Minutes PSB Upgrade WG Meeting 4^th September 2014

Participants: E. Benedetto, J. Borburgh, R. Froeschl, J. Hansen, D. Hay, M. Kowalska, B. Mikulec, A. Newborough, B. Riffaud, A. Sanz, C. Zamantzas, L. Zuccalli.

Agenda (https://indico.cern.ch/event/337701/):

1. Approval of Minutes

• The minutes of the last LIU-PSB WG meeting #130, available here, were approved.

2. Communications

• TDR: Contributions have been received from all the WP holders and the TDR is almost complete. The executive summary edited by M. Meddahi has to be sent next week to F. Bordry to be presented at the upcoming Council Meeting.
• WBS: M. Meddahi is updating the WBS, which is accessible on EDMS. The new project organigram can be found here.
• A cost and schedule review is planned for March 2015.
• Input for projected 2014 spending: The deadline has been extended to Wednesday next week. Your input is indispensable.
• The Finemet review is taking place next Tuesday.

3. Follow-up of Open Actions

• E. Benedetto: Write specification document for the turn-by-turn profile measurement. This is required to allow BI to complete their TDR contribution. E. Benedetto will prepare this document for next week.
• C. Zamantzas: BLM integration issues. C. Zamantzas has sent the information on the newly installed BLMs in the PSB rings with their supports to J-M. Lacroix. The only location that is missing is the special support in section 15; once OP will accept this position, he will send the information to J-M. Lacroix. The presentation today will treat the BLM integration in the future PSB injection section - therefore this action can be closed.
• J-M. Cravero: Check sensitivity and stability of the DBS correctors operated at low current. E. Benedetto has tested these beamscope dipoles at low current. The stability at flat top seems adequate, but the rise-time is different for the 3 dipoles. She is waiting for feedback from J-M. Cravero to understand if the rise-time of the power converters could be modified.

4. Integration of BLMs in the H- Injection Region

B. Riffaud presented the current status of the integration of the LHC-type BLMs and diamond BLMs in the future H- injection area. The area is extremely crowded, and in certain regions the margin is only in the mm range. LHC-type BLMs should be installed close to BSW1 (1 each for top and bottom rings), to the stripping foil unit and to the internal H0/H- dump; at the first and last mentioned position diamond detectors should be placed as well (1 per ring). To allow rapid interventions (hot area!), the proposed solution consists of moveable supports for the BLMs on the outside of the ring. The distance of the BLMs to the circulating beam can be seen on slides 10+11.

B. Mikulec commented that due to the complexity of the region and the lack of space there were not many other options and that the proposed solution seems very nice.

The question was asked how it could be assured that the BLMs would be turned back to their operational position after an intervention; C. Zamantzas said that an indexation system could be implemented.

J. Hansen was worried about the available space to access the collars, but this space is not restricted by the BLMs thanks to the proposed solution.

For the diamond BLMs (fixed onto the LHC-type BLMs) there are 2 articulations foreseen; both have to be unscrewed at the same time.

A. Newborough said that he would clearly prefer if the BLMs at the internal dump location would not be fixed onto the bending magnet. L. Zuccalli and B. Riffaud said that they would investigate whether these BLMs could be fixed on the green support beam, which seemed feasible at first sight. The option to place the BLMs at the inside of the rings seems not ideal - on the design drawings the bus bars, cables etc. are not yet shown and should be included at a certain point to provide the full picture of the integration difficulties.

5. AOB

• D. Hay: During the next end-of-year technical stop he is planning to lift some regions of the false floor to finish off cable identification. He said that in principle the machine will not be locked out completely. There will be restricted access only, and he is about to ask for a derogation to proceed with the cable identification work. 2 weeks are needed. A meeting is planned mid-October to discuss this. Another meeting on the future rack installation will take place end of September.
• A. Newborough brings up the issue that it was discovered recently that the PSB reference magnet was not the same as the main bending magnets (it was a prototype and has shorter coils). Today this is not a problem, but for 2 GeV operation it might well be one. Discussions with the main players should be organised soon, and the subject will be presented to the LIU-PSB WG in October. A. Newborough also informs that M. Buzio is asking for input for the B-train concept. Please read his part of the TDR carefully and send your comments as soon as possible.
• C. Zamantzas would like to know the required dynamic range for the BLM output; for the current situation and 2 GeV operation. He should first check the simulations done by S. Damianovic; maybe simple scaling could be applied. Otherwise this should be discussed with OP and ABP.

-- BettinaMikulec - 03 Sep 2014