EDMS Id: 1174226
Minutes of Beam Loss, Protection, Transfer Lines LIU-SPS Working Group Meeting
Notes from the meeting held on
01 December 2011
Present: Hannes Bartosik, Karel Cornelis, Verena Kain, Malika Meddahi, Alessio
Mereghetti, Oznur Mete, Helga Timko, Helmut Vincke, Jorg Wenninger.
Excused: Wolfgang Bartmann, Brennan Goddard, Yvon Muttoni.
1- Provisional Layout Drawing for the LSS4 Upgrade – Frédéric Galleazzi
Frédéric presented the integration studies in LSS4 for LIU project (slides). The requested
and proposed positions of the new scrapers for each of the transverse axis and the
locations of the two new vertical bumpers were discussed. The current and modified layout
drawings of the upgrade areas can be found on the provisional drawing.
2- Update on the Fluka Work– Alessio Mereghetti
Alessio presented the current status of Fluka studies concerning several regions on SPS
(slides) such as TI2/TI8, present scraper region on LSS1 and LIU scraper region for LSS4.
The Fluka studies are focused on the geometry defining for the concerned regions. The
first simulations are going to be run over the Christmas break. Before starting with the
simulations Alessio will go through the geometry in collaboration with Helmut and Verena.
The estimation of the load on the inner absorber of the TIDVG in case of the most critical
LIU beam is suggested.
3- Beam Position Stability and Follow-ups on LSS4 Scrapers - Öznur Mete
Öznur presented the first results of the possible orbit fluctuations on LSS4 due to several
systematic error sources (slides). In addition she reported on the follow-ups such as the
critical clearance situation of BTVE.41895 during the vertical bump under Q26 optics; and
the status of the ECX4 and ECA4 areas in terms of the beam loss and radiation. Need for
an access was reported to make a recent inventory of the SEU sensitive equipment for the
area.
4- A.O.B.
The LIU BL-P-TL meetings have been finalized for 2011 due to the busy calendars of the
members in the end of the year.
5- LIST OF ACTIONS

Action for scraper studies: Frédéric Galleazzi.
- The additional bumpers were identified as MLSH-type since their length was a sufficient
reference for the vertical bumpers to be added. For the final stage the two additional
MLSH (MPSH.41673, MPSH.41992) should be rotated by 90o in order to implement them
as “MPV” type magnets.
- The available space dimensions (x,y,h) will be given for the critical elements (e.g.
Scraper.41897).
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
Action for scraper studies: Alessio Mereghetti.
- Estimation of the load on the inner absorber of the TIDVG in case of the most critical LIU
beam.
 Action for scraper studies: Brennan Goddard.
- Communication of the map of the dumped particles on TIDVG in case of the most critical
LIU beam with Alessio.

Action for scraper studies: Oznur Mete.
- Consider the BPM reading errors and resolution as well during the investigation of the
trajectory stability.
- A first estimation of the radiological impact factor for the scraper activities on LSS4 can
be rescaled from the values previously studied for the CNGS, TPSG.
- Invite Jorg to the next LIU meeting to be informed of the previous beam loss
measurements for CNGS, TPSG etc.
- Meet Frédéric for the final stages of the provisional layout drawing.
- Resolve uncertainty on the BTVE axial position for the circulating beam.
- Organize an access to SPS-LSS4 EXC4 region and invite several colleagues.
- In case the design of a new corrector magnet is needed, organize a discussion with the
magnet colleagues.
Next meeting:
Next LIU BL-P-TL meeting: 12th January 2012, 10:30 – 11:30, 865/1-D17.
Tentative Agenda
- An update on the critical elements on the provisional drawing (Frédéric Galleazzi)
- Preliminary results of the Fluka simulations for TI2/TI8 (Alessio Mereghetti)
- Beam loss and protection aspects of LIU-SPS scrapers activity (Öznur Mete)
Öznur Mete
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