Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 1 XFEL-PIXEL Readout and control Detector requirements/proposal Basic concepts for experiments Control electronics Selecting/rejecting bunches Backend-systems Time schedule Conclusion

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 2 Detector requirements Call for experiments: large pixel detectors:> 1Mega-Pixel large number of frames:XFEL: bunches/sec large dynamic range Photons/pixel/frame distinguish0 and 1 Photon, rest Poisson-limit With 2Bytes/pixel and 1MPixel60GByte/sec -but experiments will not handle frame rate -Data reduction of "compression" is not effective: Statements of nearly nothing to factor 2-4.

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 3 Three Proposals AP-HPAD: analogue pipe-line Hybrid Array Pixel Detector Si-pixel: ASIC stores signal while bunch train into capacitors digitization/data-transfer in pause between trains 400 frames/train LSDD: Linear silicon drift detector One dimension is coded into drift-time: 200MS/s while train data transfer in pause between trains. 600 frames/train LPD :Large Pixel Detector analogue pipeline while train digitization between trains 512 (256) frames/train Þ All extendable beyond 1Mpixel All around every 5-10 bunch All might run in parallel

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 4 Idea: Basic setup of all experiments Specific to experiment, here AP_HPAD Generic for all experiments

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 5 Idea: Concept for control electronics General task: - Boot - Collect information - Synchronize to XFEL clocks, time - Synchronize Interface electronics Backend Experimental area - Generate/distribute Clocks/data - User interface - Write to backend Monitoring/Status - Usage at other laboratories

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 6 Selecting/rejecting bunches Aim: - Best use of limited pipeline in detector-head - Limit resources for backend Staged concept: - Store predefined bunches into pipeline of experiment - Fast reject (before next bunch): hardware detector, Slow reject: After bunch train Handle slower information, information from XFEL - Transfer to backend-system More fancy selection in CPU-farm Rates: hard to guess, input from science needed - gas stream through X-ray-beam: - solid targets in beam (just first bunch) - that is not all. Who needs what?/how much?

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 7 Idea: Data stream to and concept of backend-system Aim: - Collect complete frames into one CPU - Data in mass storage sorted for "Offline"-analysis Allowance: - Calculation on frames before sending to mass storage - Decisions on frame to store/reject inside backend system. - Rejecting frames on more fancy information from external signals. - Write data frame-wise to mass storage - easier offline.

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 8 Interface: Experiments to backend-system Rough: Data from Pixels written to RAM and read in other sequence By that: One group of frames transfers to 1 Link to BE. Still 8 or more of such modules transfer to same backend-system

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 9 Need, controlled time sequence: So that each CPU gets data from all interface-modules without time conflict

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 10 Idea: Concept of backend-system SwitchCPU-Farm Interface electronics Stage 1: » 100 Links/1Gbit/s mass storage control electronics Feedback monitoring data XFEL-accel.?

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 11 Rates: - Not well defined, what does which of experiment - AP-HPAD: 2Bytes/pixel/frame is reasonable - LSDD: Start with over sampling: Where to reduce to what, has to be a common diccussion - LPD: Rate expected to be similar to AP-HPAD, but I haven't seen their proposal. - First tests of compressions had been not effective Recent statement for single case was factor 2-4. Estimate to storage: 1Mpixel * 500bunches/train * 2Bytes/pixel * 10trains/s 10GBytes/sec Discussion with inputs from backend/science needed to settle rates/uptime/technical-effort/offline-effort

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 12 Time schedule 2007: Experiments write proposal 15-April 2007 end : Designing, Constructing, but also Laboratory tests and usage at other beam lines 2009(?) DAQ needed for tests - no large CPU-farm LCLS has 120Hz and not 30000bunches/sec 2013: 1Mpixel dedectors at XFEL3*(10-20GB)/sec 20xx: Upgrades beyond 1MPixel (e.g. 4Mpixel)

Peter Göttlicher, DESY-FEB, XFEL-DAQ-2007/03/05 13 Conclusion Concept is there, open to change and do an other way Two aspects: Control electronics Backend-system Ideas about numbers, but a lot of open questions Discussions needed with input for - effort in backend - science requirements - offline possibilities - feasibility of interface-electronics Common effort for all experiments is a strong wish