1. CLAS12 Central Detector Meeting, Saclay, 3 Dec 09Irakli.MANDJAVIDZE@cea.fr MVT Read-Out Architecture & MVT / SVT Integration Issues Irakli MANDJAVIDZE DAPNIA, CEA Saclay, 91191 Gif-sur-Yvette, France

2. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 092 Overview MVT Readout → Number of Channels → Architectural considerations → Front End Unit → Back End Unit → Data Rate Estimations SVT / MVT Integration → Number of SVT and MVT Channels → Some comparisons → Specific and common readout parts

3. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 093 Number of MVT Channels Number of MMs → Barrel X: 3 views x 3 MMs = 9 → Barrel Y: 3 views x 3 MMs = 9 → Forward: 3 stations x 2 views x 6 MMs = 36 → Total: 54 Number of channels → Barrel X: ~10 000 → Barrel Y: ~11 000 → Forward: ~25 000 → Total: ~46 000

4. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 094 MVT Read-out Architectural Considerations Minimal number of different hardware to develop and maintain → front end cards → back end concentrator cards Partitioning: DAQ Read-out Unit = View → Single communication channel with DAQ per View → Concentrate data from all MM in a View before sending to DAQ

5. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 095 MVT Read-out Architectural Considerations A DAQ Readout Unit One read-out unit per view FE links (FEL) FE Units (FEU) Readout Links (ROL) FEU...... BEU (control, concentration) Trigger Link (?) ← Clock ← Trigger ← Fast commands → Fast status DAQ Link (Ethernet) → Data ↔ Slow Control Bi-dir Optical Fiber ← Clock ← Trigger → Data ↔ Control / status FLEX cable → Signals FEU...... FEU (shaping, AD conversion, compression)...... Back End Units (BEU) Off-detectorCounting RoomOn-detector

6. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 096 MVT Read-out Architectural Considerations: Partitioning 12 MVT partitions 1X1Y2X2Y3X3Y1V1W2V2W3V3W Trigger / DAQ BARRELBARREL FORWARDFORWARD

7. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 097 Read-out Architecture Considerations: Front End Unit (FEU) 8- (4-) channel FADC Ctrl FPGA E/O Tx/Rx 64-Channel connectors 64 (128)-cannel ASICs 64 channels per FLEX 64- or 128-channel FE ASIC FEU6 option: → 6 64-channel FLEXes → 384 channels → 6 or 3 ASICs → an 8- or 4-channel FADC → a controller FPGA → an optical link towards a concentrator card

8. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 098 Read-out Architecture Considerations: FE Granularity Barrel X with 3 MM / view → D1X: 6 FEU (2 FEU / MM) → D2X: 9 FEU (3 FEU / MM) → D3X:12 FEU (4 FEU / MM) Barrel Y with 3 MM / view → D1Y: 6 FEU (2 FEU / MM) → D2Y: 9 FEU (3 FEU / MM) → D3Y:12 FEU (4 FEU / MM) Forward with 6 MM / view → Disk:12 FEU (2 FEU / MM) Total number of FEUs: 126 → 756 64-channel ASICs or 378 128-channel ASICs → 756 64-channel FLEXes

9. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 099 Read-out Granularity: Back End Unit (BEU) Functionality → Receives CLAS12 clock, trigger and control flow & distributes it to all FEUs of a view → Concentrates data from the FEUs & sends them to DAQ BEU12 option: → 12 optical FEU links → Ethernet DAQ – Slow Control link → Trigger – Clock – Fast Control link whatever standard → Form factor? Total of 12 BEUs needed BEU Ethernet DAQ Slow Control link Trigger Clock Fast Control link

10. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0910 Read-out Granularity: Barrel X,Y and Forward V, W Units FEU BEUBEU BEUBEU BEUBEU B1X, B1YB2X, B2YB3X, B3Y BEUBEU F1V, F2V, F3V F1W, F2W, F3W MM1MM1 MM2MM2 MM3MM3 MM1MM1 MM2MM2 MM3MM3 MM1MM1 MM2MM2 MM3MM3 MM1MM1 MM3MM3 MM5MM5 MM2MM2 MM4MM4 MM6MM6

11. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0911 Data Rate Estimations Hypothesis → 10 MHz Barrel background (safety factor ~2) → 20 MHz Forward background (safety factor ~1.4) → 20 kHz L1 rate (safety factor 2) → Multiplicity: barrel 4, forward 1.2 → 20 MHz sampling rate → 4 samples / channel read-out Full readout: 7400 Mbyte/s → Event size 380 Kbyte Zero suppression: 75 Mbyte/s → Subtract common noise, apply threshold → Event size 3.8 Kbyte Data reduction factor of ~100

12. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0912 Number of SVT Channels Speculations 3 Regions → 2 views per region Regions composed of 256-channel modules → Region 1: 8 modules → Region 2: 12 modules → Region 3: 16 modules Number of channels → Region 1: 4096 → Region 2: 6144 → Region 3: 8192 → Total: ~18 000 ~140 additional 128-channel ASICs

13. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0913 Current Ideas: SVT On-detector front-end electronics → relatively stringent space & power constraints Space → ASIC wire-bonded minimal number of external components → as complete read-out system as possible higher channel count → cooling extends up to detector Power → minimize mW / channel ratio → special attention to low voltage distribution

14. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0914 Current Ideas: MVT Off-detector front-end electronics → looser space & power constraints Space → ASIC packaged more complex read-out circuitry possible → external digitization, zero suppression lower channel count → cooling system does not extend to detector Power → can permit somewhat higher mW / channel ratio → low voltage is not distributed to detector

15. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0915 Common Readout FLEX MVT FEU...... CONNECT PROTECTPROTECT ASIC ADC FPGAE/O MM ASIC ADC FPGAE/O SVT module (double layer) Common Readout Controller (CROC) On-detectorOff-detectorCounting Room LVDS ROL Optical link CROC Readout Link (ROL) An external FADC: additional 1 mW / channel (at least) Trigger Fast control Data Slow control Trigger Fast control Data Slow control Backend Unit

16. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0916 Data Rate Estimations: SVT Speculations Hypothesis → 30 MHz background (safety factor ~?) → 20 kHz L1 rate (safety factor 2) → Multiplicity: 1.2 (?) → 20 MHz sampling rate → 4 samples / channel read-out Full readout: 2800 Mbyte/s → Event size 144 Kbyte Zero suppression: 19 Mbyte/s → Subtract common noise, apply threshold → Event size 1 Kbyte Data reduction factor > 100

17. Irakli.MANDJAVIDZE@cea.frCLAS12 Central Detector Meeting, Saclay, 3 Dec 0917 Discussions MVT participation in L1 Trigger is not envisaged What is the control interface? → clock and trigger distribution Current FE electronics volume estimates: 0.12 m 3 → a cube of 50 cm! → central SVT / MVT Tracker – 0.1 m 3 What are the space constraints? → how do the SVT and MVT on-detector infrastructures cohabitate? → how do they cohabitate with other central detectors? power, cables, channel protections, electronics, cooling What can be common? → ASIC? → read-out controller & back-end concentrator? What if the SVT electronics could be off-detector? The most optimal read-out granularity and partitioning will be defined accordingly