FEE for TPC MPD__NICA JINR Yu.Zanevsky, A.Bazhazhin, S.Bazilev , S.Chernenko, G.Cheremukhina, V.Chepurnov, O.Fateev, S. Razin, V.Slepnev, A. Shutov, V. Vereschagin, V.Zryuev JINR, Dubna S. Chernenko, NECC2011, September 13, 2011 1

MPD NICA S. Chernenko, NECC2011, September 13, 2011 2

Time Projection Chamber (TPC) TPC parameters Size: 3.4 m (length) x 2.2 m (diameter) Drift Length: 150cm # of samples: 50 Electric field: 140V/cm Magnetic field: 0.5 T (max.) Gas: 90% Argon + 10% Methane (atm+2mbar) Readout: 2x12 sectors (MWPC+pads or GEM) Pad size – 4x10mm in inner sector area 6x12mm in outer sector area Total # of pads: ~80000 Performance Spatial resolution: srf~300 mm sz~ 2 mm Two track resolution < 1 cm Momentum resolution Dp/p < 3% (0.2<p<1 GeV/c) dE/dx resolution < 8% TPC prototyping has already started S. Chernenko, NECC2011, September 13, 2011 3

MPD TPC prototyping (2) MPD TPC read-out specification Field Cage Rods Diameter - 950 mm Length - 900 mm Wall thickness - 2 mm Material – Kevlar Readout – MWPC: 6x12 & 4x10 mm pads Gas – Ar/CH4 (80/20) MWPC readout MPD TPC read-out specification Readout: 2x12 sectors Pad size: 5x12,5mm Total # of pads: ~80.000 S. Chernenko, NECC2011, September 13, 2011 4 4 4

Front End Electronics Requirement Total number of channels............80.000 Smax/N………………………….…..30:1 @ MIP, noise < 1000e- Dynamic Range………………….. 1000 (10 bits) Shaping time …………………….. ~200ns (smooth shape, S/N) Sampling ……………................... 12.5 MHz Tail cancellation (after 1 s)…… < 1% Temperature……………………… ~ 0.10 C (stable drift velocit) Pcons …………………..……………..40mW/ch S. Chernenko, NECC2011, September 13, 2011

Front End Electronics Component Base FEE for TPC_MPD two ASICs from ALICE TPC : - PASA (analogue) - ALTRO (digital) REASONS - availability (total needed number of channels ) - reliability - good experience ● ALICE ~ 600.000 chs ● STAR ~ 140.000 chs (recent upgrade) - no long R&D S. Chernenko, NECC2011, September 13, 2011

STAR FEE Upgrade based on ALTRO+PASA (DAQ1000 ) > 10 times faster DAQ 1000 Old TPC features Zero suppression done at FEE in the Altro Event transfer 16-20 times smaller Combined with slightly faster link, will allow rates ~1000-5000 hz Event Buffering on FEE TPC stays alive as long as throughput is < max Deadtime only caused by TPC Drift.. 0.004% dead / hz readout Zero suppression done at RB in the DAQ room Full ~460,000 10 bit words transferred over each fiber. 10ms readout time every event. 100hz max rate. No event buffering on FEE TPC dead during digitization & readout time. 1% dead / hz readout. S. Chernenko, NECC2011, September 13, 2011

Data flow (rate) Track Signals readout Induced charge on pads Pad Plane Prototype ~ 3.000 chs Data flow (rate) - 1MB @ event (Z-suppresion  10% occupancy) - 6kHz trigger  5 GB @ TPC ~ 2 Gb per chamber - fast trtransmission + on-line data reduction (upgrade STAR, ~100times) to FEE S. Chernenko, NECC2011, September 13, 2011

64 chs FEE for TPC_MPD ALTRO ALTERA (control) TPC__MPD Readout L1: 6 kHz 4 CHIPS x 16 CH / CHIP 4CHIPS x 16 CH / CHIP drift region 40 ms Front-end Bus ALTRO Digital Circuit gating grid PASA Readout controller ADC RAM anode wire 80.000PADS pad plane CUSTOM IC (CMOS 0.35mm) CUSTOM IC (CMOS 0.25mm ) CSA SEMI-GAUSS. SHAPER 1 MIP = 4.8 fC S/N = 30 : 1 DYNAMIC = 30 MIP BASELINE CORR. TAIL CANCELL. ZERO SUPPR. 10 BIT < 10 MHz MULTI-EVENT MEMORY GAIN = 12 mV / fC FWHM = 190 ns S. Chernenko, NECC2011, September 13, 2011 9

Processing in PASA & ALTRO - FWHM – 190ns - Baseline restoration after 1ms: ~ 5 % in amplifier / shaper ~ 0.1% in dig. chip FWHM ~ 190ns PASA ALTRO - Baseline corrections - Tail cancellation S. Chernenko, NECC2011, September 13, 2011 10

Conclusion - TPC is optimal tracking Detector for MPD ( high multiplicity environment, possibility for dE/dx measurement ) - TPC prototyping is in a good progress now ( development of field cage, pad plane, FEE and so on; test with the laser ) - FEE is based on ALTRO and PASA chips (ALICE TPC) ALTRO and PASA are available and can provide all required parameters - FEE prototyping is being planned to be completed in 2012 - TPC installation into MPD is being planned to be completed in 2016 S. Chernenko, NECC2011, September 13, 2011 11

Thank you for attention S. Chernenko, NECC2011, September 13, 2011 12