WP#63 30/07/2008 -------------------------------------------- Wednesday 30 July 2008 West Coast East Coast W.Europe Japan 07.00 10.00 16.00 23.00 1. News 2. PCMAG/fieldmap 3. LP fieldcage, endcap/panels, laser etc - status fieldcage - Dan's URL: http://www.lepp.cornell.edu/~dpp/linear_collider/LargePrototype.html 4. Electronics 5. AOB Present: David Attie Ties Behnke Klaus Dehmelt Ralf Diener Bakul Gaur Christian Grefe Stephan Haensel Xavier Janssen Alexei Lebedev Lucie Linssen Takeshi Matsuda Dan Peterson Ron Settles Akira Sugiyama Jan Timmermans --Anybody forgotten? Summary ----------------------- 0. Slides are at the agenda site: http://ilcagenda.linearcollider.org/conferenceDisplay.py?confId=2910 00. After repeated requests for writing minutes: - first apologies by Jan for not having been able to produce them in the recent past - as it is difficult to take notes for minutes and chairing the meeting Jan calls for volunteer(s) to write minutes - it would already be helpful if people making a presentation could send Jan a short 'minute-like' summary of their presentation+discussion. 1. News. - There was no special news item presented 2. PCMAG/fieldmap. - In the last 2 weeks a few e-mails circulated re the validity(/quality) of the existing field map after the rotation by 180 degr. of the magnet, due to the presence of magnetizable material in the neighbourhood of the magnet, e.g. concrete wall or support blocks. Christian has observed in the present fieldmap an azimuthal effect of ~2mT which may be due to the supporting concrete blocks. He suggests to make some cross-check measurements on a small set of positions after the magnet rotation. He also promised to produce similar curves for B-field integrals as in Ron's note (see copy on agenda page) from the current fieldmap. - Klaus Zenker, a summer student, did some first calculations on the influence of a massive iron piece, outside the magnet but close to the coil on the field components (see slides on agenda page). Christian promised to do also some further analytical calculations. 3. LP endcap, fieldcage and panels Endcap: ------- -Dan reported on the last steps in the production, see http://www.lepp.cornell.edu/~dpp/linear_collider/LargePrototype.html where several details are given. The endplate corrections will finally be finished only 'today' because of messing up of paperwork. 10 out of 28 received backframes have been inspected. Many parts need extra machining of outer-radius surface and repositioning of holes. 4 "good" Micromegas-type backframes will be sent to Saclay 'this week'; the 3GEMNogate-type is also "good"; 1 (out of 21) 3GEMG-type is "good" and will be sent to Bonn. The inspection of the mounting brackets will be done within a few days. Fieldcage: ---------- -Klaus Dehmelt reported that the fieldcage is finished and that final processing of the (temporary) endplates intermediate flange is under way. He expects to have the fieldcage at DESY now very soon. -Bakul Gaur presented the HV powering scheme of the cathode, FC resistor chain and FC termination plate (see slides on agenda page); for the latter two alternatives (with and without separate HV supply) were shown. Also the possibility of a 2nd field strip supply beyond the termination plate is foreseen. People are invited to send comments on this proposal. It is foreseen to have a separate supply for the cathode and the FC resistor chain; this would allow eventually to measure ion-backflow currents on the cathode. Panels: ------- -no news on panels 4. LP1 electronics. - No one from Lund present to report. After the meeting (on 5 August) Leif informed that the updated estimated total costs for the 10,000 channels scenario is more or less matching the available money. 5. AOB. -Ron presented the status on MOA signatures (see slide on agenda page): Brookhaven and KEK have now signed as well. Dan was told that his lab director was going to sign 'today' a version of the MOA that contains a clause on publications and equipment property. - Stephan Haensel presented a few questions related to the Silicon envelope (see his slide); he provide himself the following summary below (thanks Stephan). - Alignment System * WP4 is in charge for alignment strategies - Klaus is in contact with the DESY survey-team * survey-team uses mirrors which are too big to fit between TPC and Magnet -> another solution has to be found for the silicon modules - SiLC support * Karlsruhe can start with the design and construction of the SiLC support not before end of September -> my guess: it will be finished in November (has to be verified) * Vienna could build a simplified support till end of September -> the LPTPC community decided, that we can wait for the final support structure from Karlsruhe Ties ? :"it should be manageable to remove the interfering LP parts and even the TPC-support out of the magnet to integrate the SiLC system in November" - Combined Readout * Klaus organises a meeting to start working on the implementation of the SiLC detector modules into the common DAQ of the LP (mail already out) -Next (EVO/phone) meeting: 13 August 2008, usual time 16:00 CET