CM26 March 2010Slide 1 EMR Status o Intro o Construction o Magnetic shielding o Electronics o Prototype Cosmics test o Schedule Jean-Sebastien Graulich, Geneva

EMR: Electron Muon Ranger  This report is about a team work Como/Trieste: Michela Prest, Erik Vallazza, Daniela Lietti, Davide Bolognini University of Geneva: Franck Cadoux, Florian Maschiotti, Laurent Nicola, Coralie Husi Pierre Bene, Stephane Debieux Havard Wisting, Kaspar Rothenfusser Ghislain Grégoire  A lot happened, trying to summarize Refer to previous presentations for more details EMR talk at CM25 EMR Construction Status at VC128 EMR Cosmic Tests at VC129 EMR Installation talk at CM2 CM26 March 2010Slide 2

CM26 March 2010Slide 3 Daniela Lietti CM25

Construction  Main Steps Cutting to length – done Gluing fibers (up to 20 per day) Layer Assembly Module Assembly CM26 March 2010Slide 4

Integration  Extremely compact assembly CM26 March 2010Slide 5 Outer Box  Difficult access to PMT and electronics after Assembly  Just enough room for local shielding  Heating of electronics (FPGA, HV dividers, etc FEB Flex connector The PMT is attached to the board Shielding not shown

Magnetic Shielding Issue  Situation looked difficult Impossible to shield locally CM26 March 2010Slide 6 3D model from Ghislain (OPERA 3D) EMR thickness Plot Field vs PMT location

Magnetic Shielding Solution  First: Global shield 50 mm thick iron plate EMR is moved back (reduce acceptance)  Second: Local shield on PMT CM26 March 2010Slide 7 EMR PMT axis

CM26 March 2010Slide 8

Magnetic Shielding Summary  The problem was more serious than originally thought  We have now a satisfactory design Large iron reflector between KL and EMR EMR is moved back by 50 mm Local shielding (1m) around each PMT  We had to stop detector production 2 months delay  The PMT-Fiber coupling had to be modified  We are ready to resume production CM26 March 2010Slide 9

Electronics  Each bar is read out on both side but with independent chains  Digital readout Each bar is connected to one pixel of a 64 channels MultiAnode PMT The PMT is connected to a Front End Board (FEB) where the signal is amplified and discriminated The logic signal from the FEB is sampled by a Digitizer and Buffer Card (DBC) The DBC stores the data for the entire duration of the spill The DBC is read out through a VME Controller card at the end of the spill  Analog readout On the other side All the fibers from each are bunched together and coupled to a single 1” PMT The output of the PMT is connected to one channel of a 500 MHz sampling ADC (CAEN V1731) The data is buffered in the ADC and readout at the end of the spill CM26 March 2010Slide 10

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Electronics Status  FEB Designed and produced by Trieste/Como Based on existing FEB for another experiment AD) Recently modified and tested to use the MAROC amplifier/discriminator chip (instead of Gamma Medica/Ideas VA64TAP)  Digitizer and Buffer Card Design in progress in Geneva  VME Controller Based on general purpose VME board provided by Trieste/Como  Clock and Trigger distribution Under discussion  Sampling ADCs In hand in Geneva CM26 March 2010Slide 12

Cosmics Test  One full module (2 layers) operational in Geneva  DAQ provided by Como/Trieste  Many Thanks to Daniela Lietti and Davide Bolognini CM26 March 2010Slide 13 2 X-Y Silicon strip detectors 10x10 cm 2 Trigger Scintillator 10x10 cm 2 2 EMR Layers

The first EMR Module CM26 March 2010Slide 14 X Y Single anode PMT All fibers bunched FEB Multi-anode PMT coupled to FEB

Analysis – Prerequisite  Using the prototype Front-End Board based on the VA64TAP chip Need to scan the sampling time to determine our working point CM26 March 2010Slide 15

Efficiency Standard PMT Efficiency ~93 % Green Enhanced PMT Efficiency ~98 %  Testing different configurations High Voltage scan With/Without Optical grease Standard/Green enhanced PMT  Two independent analysis Trieste/Como : Michela Prest and Davide Bolognini Geneva: Havard Wisting

Cross talk  Obvious cross talk between channels Between anodes Partially due to the PMT alignment Not only ! Between fibers ? Can improve fiber isolation… CM26 March 2010Slide 17

Cosmics test Summary  Currently taking data at about 3 Hz  Efficiency Measurement consistent with First prototype results: ~97.5 %  Cross talk is a serious issue  Next Steps Integrate the single PMT readout in the DAQ Need to migrate from SBS Bit3 to CAEN VME-PCi interface first Test with the first production module 1.2 mm fibers More precise PMT lodging Define automatic test procedure for QA during production CM26 March 2010Slide 18

Project Plan  Running full speed, we need 6 working days to produce 1 module (2 layers) => Production time: 7 months  EMR production should end in October 2010  Digitalization and Buffer card design test and production Estimated to 6 months  We are considering a partial delivery to RAL this summer in order to have an early test of integration in the DAQ  We also depend on other experiment pressure on our Engineer/Technician staff CM26 March 2010Slide 19