reseach Data Group has been working with staff supporting CLF's Astra Gemini laser to catalogue all of this laser diagnostic data, which comes from sensors, cameras and other equipment such as oscilloscopes. For the last 5 years or so the data has been stored in ICAT, a metadata catalogue developed and maintained by colleagues in the Research Data Group (RDG) specifically to support Large Facility experimental data.  ICAT is also in use at ISIS, Diamond, ESRF and the Spallation Neutron Source at Oak Ridge, Tennessee.

“We make the raw data available to laser operators and users who are doing experiments via a web-based application known as eCAT, which we developed specifically for this purpose," says Kevin Phipps, CLF Service Manager for SCD.  “Operators use this data to confirm that the laser is set up and operating correctly."

The ICAT system for Astra Gemini has proved useful primarily for allowing Operators to easily get data for each shot and combine it with other data sources to give an overview of the state of the entire beam line. Over the last year the RDG has been collaborating with CLF staff who are supporting the Vulcan laser, to adapt the system for their use too.

Kevin explains, "This involved CLF making changes to the way they save diagnostic data, mainly in the area of the file names and formats, such that the ingestion tool run by RDG can read the data and catalogue it correctly in ICAT. The users can now access the Vulcan laser data using eCAT."

Over the past year the CLF has also bought in a tool named DARB - an automated system for Diagnostics, Analysis, Review and Backup - developed at Strathclyde University for automatically saving data from additional diagnostics such as specialist, scientific cameras that the users set up during their experiments. This has been adapted to save the data in the format required for ingestion into ICAT, and was successfully tested for the first time on a Vulcan experiment in March 2016. The plans for the coming year are to put the Vulcan ICAT system into full production and to deploy the DARB software fully for both Vulcan and Astra Gemini.

“From the long term collaboration between CLF and SCD for the Astra Gemini laser, it is gratifying to see that the system has become increasingly valued by CLF and continues to evolve to meet their requirements," says Kevin. “Being able to take a system that has had years of development effort invested in it and, for a relatively small amount of effort, adapt it for use by another laser has been cost effective as well as allowing a complex system to be put in place within a relatively short period of time.

“With the two lasers now using common data management software, it also means that future updates to the software potentially benefit both lasers. The addition of the DARB tool has proved to be a successful collaboration with Strathclyde University, and again, with a relatively small amount of effort, it has been possible to customise it so that it integrates with the ICAT tools."

Contact: O'Sullivan, Marion (STFC,RAL,SC)