Present: Verena Kain, Brennan Goddard, Roger Bailey, Mike Lamont (chair), Jan Uythoven, Helmut Burkhardt, Alex Koschik, Ralph Assmann, Massimo Giavannozzi, Magali Gruwe, Frank Zimmermann.
Sector test is a standard procedure for all large accelerators. Performed thoroughly it has the potential to reveal potentially major problem (see LEP, RHIC etc). If we don't do it for the LHC we will be the first to skip it. If things are OK, so well and good, if there are problems the test gives us appreciable lead time. In this sense the test clearly allows for RISK minimisation.
| System | Integration issues |
| Power converters | |
| Magnetic Field Model | transfer functions, harmonics, cycling etc. |
| Injection Kickers | pre-pulses, diagnostics, interlocks |
| Septa | diagnostics, interlocks |
| TDI | controls, interlocks |
| Collimators | control, diagnostics |
| Instrumentation: Screens, BCT | |
| Instrumentation: BPMs | concentration, timing, RT |
| Instrumentation: BLMs | interlocks, critical settings |
| RF low level | synchronisation, pre-pulses, fast timing |
| BST | |
| Timing | |
| Controls infrastructure | Networks, front-ends, timing, FIP, software etc. |
| Beam Interlock System | Kickers, safe beam parameters |
| Software Interlock system | |
| Access system | LHC Access project is highly motivated by the sector test to debug its numerous sub-systems and test all the operational procedures such as the patrol. |
| Radiation monitoring | |
| Radiation protection |
Note experience in this area, TT40: wrong vacuum chamber, corrector polarity errors, BPM polarity errors, screen polarity errors
Tool debugging - it will be required.
Subsidiary systems ready on time
Is there time enough left to chagne anything? Yes. There had better be. Examples: vacuum, interlocks
Time foreseen in commissioning plan for injection and first turn of ring 2: 4 days - optimistic if none of the problems forthcoming in the sector test have been resolved. Time spent during the sector test will be directly recuperated.
Excluding the lower priority measurements, 8 days of measurements are foreseen. For proper understanding of the LHC and safe, effective commissioning, these measurements will have to be done during the commissioning phase. Time spent during the sector test will be directly recuperated.
- Commission TI 8 end, injection and thread to IR7
- Commission trajectory acquisition and correction
- Polarity checks
- Commission Beam Loss Monitor system
- Optics measurements
- Aperture checks
- Effect of magnetic cycle
- Field quality checks
- Quench limits and BLM response
- Setting up of injection machine protection
Pre-test commissioning of all systems listed above plus subsequent problem resolution, analysis, improvements...
Commissioning of all systems together plus subsequent problem resolution, analysis, improvements...
Less to do in the narrow window for operation machine checkout following the end of hardware commissioning.
Two points here:
In fact, on reflection, the time spent on the sector test is, give or take some minor planning adjustments, recoverable.
Major problem resolution - lead time - risk reduction has to be major motivation for the test. If there are any serious problems, the sooner we discover them, the more time we have to attempt to resolve them.
Less serious beam related problems tend to arrive serially, and are solved one at a time. If during full commissioning and under pressure, the quick fix will always be adapted. 6 months lead time gives the opportunity to deal with a lot of issues properly.
WILL THE SECTOR TEST DELAY THE START OF LHC COMMISSIONING WITH BEAM?
Properly planned should have no significant impact on installation schedule. There is a significant gain if there is a problem.
The test in 2007 can be performed largely in the shadow of ongoing installation and commissioning. The shift to 2007 reduces considerably the potential impact on: transport, installation, LHCb.
2006: Small number of collimators/scrapers/absorbers have and D4 to be left
out to leave room for temporary dump installation. .Re-visiting zone for
finishing installation is not ideal.
2007: Install D3/D4 – two options:
Either way there will be less impact in 2007. Collimator option reduces
significantly the impact on installation in IR7.
Depending on timing of test, impact on 6-7 could be eliminated if interconnection
work has finished. It would be convenient to close sector 6-7 immediately
to the right of IP6 eliminating the need for a temporary gate in the
tunnel.
Should be less impact. Installation in 6-7 and 8-1 should have been fully completed. Transport through the zones not required.
Test remains an important milestone - could close tunnel at IP6 negating the need for temporary installation of gate in 6-7.
There should be no need for magnet transport through the affected sectors - to be confirmed.
Interconnection work in 6-7 should have finished.
Sectors 7-8 and part of 8-1 will need to be kept cool, or cooled for the test.
Some Hardware commissioning support will be required to ensure proper functioning of the QPS, PIC etc. However, this as pre-cursor to the real thing should be handled for the most part by operations from the CCC.
Cryogenics support will be required to ensure proper functioning of the cryogenics system.
Rolf Linder..
"There was always part of the installation (VELO related) planned after the
sector test; that is why we preferred to have this test in December
2006, which would leave us sufficient time for this. However, with the delay
in delivery of the last beam pipe section, not having the sector
test in 2006 will relieve the strong pressure completing the beam pipe before
November this year"
Depending on the definition of spring 2007, we have to see what implications a sector test in spring 2007 and the revised general LHC schedule will have on the LHCb installation and commissioning.
Potential for ess worries about zonage and material activation.
Under time pressure can shorten time - essential test only - already prioritised. Work to minimise foot-print.
ML 22/11/05