Minutes of the GIF and GIF++ Users Meeting August 19 2008
Mar Capeans, Edda Gschwendtner, Lucie Linssen, Matteo Alfonsi, Richard Fortin, Beniamino Di Girolamo, Ivan Glushkov, Roberto Guida, Nigel Hessey, Michael Moll, Christoph Rembser, Leszek Ropelewski
Archana Sharma, Ilias Efthymiopoulos, Hans Reithler, H. Vincke, Werner Witzeling
The Agenda, documents and slides of the meeting can be found at http://indico.cern.ch/event/38368
1) A short introduction to the CERN White Paper Work-packages, in particular Work Package 7 (WP7) "Facilities and Component Analysis for Detector R&D" was given by Mar, see slides on the Agenda Page.
A future Gamma Irradiation Facility is one of the main lines of activity of the WP7.
The Work Plan for the WP7 for the Irradiation Facility foresees:
- 2008: Definition of user requirements for the facility, start of layout lead by the AB Experimental Area team;
- 2009: Preparation and approval of a Technical Design Proposal for a Gamma Irradiation Facility and procurement and construction phases
- 2010: target date "Ready for users" (May)
Mar stressed that to contact to users, their contribution and collaboration is essential for the success of the Work-Package.
2) A brief overview on the ongoing work in the current (old) GIF was given by Roberto. In his talk he focused on the status of the current RPC studies.
The RPC groups (re)started significant activities at the Irradiation Facility to
- study and understand the production of impurities (and how to avoid them) in the gas mixture and optimize the filtering stages in the LHC gas systems
- study and understand the fluctuation of the RPC chamber currents.
The results are discussed within the entire LHC RPC community, all LHC experiments participate and profit from the combined forum of the RPC task force.
One of the issues which is still not covered is the simulation of the irradiation effects.
3) In a second presentation, Mar showed the results of Questionnaire on Gamma Irradiation Facilities which was answered by the users spring 2008.
Following the questionnaire, there are two groups of users:
- one group of users for a facility where the main focus is on gamma irradiation to test radiation hardness of materials, small prototype detectors, electronic components and radiation monitors or dosimetry under a strong photon flux. This group of users demand a stronger source (compared to the old GIF) but the activities do not depend on a particle beam;
- the second user group focuses on the characterisation and understanding of long-term behaviour of (large) particle detectors for which a particle beam is mandatory.
=> the demands from both groups can be satisfied by a facility in a beam area with main focus on combined tests with source and beam during accelerator operation period on one side and a focus on irradiation during accelerator shut-down and maintenance periods.
In the questionnaire the following points were emphasised by the users:
- The facility should provide user support and comprise common infrastructures (e.g. DAQ/Trigger system, beam instrumentation etc)
- The facility should permit easy and frequent access to samples/detectors during irradiation periods and adjacent preparation areas
- The facility should permit to tune dose rates by factor of ~10^5
- The facility should be operational from 2010 for 3-5 years
With the input from the users, a document "The GIF++ Gamma Irradiation Facility at CERN" was prepared, is available at http://project-wp7.web.cern.ch/project-WP7/WP7_DOCUMENTS.htm and was discussed in this meeting, see points 4 & 5 of the minutes.
More information on the results of the questionnaire of all facilities being discussed in the Irradiation Facilities Working Group framewrok can be found in Lucie’s recent presentation at the CERN Accelerator Technical Committee: http://ab-div.web.cern.ch/ab-div/Meetings/ATC/Welcome.htm -> ATC Minutes.
4) A summary of the document "The GIF++ Gamma Irradiation Facility at CERN" was presented by Christoph (document: http://project-wp7.web.cern.ch/project-WP7/WP7_DOCUMENTS.htm ).
The present users supported the document and in the discussion ( point 5) of the agenda) the following points were decided/agreed:
-> a future facility should be located at the SPS: Beam of secondary particles, Muon beam, about 10^4 particles per spill, 10cm x 10cm, beam momentum order(100GeV). Possibility of other beam particles.
-> the layout, zone dimension should suit to host large objects (questionnaire: 3m x 1.4m x 0.5m), thus the size should be ~ 10m (along the beam) x ~7.5m (lateral to the beam) and shall be able to accommodate detector objects of up to 3 m total height. Fast and easy access, even for large objects is mandatory to improve duty cycle. The zone should be temperature controlled: tent-structure
-> the source should be a 137Cs source as old GIF (662keV photons) but factor 10 higher flux (no Co source as thicker shielding requires and source lifetime too short).
-> there should be a second irradiation beam defined by separate collimator.
-> The facility should also prepare adequate infrastructure to cool silicon detectors
* June-Sep’08: evaluation of scenarios and design proposal
* Sep’08 – March’09: Preparation of Technical Design Proposal (AB Dep.)
* Sep’08-Feb’09: Design of final infrastructure (not related to the particle beam)
* Apr’09: Approval of Technical Spec’s
* May’09-Dec’09: Procurement and Construction
* Jan’10-May’10: Infrastructure Commissioning
* May’10: Target date “ready for users”
* Dec’10: First report of results
-> Mar and Christoph will modify the document "The GIF++ Gamma Irradiation Facility at CERN" according to the decisions made in this meeting. The modified note will be sent to the users within the next weeks for a final round of comments/suggestions/corrections;
-> Edda Gschwendtner will start to work on a proposal from AB EA;
-> Collection of information for individual parts (e.g. source) will start; a list of possible deliverables will be prepared.
-> a follow-up meeting will be organised in 2-3 months from now.
Minutes by Christoph Rembser, 24.8.2008
There are minutes attached to this event.