From settles@mppmu.mpg.de Sat Dec 1 11:54:33 2007 Date: Sat, 1 Dec 2007 11:54:12 +0100 (CET) From: Ronald Dean Settles To: lctpc@desy.de Subject: Corrected summary of WP phonemeeting #44 21.11.2007 Dear lctpc friends, Dan had some corrections to the draft minutes; the revised summary with Dan's changes indicated by "(DC)" is below and on the website... Bon weekend, Ron -------------------------------------------- Wednesday 21 November 2007 West Coast East Coast W.Europe Japan 06.30 09.30 15.30 23.30 --Present: -Paul Colas -Ralf Diener -Madhu Dixit -Lea Hallermann -Dean Karlen -Alexei Lebedev -Takeshi Matsuda -Dan Peterson -Oliver Schaefer -Peter Schade -Ron Settles -Akira Sugiyama -Jan Timmermans --Anybody forgotten? Summary ----------------------- 0. For the slides, see http://ilcagenda.linearcollider.org/conferenceDisplay.py?confId=2377 1. News For the MOA, RS reported that two more signatures have been received and several groups are nearly ready. See the above website for the latest (fourth) version of the MOA and a draft for the Addendum2007. The groups have been and are being asked for feedback. The evolution: 1)the first MOA version was sent to the CB members on Tue 21 Aug 2007 14:04:44 +0200 (CEST), 2)the second on Fri 14 Sep 2007 11:52:03 +0200 (CEST), 3)the third on Tue 2 Oct 2007 13:13:59 +0200 (CEST) and 4) the fourth on Sat 27 Oct 2007 11:26:49 +0200 (CEST). Most groups were happy and there have only been minor changes, and if you haven't done so, please send your signature by normal mail to me Ron Settles Max-Planck-Instute for Physics Foehringer Ring 6 D-80805 Munich and I will put together a master version and send all groups a copy. 2. LP cosmic trigger The cosmic-trigger status was summarized by Takeshi and Paul; a detailed write up is on the above meeting-website. The production of the counter slabs is starting in Moscow with expected delivery aroung end January; the MPPCs have been delivered; the Saclay team has been identified and has started setting up for the first tests. 3. LP endcap and fieldcage Dan went through the latest items on his website: http://w4.lns.cornell.edu/~dpp/linear_collider/LargePrototype.html. For details, click on -"page of current drawings" -"page of Assembly configurations" -"page for the Gas Seal test" -"page for the Stress Relief tests Items covered during the phonemeeting were as follows: ----------------------------------------------------- -Vendors Dan is visiting vendors and will probably decide on the fastest which will take about 8 weeks to manufacture an endplate. -Light holes: see "20071109-6080-102-endplate-drawing.pdf", page #5. (DC)The holes are provisional. Dean will send specs. -(DC)Dowel holes for the endplate: see "20071109-6080-102-endplate-drawing.pdf", pages #9,10 (for the "B-holes", see page #3). (DC)These dowels define the position of the backframe to the endplate and are final. -Other holes: gas- and "fun"-hole positions are also provisional, and LP users are asked by Dan to check and provide input. -The gas holes were were discussed: IN one side and OUT on the other side should be diametrically opposed. In principle IN should be "down" and OUT should be "up", but if the chamber is rotated for cosmics, "down" and "up" are in the horizontal plane. It was thought that this is not important after several flushings of the volume. -(DC)Module Back-Frames: see "20071109-6080-104-backframe-drawing.pdf". Side holes have been added for for strain relief. Input from Akira and Paul is required for dowel holes on the inside face to locate the pad board on the back-frame. Manufacture in the lab machine shop of a first set of back-frames has started. This is a total of 6 back-frames, 2 each for Akira, Paul and Martin. -(DC)Torque to compress the o-ring: Dan accepts the 5mm screw size; the required force is 15% of yield. Field cage threaded inserts must pass a test of 3600N pull-out force. See Dan's website for details. -Field cage: the bolt radius 375mm is o.k. and the bolt size of 5mm is o.k., the latter from the torque measurements above. The other dimensions have also converged to agreement between Cornell and Desy. -Field Cage Termination Plates, again on Dan's main page (near the bottom). Work is in progress. -Alexei asked whether the fieldcage voltage tests have been done in Ar, since air is much more stable. Peter answered that the tests in air take into account this difference. -Alexei's laser was discussed. Alexei will send a drawing. He proposes that a mirror system brings in the laser light to his mirror-bundle on the fieldcage wall from the cathode side (small side of PCMAG). Corresponding holes in the cathode plates (external endplate and drift-field termination plate) will the needed at the radius of the mirror bundle; the mirror bundle will be mounted on the inside of the fieldcage wall. Dean said that the 266nm-10mJ/pulse laser used for his two-track measurements at Desy can be used for Alexei's system (Desy will check that it is still operational). 4. Testbeam news -Madhu reported that there is renewed interest in Fermilab to have the Triumf 2-T magnet for the Fermilab testbeam. The question for us is whether 2T is sufficient. Takeshi will look into details for the 3T Amy magnet, which is another possbility. Ron reported that Cern and Slac are also looking into testbeam possiblities with ILC-like bunch structure. 5. Next phonemeeting: WP#45 on 6 December 2007, usual time.