From: jmartin@nuclear.uwinnipeg.ca Subject: minutes of phone call from Thursday Date: Sun, September 9, 2007 10:07 pm To: cymru@triumf.ca,trlr@triumf.ca,ewb@triumf.ca,"Rick Baartman" ,"Akira Konaka" ,schmor@triumf.ca,krab@triumf.ca,dutto@triumf.ca,masuda@post.kek.jp,spage@cc.umanitoba.ca,"Nigel Lockyer" ,vanoers@jlab.org,mgericke@jlab.org,amicherd@nuclear.uwinnipeg.ca Dear all, See below for the minutes of the meeting. From these minutes, I intend to draft a slide or two for the TRIUMF board of management meeting, which I would then circulate to this list for comments. Regards, Jeff Minutes of UCN phone meeting 9/6/7. JWM Present (that I could hear): J. Martin, R. Baartman, P. Schmor, A. Konaka, C. Davis, A. Micherdzinska, W. van Oers After some discussions, we settled on the following options, distinct from the white paper and from the initially presented options at the phone meeting: 1) Before 2010: Operations with existing BL4A at any reasonable current would require significant rearrangement and recommissioning. Such efforts would likely not be worthwhile given the work involved and the short timescale. A preferable strategy would be to focus short-term efforts at KEK/RCNP to develop a future UCN source for TRIUMF. 2) After 2010: We discussed two possible options for beam delivery to the TRIUMF UCN source: a) BL4 port. Some potential advantages exist in relation to ISAC 3 developments. BL4A will be built up (with significant shielding) for a bend for ISAC BL4N, so that significant shielding would be required anyway. Additionally, there will be a new high-power beam dump constructed in ISAC 3 target hall, which could potentially be used by UCN to achieve pulsing. Disadvantages are that UCN would share beam with ISAC 3. However, this can be ameliorated through various schemes. The most viable scheme suggested so far involves the use of two kickers. The first kicker would separate UCN from ISAC on kHz scale (which might also involve kHz operation of the ion source). The second kicker (in the UCN line) would achieve UCN duty cycle (1 min on / 3 mins off) by switching between UCN and the beam dump in ISAC 3. The UCN source could be located either close to the existing BL4A, or even in the future ISAC 3 target hall. b) BL5 port. This option requires construction of new port that does not conflict with probe extraction for the cyclotron. Additionally, a beam dump would be required to achieve beam pulsing for UCN. However, the advantage is that UCN would be completely decoupled from ISAC 3 running. It was discussed that serious shielding and heat transport simulations should be performed, and that remote handling would be required to periodically replace the spallation target. Jeff presented the way these issues are handled for the UCN project at LANL (which is certified for 100 uA instantaneous current, 10 uA average, at 800 MeV). Shielding at LANL consists of 3 m steel and 2 m concrete. The spallation target is tungsten and is cooled with compressed He gas. Remote handling is achieved by first removing one shielding block, then pulling the target out through a custom-made shielding block. The target is then placed in a cask. For both options a) and b) above, there are potential space conflicts with the e-linac project. This is for the BL4A and BL5 options. Jeff agreed to contact Shane K to discuss what options are available based on current e-linac designs. -- %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% % Prof. Jeffery W. Martin Phone: (204)786-9443 % % Physics Department Fax: (204)774-4134 % % University of Winnipeg URL: http://nuclear.uwinnipeg.ca % % 515 Portage Avenue % % Winnipeg, MB R3B 2E9 CANADA % %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%