1. Pile-Up Pulse Decomposition Jia-Ye Chen 2007.08.06

2. Outline Why to study Pile-up Pulse? Pile-up Pulse Decomposition Study Pulse Identification Algorithm : Original vs New Fitting (Normal, Pileup, Shoulder and Saturated) : Well Efficiency : Same as original one Residual : 1 % improvement Event Display of Trouble What I ever tried …

3. Time Projection Chamber

4. Get Pulse Form Cluster Get Pulses & Form Clusters

5. Set Hits & Find Track Candidates Set Hits (0.46) Find Track Candidates 2D 3D Hit Position

6. Particle Identification Algorithm

7. Pulse Identification Algorithm Original : nextPeakAdc – prevMinAdc > 15 Pile-up Pulse peakAdc > threshold (dynamic threshold) Separation of peakTdc > 2 clocks Pulse valley away from prevPeakTdc > 2 clocks Shoulder Pulse ( By Su-Yin Wang ) Δ(ΔADC ) < -8. Separation to neighboring peakTdc > 3.

8. Single Pulse

10. Pile-up Pulse

12. Shoulder Pulse

15. Pile-up & Shoulder Pulse

16. Saturated Pulse

19. Current Algorithm Deal with 2-pulse segment ONLY. Pulse width is the same as previous one Use TDC of 1/5 peakADC ” in the raising edge. Rebuild new pulses within the ranges o f old pulse widths. 3 segments within 3 individual pads have the same number of pulses.

20. Parameter for Pile-up adcForPileup = nextPeakAdc – prevMinAdc > 15

21. adcForPileup = 12.adcForPileup = 10.

22. adcForPileup = 8.adcForPileup = 5.

24. Event Display

40. What I ever tried New Pulse Identification Algorithm Pile-up, Shoulder, Saturated, and coupled. Number of pulses per segment <= 5 ADC sorting -> TDC sorting Rebuild new Pulse with new pulse width Use “ TDC of peakAdc ” instead of “ TDC of 1/5 peakADC ” in the raising edge.