Minutes of the ICE section

23th meeting on Wednesday 06/04/2011 (08:40-10:30, 6/2-004)

 

ICE members: Benoit Salvant (BS), Christian Hansen (CH), Carlo Zannini (CZ), Hugo Alistair Day (HD), Elena Benedetto (EB), Ewen Hamish Maclean (EHM), Elias Metral (EM), Elena Wildner (EW), Frank Schmidt (FS), Giovanni Rumolo (GR), Jean-Luc Nougaret (JLN), Kevin Shing Bruce Li (KL), Maria Carmen Alabau Pons (MCAP), Nicolo Biancacci (NB), Nicolas Mounet (NM), Olav Ejner Berrig (OB), Tatiana Pieloni (TP), Werner Herr (WH).

Present/Excused: BS, CH, CZ, HD, EB, EHM, EM, EW, FS, GR, JLN, KL, MCAP, NB, NM, OB, TP, WH, Alessandro Vivoli, Eirini Koukovini Platia, Javier Cardona, Vittorio Vaccaro.

  

1) Newcomers / visitors

- None.

 

2) Comments on the minutes of the previous 22th meeting + Actions

- None.

- List of Actions.

 

3General infos

- No particular comment from anyone.

- SL meeting:

- Reminder: Technical student deadline for the group is 14 April.

- Office space => Very tight in particular during summer when summer students come etc. => Being looked at in detail.

- BEMB:

- It was recently decided that Jean-Pol Matheys will make a BE newsletter, possibly 5 times a year => Each group will have to send him info for that.

- Paul Collier reported that the DG has negotiated a 5% flexibility in staff over the present limit of 2250 people => Discussions ongoing on how to distribute these people in the different departments.

- News on the LHC: Scrubbing run with 50 ns beam as foreseen.

- Concerning the transverse impedance measurements performed in the past in the PS, EM sent to sandraA the results of the campaign made in 2001 => See discussion and xls file below.

- BI review last Thursday (https://indico.cern.ch/event/LIU-BI-review):

- Some of us as contact persons for some instruments => BS for HEADTAIL etc., TP for Schottky...

- Is there some interest for transverse tomography? => EM to prepare or not a request. Was already asked by Massimo and Simone for MTE with 3 wire scanners. Would be very good to have 3 IPMs as in this case we could have the evolution during the cycle.

- PS WS in SS68 => It seems, according to RendeS and SimoneG, that some ferrite was installed during the Technical stop => Why? Who told them to do so? Is it linked to the vacuum observation (outgassing) discussed at some point (http://emetral.web.cern.ch/emetral/ICEsection/2011-02-23/ICE%20Min%20meeting_23-02-11.htm)?. Action1: EM to make the follow up.

- Discussion on space charge with Hannes and Yannis:

- To be confirmed that the new optics leads to less emittance growth from space charge with the ~ same tune footprint and ~ same working point?

- If it is confirmed that it really comes from the lattice, with less excitement of the resonances, then one could ask ourselves what is the best optics (as this should not be the optimum as this optics had in mind a low gammat to increase the slip factor and subsequently the coherent instabilities threhsolds). This for the SPS, but also the PS and PSB.

- Discussion with SimoneG + GR on the work on collective effects to be done for PS LIU => Idea to have Mauro Migliorati working with us (as a Scientific Associate) on the PS impedance model.

 

4) 1st LHC beam-beam observations in 2011 (TP) => POSTPONED TO THE NEXT MEETING (due to LHC scrubbing run)

 

5) Review of Hamiltonian treatment of synchro-betatron motion: Part II (KL) => POSTPONED TO THE NEXT MEETING (due to LHC scrubbing run)

 

6) Transverse Impedance Measurements in the PS in 2001 (EM-MG-RS): xls

- EM discussed briefly these measurements made in the past (2000 and 2001) with MassimoG and RendeS => We can already see large impedances measured in 2001. We never published these data as they were not clean ebough and we did not understood clearly at that time what happened in the horizontal plane: from ~ 0 in 2000 to ~ 13 MOhm/m in 2001. In the vertical plane we found in 2001 ~ 7-8 Mohm/m (and less in 2000) and Sandra et al. found last year ~ 7 MOhm/m, which seems in quite good agreement. Sandra will have a look in detail to all these data and may be combine all of them.

  

7) Actions to be taken for the next meeting

- Old actions.

- New actions:

- Action1: EM to make the follow up of the PS WS in SS68 where ferrite has been installed during the technical stop in week 13 without any recommendation from our team.

 

8)  Miscellaneous

- The next (24th) meeting will take place on 13/04/2011 => Agenda:

1) The SUSSIX code (EHM and FS)

2) Taking advantage of Sussix's sensitivity to reveal higher order mode coupling (BS)

3) 1st LHC beam-beam observations in 2011 (TP)

- See preliminary agendas for the next meetings.

 

Minutes by E. Metral, 07/04/2011.