Minutes of the Linac4 Technical Design Committee

meeting no. 6

date: 10 October 2006

present:

AB/RF	M. Pasini, J. Broere, F. Gerigk, C. Rossi, M. Vretenar
AB/ABP	G. Bellodi, A. Lombardi, E. Sargsyan, D. Kuchler, Th. Meinschad, R. Scrivens
AB/BI	R. Garoby
AB/CO	J. Serrano
AB/BT	W. Weterings, B. Goddard
AB/OP	K. Hanke
TS/CV	Y. Body
TS/MME	Y. Cuvet
TS/CE	A. Lopez-Hernandez
TS/SU	M. Jones
AT/MEL	T. Zickler, W. Kalbreier
AT/MTM	W. Venturini
SC/RP	M. Silari, E. Mauro

agenda

1. News from Linac4 (M. Vretenar)
2. H^- injection layout in the PSB (B. Goddard)
3. Magnets for Linac4 (T. Zickler)
5. Tour de table
6. next meeting

1. News from Linac4 (M. Vretenar)

The Linac4 project will be part of the Medium Term Plan that will be submitted to the Council at the December 2006 meeting. The details are not yet clear, but it is likely that the funding for the first year (2007) will be reduced with respect to what foreseen in the preliminary financial plan for the project. Normal funding should be resumed after 2007, when the financial situation of the LHC will be clearer. About the location of Linac4, the three options presented at the previous meetings (South Hall, Linac2, Mont Citron) are still on the table. A meeting with AB, TS and RP management has been organized for November 21, where all the options will be presented taking into account advantages and disadvantages. Only 2 contributions to the Technical Design Report are still missing (they were received after the meeting), and the draft of the TDR is now available at the address: http://vretenar.home.cern.ch/vretenar/Linac4_TDR.html . Contributors are invited to check their part. Small modifications are still possible until end October, and the final revision should be completed by mid-November. All contributors are thanked for their remarkable work and in particular G. Bellodi and F. Gerigk for co-editing the text. In spite of the excellent quality of the document, it looks like there will be the need for an updated version of the TDR to be published at end 2007 as a CERN Yellow Report (with final layout, machine and line design).

Discussion:

• R. Garoby mentioned that this document will be useful for the management to look for external in-kind contributions to the project.

2. H^- injection layout in the PSB (B. Goddard)

A very preliminary layout of the H- injection area has been defined, considering all the new elements to be installed in the PSB injection section. The issue of the H0 dump has been analysed with a certain detail, and the conclusion is that a dump external to the dump is not possible with the present geometry. However, several issues still remain to be checked or solved.

In the discussion, M. Silari pointed out that the radioprotection issues of the internal dump have to be studied very carefully, and he repeated his preference for an external dump. F. Gerigk commented that ISIS has a higher beam power than Linac4 and uses an internal dump, and suggested to contact the RAL machine experts for more data on their dump.

3. Magnets for Linac4 (T. Zickler)

In total, about 100 electromagnets will be needed for Linac4. Important issues that were considered are the choices between pulsed and CW operation and between water and air cooled magnets, especially in view of the SPL operation at higher duty cycle. For the quadrupoles, air cooling with pulsed operation has been preferred. The dipoles are water cooled, and slow pulsed operation is possible. A common design is proposed for all steering magnets in Linac4. The existing magnets in the part of transfer line that will be reused for Linac4 have been checked, and most of them can be used without modification.

Tour de table

• K. Hanke reported that some short beam profile monitors have been recuperated for the chopper line, and the vacuum chamber design is now being modified in order to have them in the line from the start. There are still problems in the communication with the BI Group, and technical problems are being addressed in a series of instrumentation meetings.
• F. Gerigk reported that he has received an offer for the shielding of the transfer line in the PS area. For a factor 30-40 attenuation, cost is 7 k$, for a factor 130 the cost goes to 11.5 k$.
• M. Silari introduced E. Mauro, the new fellow who is going to study radioprotection issues for Linac4.

next meeting:

Tuesday November 28th, 14:00, room 354 1-001 (last meeting of the year, and probably last one with the present format)

-- MaurizioVretenar -