1. SuperB igbite Spectrometer in Hall A Background: photon (250-500 MHz/cm 2 ) charged (160-200 kHz/cm 2 ) 1 Large luminosity Moderate acceptance Forward angles Reconfigurable detectors Large luminosity Moderate acceptance Forward angles Reconfigurable detectors Front tracker reused in BigBite Physics: Nucleon Form Factors SIDIS – TMD’s... Nucleon structure

2. Silicon Detectors 2

3. 3

5. 5

6. 6

7. 7

9. GEM 9

10. Main Technical solutions 40x50 cm 2 module Front Tracker Chamber: 40x150 cm 2  Use the COMPASS approach: 3xGEM, 2D readout - one significant difference: use new single mask GEM foil (instead of double mask) – cheaper and faster production  Modular design: chambers consists of 3 independent GEM modules (40x50 cm 2 ) with thin dead area  Electronics around the module, direct connection; 90 degree bending between modules  External support frame in carbon fiber (long bars) to minimize thermal deformation 10

11. Gluing Finalization (solder resistor, check HV) Stretching Electronics integration Test and characterization by rad. source and cosmics Permaglas Frames Visual Inspection Ultrasound bath cleaning GEM Foils HV curing and quality test Put together (align on reference pins) Glue Curing (>24 h) Assembling gas lines Electronics Test 11 Clean room Module production fully established in INFN-Catania Electronics preliminary QA in Genoa Module integration and characterization in INFN-Sanità GEM Module construction process Production rate 2 module in 3 months

12. SBS GEM Tracker - Test Beam / Jan 2014 Reference Small GEM 3 Big GEMs DESY/EUDET Pixel Telescope Small scale final system (gas, LV, HV monitored) Main Goals: Characterize chambers in terms of charge sharing, efficiency and spatial resolution at different HV, gas mixture. Figure out the gain variation of the previous test → Got lot's of good data with high spatial resolution information from pixel telescope → Stable performance (“all” conditions carefully monitored) 1-4 GeV Electron Beam 12 AIDA-EUDET support

13. 13

14. GEM Production and Test Status Produced or Assembled TestedNOT AcceptedDegradation after first test GEM foils51257 Readout+Honeycomb15 / 1871 GEM Module5+302 Front End Electronics250*502- VME Modules265+0- Backplane8012+ Patch Panel50many returned to company*** 14 The very first 4 GEM foils did not pass the original quality checks, 3 recent GEM foils of the same bunch did not pass the quality check One readout + honeycomb suffered bad gluing (probably still usable) 2 of the GEM modules passed preliminary tests but then degraded significiantly (large dark current due to (? gas contamination ?); still chance to fix them. *** soldering problem, bug fixed

15. 2009201020112012201320142015 Preliminary design (include MC study) Prototyping Procurement Pre-Production (1 st chamber) Production Beam Test Dec DESY Sept Mainz June CERN May DESY Jan DESY 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM15 Development phases in part affected by constraints in the flow of funding Delivery delay of the GEM foils from CERN for prototyping and pre-production (no significant impact in SBS, we started erlier) During pre-production we made some fine optimization: GEM foil, details in construction procedure; one drastic change in foil quality check. Development includes: GEM chambers, readout electronics (and related software) Schedule and Status

16. 16 S ij – neuron (0 or 1) – connection between two points Residues Kalman Filter Reconstruction: simulation Track Association by NN / Simulation Energy Vi j Neuron changing rate

17. GEM Tracker Activity 2014-2015 Continue Production Test, Characterization and Calibration of GEM and electronics Fix damaged modules/material, replace if no fix possible Finalization of a rubust and efficient track reconstruction algorithm Complete and test the complex firmware of the DAQ Study (and solve) open issues 17

18. Electronic (GEM + Silicon detector) 18

19. Revised memory mapping D64 read only cycle implemented: MBLT, 2eVME, 2eSST 2eSST simulated peak speed: 148, 222, 296 MB/s Event builder implemented and simulated TBD Multiboard block transfer Analyze use of fiber optic protocol Electronic Status MPD v 4.0 firmware update MPD v 4.0 VME interface testing 2eSST cycles tested with STRUCK SIS-3104 2eSST supported by new firmware release Readout speed measured by software: 100 transfer 4MB each. Data integrity checked for each block. Speed limited by SIS3104 2Gb/s fiber connection Bus speed is measured directly on VME bus Implemented multi event block structure as suggested by DAQ people. Native data width: 24 bit, packed to 32 bit on 64 bit boundary for efficiency. Implemented 128MB FIFO data buffer using DDR2 SDRAM. Quite complicate machinery used to arbiter read and write to/from DDR2. Output can be read in 32/64 bit format in any of the supported VME cycles, including 2eSST. Performed functional simulation (FPGA + DDR2 + ADC) of quite simple events to follow all the signals. Some effort has to be put in DAQ driver to recover packed data. Event Builder

20. 20 Analyze a possible implementation of fiber optic data link to be connected to the SSP Implement Multi Board block transfer (some hints needed) Deep debug and test (implies rewriting of some DAQ code) Electronic Activity 2014-2015

21. HCAL 21

22. Hcal 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 22 Italian activity

23. 23

24. 24

25. HCAL 2014-2015 activity 25

26. Analysis 26

27. 9 Be(e,e’K) 9 Li  (G.M. Urciuoli et al. Submitted to PHYS REV C) Experimental excitation energy vs Monte Carlo Data (red curve) and vs Monte Carlo data with radiative Effects “turned off” (blue curve) Radiative corrected experimental excitation energy vs theoretical data (thin green curve). Thick curve: four gaussian fits of the radiative corrected data An elementary model for the (e,e′K+) reaction with a di ff erent balance of spin-flip and non-spin-flip amplitudes might help to resolve the disagreement with theory of the relative strenght of the peaks in the doublets

28. 28 Experiment E07-002 Present result for K LL in E07-002 seems to confirm previous measurement of E99-114, at a different angle. Work in progress. Study of systematic uncertainties is undergoing. Optimize analysis in order to conclude that at our energy regime, pQCD predictions are excluded. With those points included, ready for publication

29. 29 Studies on 3He as neutron effective target in SIDIS

31. Support Slides

32. Workforce and funding *) one mechanical engineer **) electronic engineer INFN/Funding: Prototyping and Production (2008-2014): 800 kUSD Production and Maintainance (2015-2017): ~50 kUSD/year INFN Group Researcher (Unit / FTE) Tech. (Unit / FTE)Role Bari2 / 0.5Gas system and beam test Catania3* / 1.53 / 2GEM module assembling, mechanics, beam test, analysis Genova1** / 0.5Electronics design and test Rome/Sanità1 / 0.53 / 2Coordination, design, test, chamber integration, analysis, DAQ and reconstruction Total7 / 3.06 / 4 Other support: CERN / UVa / JLab 32

33. Assembling Improvements in Catania Several small but effective impromevents during last 2 years; one of the most relevent is the compression system during glue curing --- From Lead to vacuum --- 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 33 Old System based on Lead Bricks Current System based on vacuum bag Very uniform pressure for glue degassing Original idea from LNF- Bencivenni Group

34. Test and characterization setup Almost finalized Use small 10x10 GEM as «reference» (in series) Large scintillation pads for cosmic Test up to 3 large GEM simultaneously 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 34

35. HV divider and new GEM foils 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 35 Protective SMD resistors HV connector«spike» signal output HV Divider and spike monitor circuit Reasonably compact, Easy to change Include output signal for «spike» detection

36. Spacers shadow Spacer shadow of ≈ 2 mm → 2.2% of total dead area of a single GEM module (Cluster finding not optimized for spacer border) 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 36 Masked channels Spacer Cluster distributions of 9 cumulated runs

37. Simulated Start Time Reconstruction 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 37 Reconstructed Start Time (t0) Error on t0 Chi2 of the fit Zoom Use double exponential function to fit 6 samples extracted with uniform random jitter (±12.5 ns) and poissonian amplitude distribution + gaussian noise. Optimal latency setting: first sample around the beginning of the signal

38. 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 38 GEM Beam Test: Spatial Scan – Start Time Start time increase slightly (but within uncertienties) Start time basically constant or sligtly decreasing (opposite to y ?)

39. 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 39 GEM Test Beam: spatial uniformity – Hit Cahrge

40. Background level of: –400 MHz/cm2 photons –200 kHz/cm2 charged Signal width ≈ 250 ns → Hits/cm2/trigger ≈ 0.1 → Ghosts/cm2/trigger ≈ 10-20 ! 7 July 2014 - JLab SBS Coll. Meeting - Front Tracker GEM 40 Three steps track reconstruction: Suppress accidentals and ghost with time and charge correlation Associate hits with global analysis (neural network approach) Precise track reconstruction on remaining candidate tracks by Kalman filter method

41. 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM41 “Residual Noise” on first APV channels Pedestal RMS of Pedestal Card + Flat Adapter Condition: 4 cards connected to chamber (one by flat adapter) Cards connected to VME by 20 m long HDMI cables Evident noise on first few (up to 8) channels of each card; This noise is somehow masked in the card with adapter (this is way we never put great attention to it in the past) Baseline noise at the level of 7 ADC channel. VME GEM HDMI cable MPD Strips, physics order

42. 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM42 Electronics Misconfiguration Issue Small current drop during APV configuration; the “normal” level must restore In case of proper configuration; otherwise the electronics does not work properly Chamber appears inefficient → this likely explain the gain issue in 2013 DESY test Electronics Low Voltage monitor 2 power lines for 2 groups of cards

43. BARI Gas System w/Humidity Sensor and Absorber 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM43 or GEM_50x40 Series operation ~ 20 m long pipe ~10 m or GEM_50x40 Series operation ~10 m < 100 ppM of H 2 O

44. GEM Test Beam: spatial uniformity – Charge Sharing Charge asymmetry = 2 (Cx-Cy)/(Cx+Cy) ≈ 0.4÷0.5 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM y x HV=4100 Ar/CO2=70/30 → x/y Charge Sharing ≈ 1.5-1.6 Charge asymmetry spread ≈ 0.3 NOTE: some x/y hits can be not correcly associated or have pileup due to events with 2 or 3 particles/pulse

45. Reconstruction Efficiency vs #Event 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM45 Efficiency holes in some of the runs: beam instability ? Lost synch with trigger ? Good run Analysis work in progress, recently master student from Catania joint. Several data to be analyzed

46. SBS GEM Test: typical event (single module) y - Strip x - Strip T0 (A 0 ) T0+125ns T0+25ns (A 1 ) Combination of T0, T0+25ns, T0+50 ns Fit of hit signal evolution cluster Readout dual layer (x bottom and y top) strip plane T0+50ns (A 2 )

47. x y x/y cluster charge max strip charge beam position cluster width max peak sample # clusters SBS GEM Test: measured quantities (run 499) Note: beam cross-section ≈ 3x2 mm 2, approx. 30% with 2 or 3 hits in beam pulse

48. x y x/y IntegralStart time (t0)Leading Const.Trailing Const.Chi 2 SBS GEM Test: signal evolution fit (run 499) 6 sample fit! tau0 ≈ 20 ns, tau1 ≈ 90 ns, RMS(t0) ≈ 4-5 ns

49. Time spread < 5 ns! GEM Beam Test / Time resolution Excellent (surprising ?) start time spread (from fit) < 5 ns expected at the level of 25/sqrt(12) ≈ 4 ns (in case of negligible contribution from electron drifting in GEM) x/y start time reasonably correlated no apparent effect of MPD clock synch time spread depends on choice of APV latency (see next slide) Test beam pulse period 160 ms, multiple of APV clock period

50. GEM Beam Test: Spatial Scan – Start Time Gas flow rate: 54.3 ccm (0.5V/h) Peak Sample Start Time (fit) Look reasonably consistent Peak Sample vs V/h: 2 V/h: 1.2 ±0.4 1 V/h: 1.2 ±0.4 0.5 V/h: 1.3 ±0.5

51. Working Space @Jlab needed GEM chamber assembling and testing need space at JLab (layout sent in 2010) 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM51

52. Main Open Issues 1.Long cable noise If no fix available: change cabling topology 2.Readout plane manufacturing Test in high bck needed ! 3.GEM modules «aging» To be investigated 4.Data rate / VME Crates (?) Implement optical fiber and SSP communication (?) 7 July 2014 - JLabSBS Coll. Meeting - Front Tracker GEM52

53. GEM Electronic System Status Production status of electronic boards Firmware Update on MPD v 4.0 VME intrerface Event Builder Paolo Musico and Evaristo Cisbani 7-8 July 2014SBS Meeting @ JLAB53

54. Material Procurement Status Front TrackerModuleChamberFront TrackerIn houseOrdered Chamber16 Module13183 GEM Foils (CERN) Drift Foil1318 GEM foils395451 Readout131815 Honeycomb1318 Mechanics (RESARM) Frame 0 – Cover131820 Frame 1 – Top131820 Frame 2 – Drift131820 Frame 3 – GEM263640 Frame 4 – Readout131820 External Frame (Plyform)161* Electronics (EES) FE1854324250100 MPD42426 Backplane4127280 Patch Panel (digital + analog)84850 Electronics Cabling (LINDY) HDMI 3m cable82414480 HDMI 20m cable5159045 LV cable41272** HV cable721126** HV Divider131840 LV Power Supply (6Vx20 Amp)168 HV Power Supply131824 Gas System Controller + Flowmeters (MKS)11 Connectors (Legris)1036212250 Patch Panel Gas164 General Patch Panel12 Most of the material already in house or procured Remaining parts will be procured in 2014 Assembling line operational Testing line under finalization *) Design completed, waiting first proto **) 2014 funding 54

55. Production Status SBS Meeting @ JLAB557-8 July 2014 APV Front-End cards 210 delivered (some used for DESY test) 140 in progress (SMD ok, to be bonded) Backplanes 74 delivered (some tested) MPD 28 delivered and tested: 2 with marginal problems (to be fixed) Patch Panels 25 Analog Patch Panels delivered 35 Digital Patch Panels delivered

56. SBS Meeting @ JLAB567-8 July 2014 CYCLEDATA periodBus SpeedReadout Speed 2eSST1606 ck = 54 ns (3s/3h) 142 MB/s117 MB/s 2eSST2674 ck = 36 ns (2s/2h) 213 MB/s124 MB/s 2eSST3203 ck = 27 ns (2s/1h) 284 MB/s124 MB/s