Chamonix 2011 LHC Performance Workshop

Session

Session 01 Review of 2010 Operations

Session01

24 Jan 2011, 08:30

Chamonix

Conveners

Session 01 Review of 2010 Operations

• Malika Meddahi (Chair)
• Laurette Ponce (Scientific Secretary)

Presentation materials

paper

Summay_Discussion_Session1.ps

7. LHC Operation – as viewed from the Experiments

Massimiliano Ferro-Luzzi (CERN)

24/01/2011, 08:30

This talk will try to summarize how the LHC experiments have perceived the 2010 run. A critical review of LHC operation, beam conditions and luminosity delivery will be given, as well as proposals for improvements.

8. Operational challenges (Feed forward from Evian LHC operation workshop)

Mike Lamont (CERN)

24/01/2011, 09:00

An attempt is made to synthesize the outcomes of the Evian workshop. A list of issues and prioritized actions will be presented. Among others the following issues will discussed: overall operational efficiency and potential improvements; possible optimization of the operational cycle; machine configuration and associated commissioning requirements; adequacy of LHC operational procedures and tools.

9. Injection – issues and potential solutions

Verena Kain (CERN)

24/01/2011, 09:30

Due to the sensitivity of the LHC beam loss monitor systems combined with low thresholds, losses at injection became a limiting factor during the filling of the LHC. All parameters, longitudinal and transverse had to be well controlled not to trigger the beam dump at injection. The cause of these losses will be summarized and typical loss patterns and other diagnostics described. Mitigation...

10. Vacuum and Cryogenics observations for different bunch spacing

Dr Jose Miguel Jimenez (CERN)

24/01/2011, 10:20

Following the observations of high pressure rises induced by an electron cloud building up in the LHC beam pipes, studies were launched with beams with 50 and 75 ns bunch spacing at injection energy and with a ramp to 3.5 TeV (only 50 ns bunch spacing). This talk will summarize the observations made on the beam vacuum and cryogenic systems for both 50 and 75 ns bunch spacing and with a ramp...

11. Beam observations with different bunch spacing and overall synthesis

Gianluigi Arduini (CERN)

24/01/2011, 10:45

Machine studies have been performed at the end of the 2010 proton run to study the machine performance with bunch trains with 50 and 75 ns spacing in preparation for the proton run in 2011. The results of the observations and measurements will be summarized and compared with existing models. Possible running scenarios for 2011 will be outlined.

20. How can we reduce the "no beam" time?

Dr Walter Venturini Delsolaro

24/01/2011, 11:10

The machine operational efficiency will be analyzed by looking at the downtime statistics over the 2010 run. Hardware reliability will be reviewed and possible improvements considered. Access management, access recovery, duration and frequency of scheduled technical stops will also be discussed. Finally, the overhead of switching to ions and back will be briefly addressed.

12. Optimisation of the nominal cycle

Dr Stefano Redaelli (CERN)

24/01/2011, 11:40

The energy ramp and the betatron squeeze are critical phases of the LHC operation. During the squeeze, delicate optics manipulations take place when the stored energy is maximum. Ramp and squeeze were commissioned rapidly and smoothly became operational. On the other hand, for the first commissioning exercise, the focus was put on machine safety and on operational robustness rather then in...

60. Discussion

24/01/2011, 12:00