Defining the SLIMOS role: feedback from training and real shifts

Giuseppe Mornacchi tells ATLAS e-news about the SLIMOS role to ensure safety during running.

4 February 2008

Over the Christmas period, from the 22nd December until the 6th of January, about 15 ATLAS physicists participated in the first full-training exercise for SLIMOS, which stands for ‘Shift Leader In Matter Of Safety’. The role of the SLIMOS will be important to maintain the experimental installation operational and to keep high safety standards down in the pit. When ATLAS point 1 will be operating normally, the SLIMO shifter will be responsible for making sure that all services are working correctly both when data taking will be ongoing and during shutdowns.

Christmas was quieter than usual down in the pit, but still, point 1 remained operational –with all the services and facilities running full speed. Each of the physicists trained as SLIMOS did a full day shift. In every shift, the SLIMOS went down into the cavern twice and did a pre-defined tour in order to certify that there were no problems.

The SLIMOS desk in the control room has most of the tools and documentation to become operational; now we will have to decide when to start staffing the control room with a 24/7 SLIMOS shift.

“It was the first time we did the SLIMOS training on that scale and it was a great success,” says Giuseppe.

During the exercise, there were a few minor failures of the cooling system. In all cases, the SLIMOS person in charge did whatever was necessary to re-start the service that failed and successfully resolved the problems encountered.

Maintenance works

As every year, the ATLAS detector cooling and cryogenic systems are undergoing extensive yearly checks. From the 7th to the 22nd of January, the CERN cooling and ventilation group performed maintenance work at point 1 cooling system. The cryogenics system maintenance work also started on the 7th and finished on the 28th of January.

On the 22nd of January, more than 100 electrical emergency stop buttons that allow total and partial power cuts in point 1, underwent a full test that was very succesfull.

The maintenance works went according to schedule, and now P1 is back into full operation mode.


Cristina Jimenez