MaPMT Readout Workshop / Introduction MaPMT Workshop Imperial College 26/27 June 2003 Franz Muheim University of Edinburgh

2 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Workshop Agenda & Goals o Outline of MaPMT project o Reports/Presentations –MaPMT/Beetle studies –Photo detector integration issues –Possible Readout schemes –Level-1 Electronics, PINT results –Plans for this summer o Define MaPMT read-out project –Produce list of tasks necessary to get job done –Identify conflicting requirements –Prioritise different options (if possible) –Planning of schedules and milestones –MaPMT plans and schedule o Hope for lots of fruitful discussions

3 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim MaPMTs for LHCb RICH o Multianode Photo Multiplier Tubes –Single photo tube containing 8x8 array of 64 dynode chains 2.1 mm pixel size, 0.2 mm gap –Bialkali photo cathode, UV glass window QE = 22 % at = 380 nm o Lenses –with one flat and one curved surface –Increases active area fraction to 85% –effective pixel size 3.0 mm o Readout Electronics –ASIC preamplifier chip with pipeline –Readout architecture L0 & L1 o Mechanics –Photo detector mounts & motherboard –Magnetic field shielding, mu-metal

4 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim MaPMT/Beetle Project o MaPMT R M64 with 8 dynode stages –gain:50000HV 800 V o Front-End electronics –Beetle1.2 chip –single photon equivalent 60 mV(2 mip) –signal / noise ratio40 –analogue or binary readout mode o MaPMT R M64 with 12 dynode stages –gain: 300’000 HV 800 V –Beetle1.2-MaPMT chip with gain adaption –single photon equivalent 30 mV(2 mip) –signal / noise ratio40 –analogue or binary readout mode

5 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim MaPMT Plans & Schedule o Read out the 8 dynode stage MaPMT –with Beetle1.2 in analogue and binary mode –using the Heidelberg board restricted to 12 channels Jan - June 03 o Read out the 12 dynode stage MaPMT –with Beetle1.2MA0 in analogue and binary mode –using the Heidelberg board, restricted to 12 channels April - June 03 o Read out all 64 channels of one or more MaPMTs –with the Beetle1.2/Beetle-MA0 in analogue and binary mode –with Beetle PCBoard July 03 - o Testbeam –Prepare and operate a cluster of MaPMTs in a testbeam, read out with the Beetle1.2 or Beetle-MA0 chip May - Sep 03

6 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Electronic Cost Comparison o Main Inputs –232 modules with 16 MaPMTs, 8 Beetle chips, 1024 channels –220 SFr/optical link, 190 SFr/ 4 copper links 5kSFr/ L1 board o Binary Electronics –232 optical links, 30 L1 boards1250 kSFr o Analogue Electronics –4x1856 copper links, 116 L1 boards2100 kSFr –TDR cost for comparison1600 kSFr –difference to binary 850 kSFr o Digital Electronics –1856 optical links, 78 L1 boards1970 kSFr –difference to binary 720 kSFr –Cost differences are understood –data links costs are rather robust O(  50 kSFr) –optimisation for L1 board necessary O(  100 kSFr) –absolute cost of L0 electronics needs to be reassessed

7 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Major Issues o MaPMT/Beetle studies –BoardBeetleJuly 03 –Testbeam13 Aug - 9 Sep o MaPMT type decision –8 vs 12 dynode stagesSep 03 o Binary vs analogue/digital readout –cost versus risks (common mode, comparator) –only decision possible now is analogue or digital –proposal -analogue or digital as baselineJune 03 o Design of L0 motherboard –includes cooling, on critical path Jan 04 –report from meeting at CERN o Software –Performance studies, robustnessSep 03

8 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Overall Schedule o 1 year old, –produced for June 2002 review, need to update o July 2002Resume design of Beetle chip done o Oct 2002Resume Motherboard design starting now o 1 Mar 2003Choose MaPMTs o Mar 2003Start tendering not started o 1 Oct 2003Place MaPMT Order o Jan 2004L0 F/E Electronics and Motherboard (MB) design completed o Mar 2004Start Photodetector testing o July % of MaPMTs delivered o Jan 2005L0 - F/E Electronics and MB R&D completed o Mar % of MaPMTs delivered and tested o Mar % production and testing of L0 and L1 units o June % of photodetector modules assembled

9 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Status of MaPMT Project o Large effort has started for MaPMT project in 2003 –Measurements of 8-dynode stage MaPMTs signal shape with Beetle1.2 has highest priority –Measurements with Beetle1.2MA0 are promising o More effort is needed –Need to catch up delays, 7 months for L0 Motherboard o MaPMT is baseline –More effort available –Need to re-think organisation of MaPMT project now –Many important decisions need to be taken soon

10 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Backup Slides

11 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Multianode Photo Multiplier MaPMT o Single photo tube containing 8x8 array of 64 dynode chains 2.1 mm pixel size, 0.2 mm gap o Gain: at 800 V o Bialkali photo cathode, QE = 22 % at = 380 nm o UV glass window, was borosilicate,  QE dE increased by 50 % Wavelength [nm] QE [%]

12 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Quartz Lenses o MAPMT active area fraction: 38% (includes pixel gap) o Increase with quartz lens with one flat and one curved surface to 85% o effective pixel size 3.0 mm 400 mrad 0 mrad no lenslens Demagnification (f -d)/f  2/3

13 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim 3x3 MaPMT Cluster Test o Measurements with –MaPMT: HV = -1000V o Data –subtract cross-talk and common-mode –Fit # of photo electrons per event: o Cherenkov ring, 6000 events o Observe in data background n pe = 6.96  p.e. o Expect from simulation n pe = 6.49  0.17 Single channel spectrum

14 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Electronics Costs Electronics Costs o Major cost differences in –data links –L1 boards o L0 Electronics –232 modules –16 MaPMTs, 1024 channels, 8 Beetle chips –4 data links per beetle, 128: 4 multiplexing, 40 MHz clock –cost very similar for all options o Binary Electronics –optical links to L1 board –32 : 1 multiplexing (1bit per data link) –232 optical links, 1 per module (was 2) –costs from John Bibby –cost per optical link 220 SFr, total 50 kSFr –30 L1 boards, 5 kSFr/board, total 150 kSFr –L1 costs reduced by 300 kSFr wrt to TDR

15 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Analogue/Digital Electronics Analogue/Digital Electronics o Analogue Electronics –similar to VELO, with copper links over 60 m –link costs include driver, differential link receiver and ADC(costs from Thomas Ruf) –4 x 1856 links, 190 SFr / 4 links, total data links 350 kSFr –L1 board input: 64 links = 16 cables –116 L1 boards, 5 kSFr/board, total L1 boards 580 kSFr o Analogue/Digital Electronics –similar to Inner Tracker, ADC at outer detector rim –need rad tolerant ADC (15kRad), –costs from Achim Vollhardt –4:1 multiplexing with 8bit ADC –1856 optical links, 252 SFr/link, total data links 470 kSFr –L1 board, input 96 optical links = 6 ribbons –78 L1 boards, 5 kSFr/board, total L1 boards 390 kSFr

16 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Comparator Review o Phone Meeting of Beetle Users –30 April 03 –comparing of notes –digital switching noise, 80 MHz, on analogue lines o Comparator Discussion –closed loop of understanding –small differences resolved –conclusions remain the same –3bits are marginal, –5bits has comfortable margin o Comparator in Beetle1.2 –3 bits, no access to negative offsets o Comparator in Beetle1.3 –5 bits, different sign for Offset and Delta IDAC –will be submitted in June

17 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim Allocation of Personnel o Agreed at RICH group leader’s meetingCERN, 26 Feb 03 o Immediate personnel requirements –Setup of read-out and testing A) and B)Edinburgh –Testing of BeetleMA0 B)Oxford –Production of PCBoard for C)Imperial College –Consulting for A) B) SW,JB,NS,DP –Procurement strategyok –Design of L0 motherboardCambridge, Oxford Genova –CoordinationFM o Additional personnel required in May –Cooling strategyGenova –Higher channel occupancyCERN, Edinburgh –Bleeder board for test beamCambridge –jigsUK/CERN –moulded lenses Genova

18 MaPMT Workshop, Imperial College, 26/27 June 2003 F. Muheim To Do List (on 28 April) o Read-out of 8-dynode MaPMT with Beetle1.2 –(re-)connect MaPMT done –measure analogue spectra with LEDdone –take data in binary modeJuly o Review of electronics cost –binary vs analogue vs digital read-outdone o Comparator review done o Decision on binary vs analogue –cost versus risks (common mode) ??? o Read-out of 12-dynode MaPMT with Beetle1.2 –testing of Beetle1.2MA0done –measure with LED analogue spectra done –take data in binary modeJuly