From Grzegorz.Wrochna@fuw.edu.pl Tue May 11 12:52:57 2004 Date: Tue, 11 May 2004 18:04:40 +0200 From: Grzegorz Wrochna To: Walter Vandoninck , Archana.Sharma@cern.ch, Ian Crotty , Antonio Ranieri , Giuseppe Iaselli , Flavio Loddo , Darin Acosta , Jay Hauser , Jan Krolikowski , Maciek Kudla Cc: Wesley H. Smith Subject: RPC @ tests beams 2004 Dear Colleagues, I would like to summarize briefly several discussions which happened these days concerning RPC tests this year. People involved were: D.Acosta, I.Crotty, G.Iaselli, A.Ranieri, A.Szarma, W.Vandoninck, G.Wrochna. There are two periods with 25ns beam available this year: 14-20 June and 28 Sep. - 4 Oct. This is the very last opportunity to test our electronics before the production. Being under a pressure of the tight production schedule and facing the situation that the barrel chambers will not be provided for the test beam in June, we have agreed to the following plan. 1. 14-20 June period will be devoted to test the RPC trigger electronics with RE and CSC chambers. Goals: - check for RPC/CSC interference - test RPC Trigger electronics, especially all functionality of the Link Board - test RPC - CSC connection 2. 10-20 July (?) at Bari (or at ISR) - tests of RPC Trigger electronics with the cosmic stand of the barrel RPC. Goals: - test those functions which do not require 25ns beam, especially the DCS part of the system - gain practice with RPC monitoring via Link Boards - work on the Sorter 3. 28 Sep. - 4 Oct. - full chain test of the RPC trigger electronics with the barrel RPC. Goal: - validate trigger electronics for mass production Let me elaborate on each period. ad 1. 14-20 June The plan is to attach one RE1/2 to the CSC and connect it with one or two additional RPC to the trigger electronics. 3 sets of gaps for RE1/2 have been shipped from Korea to CERN. Two of them exhibit detached spacers. Suspected reason is depressurising test of cargo. All 3 chambers have been assembled. The hope is, that even those with affected gaps will be useful, although the performance is not guaranteed. There is also one set of old gaps which could be used as a backup. 10 Front End Boards should be available by the end of May. Falvio is working on them and he is warmly welcome to join the test. The test is planned in the X5/CSC area. Gas and HV cables could be taken from GIF. Also HV and LV supplies could be borrowed from the GIF setup. Archana kindly agreed to look for that. The final signal cables are not available. There are 3 possible options: - old DT type cables used at the test beam last year - CSC type skew clear cables - cables of the type used in the ISR for barrel RPC. Walter agreed to look at these possibilities. Warsaw group will install connectors on the trigger side. RPC Trigger electronics could be installed in the CSC rack, on the balcony, out of the barracks. Two crates are reserved for CSC. A space for one 9U crate for the RPC trigger could be available. RPC trigger computers could be located in one of the CSC barracks. The main user of the beam is Tracker located downstream the beam. They need mostly muons, but in order to get high luminosity they run pions through an absorber placed next to their area. This is not convenient for CSC/RPC and we consider putting another absorber between two CSC. The trigger will be provided by beam scintillators. After running in, the CSC trigger could also be used. The RE group (Archana, Walter and Ian) will take care of running the RPCs in terms of gas and HV setting. Chamber current will be monitored, but there will be no separate readout. The only way to collect the data is through the Link Boards. It is not an ideal solution, because we have to debug two things at the time, but is seems we have no other option. We decided to try to integrate the RPC and CSC readouts. Both are based on XDAQ, and the experts are encouraged to get in touch (Michal Pietrusinski on Warsaw side, Darin will provide CSC names). The RPC endcap core group is permanently at CERN. Darin or someone else from the CSC group is also at CERN. Most of the CSC group will come a week before the beam. Also Warsaw group will arrive at CERN on 6 June. ad 2. 10-20 July (?) at Bari (or at ISR) Practical arrangements need to be discussed. An important ingredient is the request from Pino to get the RPC group more accustom to the RPC monitoring mechanisms and the Link Board in general. This request is very much appreciated by the trigger group :) We also need to make sure, that the system can be used for monitoring the chambers, before the Counting Room is equipped. One sector triggering with a local cosmic DT trigger, temporary DAQ for RPC monitoring, etc. are among the questions to be thought of. ad 3. 28 Sep. - 4 Oct. - full chain test of the RPC trigger electronics with the barrel RPC, with final chambers and their final FE electronics, final LV/HV system, full trigger, DAQ and DCS chains (preproduction prototypes). There are two possibilities: - X5 area is reserved for ATLAS RPC and there are discussions going on to include the CMS RPC there. An advantage of this solution is that substantial part of infrastructure is already available. - H2 beam at Prevessin is reserved for CMS HCAL and DT. An advantage here would be a possibility to make joined tests with DT and with HO. However, one should keep in mind, the the primary goal of this beam test is to validate the trigger electronics for mass production and this goal should not be compromised. It means that e.g. the joined test with HO could be moved to a lab. People involved should stay in a close contact by electronics means, but we also need to meet in person more frequently. The first occasion is the CMS Week 7-11 June, which is just the week before the test beam, when all people involved should already be present at CERN. I am sorry for this lengthy letter, but the time is short and we need to be extremely well prepared to do the job. In spite of many difficulties ahead, I believe that the goals could be achieved. I thank all of you for active participation in the discussions. Best regards Grzegorz -- _____________________________________________________ | | | dr hab. Grzegorz Wrochna http://cern.ch/wrochna | | Soltan Institute for Nuclear Studies | | Hoza 69 e-mail: wrochna@fuw.edu.pl | | PL 00-681 Warsaw tel: +48 22 628 18 93 | | Poland fax: +48 22 621 28 04 | |_____________________________________________________|