Week 29 - Injector Long MD 

(From Monday 19/07 at 20:00 to Friday 23/07 at 08:00 in dedicated and from Friday 23/07 08:00 to Saturday 24/07 08:00 in // to LHC)

Prior to this MD block there is a 12 hours Technical Stop in the CPS complex, and 36 hours stop for the SPS. The Technical Stop starts on Monday 19/07 at 08:00 for all the machines.

- Monday 20:00 - Tuesday 08:00 => PS B field fluctuation studies in dedicated. During this time the SPS remains in Technical Stop to allow for pumping after the exchange of the liners/dipoles. Supercycle: 8 bp

Contact people: G. Métral, OP

- Tuesday 08:00 - Tuesday 17:00  =>  Check of the LHC25 ultimate intensity in the PSB/PS

Contact people: G. Rumolo, H. Damerau, S. Hancock

- Wednesday 04:00 - Wednesday 08:00  => Supercycle change to MD_26_120_18000_2009_V1.csv  (coastable at 120 GeV/c, 15 bp, some references can be found at https://ab-mgt-md-users.web.cern.ch/ab-mgt-md-users/2009/MDCycles/SomeReferencesForpCoastAt120GeV/Ref.htm). Set up of the supercycle (first with 1 bunch per injection, and then with 4 bunches per injection)

- PSB user = LHCINDIV

- PS user = LHCINDIV

- SPS user = LHCMD1

- RF MMI target = LHCMONO

For the coast, mask the following SIS interlocks: KICKERS_SPSRING (essentially for the MKD_EARLY_ENABLED), switch off the MDSH119 (otherwise it will trip), POWER_CONVERTERS_TT10 (as some could trip during the coast) and BLRING_DUMP_CHANNEL_VETO.

Contact people: BE/OP, BE/RF

- Wednesday 08:00 - Wednesday 16:00  => Collimation studies with the new BPM integrated LHC prototype collimator (check availability of BI people)

Contact person: R. Assmann

- Wednesday 16:00 - Wednesday 17:00  =>  Supercycle change and set up: SPS takes beam on the LHC_4Inj_FB10860_FT835_2010_V1.csv supercycle, 18bp, (some references can be found at https://ab-mgt-md-users.web.cern.ch/ab-mgt-md-users/2009/MDCycles/SomeReferencesForLHCNominalCycle/Ref.htm).

Contact people: BE/OP, BE/RF

Pre-requisites to start the LHC25 MD (following on the list):

- The interlock threshold on the temperature of the MKE kickers should be ~ 90º C (it should be ~ 70º C when there are extractions) => No need to call Etienne Carlier anymore as it is done in SIS.

- With LHC beam the ZS should be RETRACTED / HV to 20 kV / ION TRAPS ON (the ZS expert must be informed). At the end of the MD Ht conditioning should be foreseen before applying back the HV to its nominal value.

- The cooling circuit for the septa magnets (circuits 214, 414 and 614) should be switched OFF (by TI from the CCC).

- Block the fast vacuum valves OUT in the injection and extraction areas (LSS1, LSS2, LSS4 and LSS6) => Tony Mongelluzzo (TE/VSC, 165116) takes care of this (also after the MD to come back to the initial situation), it takes ~20 minutes. The list of the 11 valves VVFA and VVFB to be blocked during the MD are:

BA 1 : VVFA 11901

BA 2 : VVFA 21701, VVFB 21877, VVFB 21802

BA 4 : VVFA 41638

BA 6 / TT 60 : VVFA 610213, VVFA 61957, VVFA 61637, VVFA 61460, VVFB 61802, VVFB 61877

- Disconnect the MOPOS (at least the three sextants without the attenuators). Contact Thibaut Lefevre.(BE/BI, 165041)

- The magnets with the e-cloud monitors are 4 dipoles: MDHW51832, 51836, 51838, 51853, all with 0.12 T (MDHW51832 with 25 A). In addition, there is a C-magnet (MDPH51753 with 28.5 A, in series with 754 to compensate) which contains a sample which can be inserted and removed.

- Wednesday 17:00 - Thursday 00:00  =>  Electron cloud studies with the LHC25 beam increasing the current in small steps from nominal to ultimate (4 batches, vacuum and temperature interlocks permitting). This includes ECM measurements on half coated liner to see whether a deterioration will occur during the run (this liner will then remain installed to monitor the aging of the channels with carbon), pressure measurements on the separate vacuum system to verify effects of the beam which are not related to pressure and instability detection studies.

Contact people: SPS Upgrade Study Team (M. Taborelli, E. Metral, G. Rumolo, W. Höfle, V. Mertens)

- Wednesday 00:00 - Thursday 07:00  => Multi-bunch resistive wall instability studies in the SPS

Contact person: E. Métral, N. Mounet, W. Höfle

- Thursday 07:00 - Thursday 08:00  => Supercycle change to MD_26_120_L18000_2009_V1.csv  (coastable at 120 GeV/c, 15 bp)

Contact people: BE/OP, BE/RF

- Thursday 08:00 - Friday 08:00  => UA9

Contact person: W. Scandale

- Friday 08:00 - Friday 09:00  => Supercycle change to one including the  LHC_4Inj_FB7260_FT_835_2010_V1.csv  cycle (for LHC50, 15bp). Set up

Contact people: BE/OP, BE/RF

- Friday 09:00 - Friday 18:00 in // to LHC  =>  Electron cloud studies with the LHC50 beam increasing the current in small steps from nominal to ultimate (4 batches, vacuum and temperature interlocks permitting). The aim of these measurements is to study the dependence of the electron cloud on the bunch intensity (according to simulations, this is a range of parameters in which the electron cloud could decrease with the bunch intensity). In parallel all e-cloud and pressure measurements like for the LHC25 beam

Contact people: SPS Upgrade Study Team (M. Taborelli, E. Metral, G. Rumolo, W. Höfle, V. Mertens)

- After Friday 18:00  =>  Recovery from MD, switch back to physics

- All week  =>  PS/PSB physics according to cycle availability + studies in parallel at the PS:

1) Follow up of the LHC50 high intensity studies in the PS (H. Damerau, S. Hancock)

2) Injection studies in the PS (S. Aumon, S. Gilardoni). Possibly use an EAST user in the PSB coupled to TSTPS in the PS (with a flat cycle at 1.4 GeV)

3) 150ns beams (A. Findlay, H. Damerau, S. Hancock)

Author: Giovanni Rumolo - BE/ABP
Last update: Wednesday, May 26, 2010 08:17:22 AM
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