Sarah Fisher
22 Sep 2021



Diagnostics software section leader

Sarah Fisher at her desk



Sarah joined ISIS 15 years ago after seeing a local advert in the run up to the construction of Target Station 2. “I came in as diagnostics support, installing and commissioning diagnostics for TS2 as well as keeping the TS1 diagnostics operational," she says.

The beam diagnostics constantly monitor the beam losses and intensity in the accelerators and the proton beams to ensure the beam is in the correct position in the beam pipe and that the beam's position on the targets is optimised. If an issue occurs that is operationally critical, where the beam loss is too high, or too much intensity is lost, the beam turns off automatically and the main control room is alerted. This is essential to prevent damage to components of the accelerator and to keep activation of the machine to a minimum so maintenance tasks can be undertaken during shutdowns.

There are also diagnostic monitors for other parameters of the beam such as profile and position within the beam pipe. These are generally used by the accelerator physicists to help diagnose problems with the beam and to investigate the behaviour of the beam during machine physics studies outside of user runs.

Much of the software needed to monitor these diagnostic data is written in the BASIC programming language, some of which is almost 30 years old. When Sarah arrived, she was given the task of developing the use of LabVIEW code for data acquisition, and this is now widely used.

There is still a lot of old software that needs updating. “We use the time when the accelerator is off to go through the BASIC scripts and re-write them." She adds, “The upcoming long shutdown will give us plenty of time to make and test improvements. We also want to increase the frequency of the data points we record: ideally we would record every pulse, but at the moment we sum and save the data once a day."

After getting more involved with LabVIEW, Sarah discovered there were a lot of people on site who were using the code. “I set up a LabVIEW user group in 2008, and people now join us from across STFC and the Harwell campus more widely. Our quarterly meetings give us a chance to see what other people are using it for, and to share best practice." Sarah is also on the committee for an international LabVIEW conference, which she uses as another opportunity to learn more about its possible applications. 

Contact: de Laune, Rosie (STFC,RAL,ISIS)