PANDA EMC Trigger and Data Acquisition Development Experimental Physics Center Institute of High Energy Physics Beijing II. Physics Institute Justus-Liebig-University Giessen Qiang Wang December 7th, 2009 XXXI PANDA Collaboration Meeting

Outline Motivation PANDA physics programs EMC Introduction Simulation EMC Readout Electronics Introduction EMC DAQ schematics Algorithms development Future work

Motivation The Compute Node V2 is ready for use, lots of simulation results on EMC are also available now, so it is the time for algorithms development; Without real algorithms running on The Compute Node, we can not sure if it is powerful enough (new ideas come from application); Software Plug-in module PC

PANDA physics maps (3) Charmonium hybrids (1) Charmonium channel 1 Background Background >>not to loss photons (low Eth, Bump splitting) (2) Charmonium channel 2 (4) Measurement of the time-like EM form factors of the proton Background Angular distribution a suppression better than 108 >> efficient and clean electron identification and accurate measurement of the final state photons originated from decay

Interaction of Particles with Different Detectors Calorimeter: Charged particle: leptons( ), mesons( ) and baryon( ) Neutral particle: photons

Requirements Accurate energy and spatial resolution of reconstructed photon; Good electron/hadron (shape parameters) and electron/photon separation (correlation with Track Detector ); Events channels have similar final state particles compared with background events, no direct trigger criteria. But some physics parameters need to be calculated on DAQ stage (e.g. Cluster Etot, Gravity center position, Shape parameters of cluster) and events selection should be done with the correlation of additional sub-detectors information.

PANDA Detector Forward endcup Barrel EMC Employ PWOII Crystal

EMC geometry 3600 11360 592

Energy range Vs spatial resolution requirements backward endcap EMC: 10(20) MeV- 0.7 GeV; barrel EMC: 10(20) MeV- 7.3 GeV; forward endcap EMC: 10(20) MeV- 14.6 GeV; Forward endcup From PROTO60 results Barrel EMC Backward endcup To identify overlapping photons (from Pi0 decay with small opening angles), it is mandatory to efficiently split cluster into individual photons which requires the central hits of the involved photons are separated by two crystals. Backward endcap: 10° Barrel EMC:2° Forward endcap: 1°

Simulation Events GeV Energy Range: 1~2GeV

Simulation Events GeV Energy Range: 1~2GeV

Simulation Events GeV Energy Range: 1~2GeV Bump overlapping when Pi0 decay to 2 Gamma Energy Range: 1~2GeV

PROTO60 results on cluster size For E=1.414GeV photon, most of the energy deposits in a 5*5 crystals array, about 80% energy deposited in central crystal

Hit Rates and Absorbed Energy Dose in Single Crystals Figure 1: Hit rate in the barrel part from the DPM background generator at pp=14 GeV/c. 60KHz Figure 2: Integrated single crystal rate for the barrel section for an energy threshold of E>3MeV using DPM at 15 GeV/c incident beam momentum. Figure 3: Integrated single crystal rate for the forward endcap for an energy threshold of E>3MeV using DPM at 15 GeV/c incident beam momentum.

ADC Module (PANDA_EMC_Tdr P.98) Main Feature: 40~80 MHz ADCs; 2 overlapping 12bits ADC to provide dynamic range of 12000; One ADC module provide 120 channels Barrel EMC needs 4*11360 channels[2(Range overlapping)*2(APD)] Functions: time adjustment and distribution of the global clock signal; noise calibration; common mode noise suppression; pedestal subtraction; autonomous hit detection; conversion of ADC data and linearization of the full data range; transporting the hit information together with the time stamp to the data multiplexer; slow control

Data Multiplexer (PANDA_EMC_Tdr P.99) Interfaces: 1 bidirectional 1 Gbit/s optical link to/from the Time Distribution System; 10 bidirectional 1 Gbit/s optical links to/from the front-end electronics (the digitizer modules); 2 bidirectional 2 Gbit/s copper links to/from the backplane to the neighboring multiplexers; 2 bidirectional 2 Gbit/s links to the DAQ system; 1 Ethernet link to a general purpose network for configuration and slow control; 1Gb/s from/to Time Distribution System 2x2Gb/s Optical Link to DAQ Data Multiplexer 10x1Gb/s Ethernet Link Functions: The data multiplexer performs advanced data processing by extracting the signal amplitude and time; combining single hits into clusters, and sorting the clusters in a time-ordered sequence. 2x2Gb/s from/to backplane to neighbor Multiplexers

EMC Readout Electronics Introduction Assumptions: Run: 30 minutes ; Bust: 2uS with 500nS gap; +TDC information to separate events in the same Bust(20 bits needed with 25ps time resolution); Burst ID Bust1.Event1 Event i Bust2.Event1 Bust i TDC Info. Energy Crystal ID Bust1.Event N 40Events/Burst*540Byte/Event*~22kByte/Burst Total Data Rate:8.8GByte/s EventSize=90(Multiplicity)*(20bit(Time info)+14bit(ADC)+14bit(DetectorID))=540B ADC Module Data Multiplexer FEE FEE Read Out Module FEE FEE FEE 2X Optical Link FEE FEE 30 Crystal +60 APD 60 Pre. Amp. 120 Ch/Module 10X1Gb/s Up to 150 Crystal/Module for Low Hit Rate 60 Crystal/Module for High Hit Rate situation For range overlapping,2*ADC/Pre. Amp BarrelEMC:11360 Crystal Up to 5 ADC Mod/Data Multiplexer

Readout Schematic 1 Compute Compute Node Node Compute Compute Node First Stage Second Stage Read Out Module Compute Node Compute Node EMC info. Compute Node Compute Node Compute Node Read Out Module Compute Node Compute Node Compute Node Regional Data sent to Compute Node via different channels, Compute Node need to collect information belong to the same sub-event for high level processing Compute Node Compute Node Read Out Module Average 842Mbps/Module 76 Modules for Barrel EMC 19 Compute Node other detectors info. SODA SODA SODA Tasks 1. Signal Feature extraction (Time, Amplitude); 2. Data Zero compression (?); 1. Regional Clustering; 2. Correlation of regional information; 3. Cluster Properties extraction; 4. Pattern recognition; 1. Correlation; 2. Physical parameters calculation; 3. Event building; Read Out Module Ass.150 Crystal/Module 76 Modules for Barrel EMC is needed

Impact of region size on cluster finding efficiency Region i, j Region i+1, j Data Concentrated on one CN Phi*Theta: 10Cx*6Cx Phi*Theta: 20Cx*24Cx 80% need regional correlation 33% need regional correlation Simplified calculation: a 5*5 cluster distributed in the region Computing power of one FPGA also needs to be evaluated

Data Concentrator on One CN FPGA1 Agent1 Agent2 Agent3 Agent4 FPGA3 FPGA4 FPGA2 Switch FPGA0 Cross link of four FPGAs on the same board will be used; 2. An IP liked protocol for RocketIO based serial link is need to concentrate data automatically; 3. Concentration at shelf level is also possible;

Readout Schematic 2 Compute Compute Node Node Compute Compute Node Second Stage First Stage Read Out Module Compute Node Compute Node EMC info. Compute Node Compute Node Compute Node Read Out Module Compute Node Compute Node Compute Node Backplane Connection Backplane connection provide way to collect data belong to the same sub-event Compute Node Compute Node Read Out Module Other Detectors info. 150 Crystal/Module SODA SODA SODA 1. Signal Feature extraction (Time, Amplitude); 2. Data collection (?); 3. Data Zero compression (?); 1. Clustering; 2. Cluster Properties extraction; 3. Pattern recognition; 1. Correlation; 2. Physical parameters calculation; 3. Event building; Tasks

What need to be done on the First Stage Compute Node Compute Node EMC info. Full event info. Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Compute Node Other Detectors info. Event selection should be done by correlation with other sub-detectors Tasks( using Schematic1): Regional cluster finding; Correlation of regional information; Feature extraction (e.g. Etotal, Gravity Position, Cluster Size, Bump Overlapping detection); Clusters selection (e.g. Emax>Eth1, Etotal>Eth2……); Sub-event format for high level correlation;

Reco. Cluster Finder Algorithm For(i=0; i<nHits; i++) For(j=0; j<i; j++) { if(isNeighbor(a[i], a[j])) TagHits(a[i]); if(isInTwoCluster()) MergeTwoCluster(); else CreateNewCluster(); } Phi Theta Advantages Able to escape losing hits when Cluster have holes; No limitation for data transmitting order; Shortcomings Not a time-effective algorithm; Need large mount of memory to store intermediate results;

Seeds finding (Ehit>Eth2 or Neighbors of Ehit>Eth attaching Cluster Finder Algorithm (Preliminary) Hits:48 simple lineal map function Hits: Two dimension map hits filtering 6 Clusters left Seeds finding (Ehit>Eth2 or local Emax Finding) Neighbors of Ehit>Eth attaching Cal. Etot, ClusterSize, Gravity Position, ……

Future work Computing power of one FPGA needs to be evaluated with the algorithms( Cluster Finder, LinearPos, Esum); Serial transmission protocol for Data concentration needs to be considered; More simulation in PANDA Root framework and adaptive algorithm development;

Thanks !

Backup slides

Cluster Finder Algorithm from ALICE TCP Step 1: Simulation data read from .root files and reformed in predefined forms; Step 2: For data belong to the same event will be processed in column, neighbor hits in the same column will merged to as one strip; Step 3: Column based merge will be done, neighbor strips will be merged to one cluster; Step 4: Merged cluster above the Eth will be processed to get parameters like Total hits, Etot, Size, Gravity Position … … Phi Theta Advantages Processing data column by column, only the formal column data need to be stored; 2. Only need small RAM and FIFO, and fabric resources, algorithm is easy to be implemented in our platform; Shortcomings Data need to be transmitted in restrict spatial order; May lose hits when cluster have holes; Unable to do bump splitting;

Cluster Finder Algorithm(1) Calculation Results: |EventID:0 ||Entries:21 | |EventID:0 ||Time:19.833334 ||Row:22 ||Etot:0.008274 ||Y1:106 ||H1:1 ||PwPrdY:0.008274 ||Index:1 ||Appendix:0 | |EventID:0 ||Time:19.000000 ||Row:23 ||Etot:0.024766 ||Y1:145 ||H1:1 ||PwPrdY:0.024766 ||Index:2 ||Appendix:0 | |EventID:0 ||Time:16.100000 ||Row:28 ||Etot:0.074240 ||Y1:118 ||H1:1 ||PwPrdY:0.074240 ||Index:3 ||Appendix:0 | |EventID:0 ||Time:17.000000 ||Row:29 ||Etot:0.358428 ||Y1:117 ||H1:2 ||PwPrdY:0.608158 ||Index:4 ||Appendix:0 | |EventID:0 ||Time:17.000000 ||Row:30 ||Etot:0.129021 ||Y1:117 ||H1:3 ||PwPrdY:0.151940 ||Index:5 ||Appendix:0 | |EventID:0 ||Time:15.000000 ||Row:31 ||Etot:0.023883 ||Y1:116 ||H1:2 ||PwPrdY:0.042227 ||Index:6 ||Appendix:0 | |EventID:0 ||Time:16.833334 ||Row:37 ||Etot:0.009213 ||Y1:135 ||H1:1 ||PwPrdY:0.009213 ||Index:7 ||Appendix:0 | |EventID:0 ||Time:16.100000 ||Row:40 ||Etot:0.105600 ||Y1:126 ||H1:1 ||PwPrdY:0.105600 ||Index:8 ||Appendix:0 | |EventID:0 ||Time:19.000000 ||Row:41 ||Etot:0.014708 ||Y1:124 ||H1:1 ||PwPrdY:0.014708 ||Index:9 ||Appendix:0 | |EventID:0 ||Time:16.000000 ||Row:41 ||Etot:0.055819 ||Y1:126 ||H1:2 ||PwPrdY:0.073182 ||Index:10 ||Appendix:0 | |EventID:0 ||Time:16.833334 ||Row:41 ||Etot:0.007373 ||Y1:129 ||H1:1 ||PwPrdY:0.007373 ||Index:11 ||Appendix:0 | |EventID:0 ||Time:18.750000 ||Row:42 ||Etot:0.136021 ||Y1:125 ||H1:2 ||PwPrdY:0.232557 ||Index:12 ||Appendix:0 | |EventID:0 ||Time:12.000000 ||Row:43 ||Etot:0.203453 ||Y1:124 ||H1:4 ||PwPrdY:0.520251 ||Index:13 ||Appendix:0 | |EventID:0 ||Time:13.928572 ||Row:43 ||Etot:0.003663 ||Y1:130 ||H1:1 ||PwPrdY:0.003663 ||Index:14 ||Appendix:0 | |EventID:0 ||Time:12.000000 ||Row:44 ||Etot:0.048541 ||Y1:124 ||H1:3 ||PwPrdY:0.095294 ||Index:15 ||Appendix:0 | |EventID:0 ||Time:14.000000 ||Row:45 ||Etot:0.021971 ||Y1:125 ||H1:1 ||PwPrdY:0.021971 ||Index:16 ||Appendix:0 | |EventID:0 ||Time:25.166666 ||Row:45 ||Etot:0.006426 ||Y1:127 ||H1:1 ||PwPrdY:0.006426 ||Index:17 ||Appendix:0 | |EventID:0 ||Time:11.750000 ||Row:46 ||Etot:0.012057 ||Y1:122 ||H1:1 ||PwPrdY:0.012057 ||Index:18 ||Appendix:0 | |EventID:0 ||Time:20.000000 ||Row:46 ||Etot:0.020091 ||Y1:130 ||H1:1 ||PwPrdY:0.020091 ||Index:19 ||Appendix:0 | |EventID:0 ||Time:10.000000 ||Row:47 ||Etot:0.003657 ||Y1:131 ||H1:1 ||PwPrdY:0.003657 ||Index:20 ||Appendix:0 | |EventID:0 ||Time:14.000000 ||Row:50 ||Etot:0.007301 ||Y1:57 ||H1:1 ||PwPrdY:0.007301 ||Index:21 ||Appendix:0 | |EventID:0 || Time:19.000000 ||Hits:1 ||Etot:0.024766 ||LeftCx:23 TopCx:145 ||Width:1 Height:1 ||PwPrdX 0.024766,PwPrdY 0.024766 ||X:23.000000,Y:145.000000 ||fAppendix:0 | |EventID:0 || Time:15.000000 ||Hits:8 ||Etot:0.585572 ||LeftCx:28 TopCx:116 ||Width:4 Height:3 ||PwPrdX 1.273691,PwPrdY 1.512495 ||X:29.175123,Y:117.582939 ||fAppendix:0 | |EventID:0 || Time:14.000000 ||Hits:14 ||Etot:0.586113 ||LeftCx:40 TopCx:124 ||Width:6 Height:4 ||PwPrdX 1.857770,PwPrdY 1.386401 ||X:42.169643,Y:125.365417 ||fAppendix:0 | |EventID:0 || Time:11.750000 ||Hits:1 ||Etot:0.012057 ||LeftCx:46 TopCx:122 ||Width:1 Height:1 ||PwPrdX 0.012057,PwPrdY 0.012057 ||X:46.000000,Y:122.000000 ||fAppendix:0 | |EventID:0 || Time:20.000000 ||Hits:1 ||Etot:0.020091 ||LeftCx:46 TopCx:130 ||Width:1 Height:1 ||PwPrdX 0.020091,PwPrdY 0.020091 ||X:46.000000,Y:130.000000 ||fAppendix:0 |

K0L EventID:27

Event Size Caculation (TDC Info. +Crystal ID +Energy) * Multiplicity 20 bits 14 bits 14 bits 90 540Byte/Events

Simulation Events Data generated: K0L Event 0, Hits:32

Simulation Events Data generated: K0L Event 2, Hits:48

Gravity Position Calculation