LEPS Analysis Meeting

Kalman Filter of TPCana

Jia-Ye Chen2007.12.22

2007.12.22 LEPS Analysis Meeting

Outline

• Kalman Filter of TPCana• Criteria and cylindrical-coordinate framewo

rk1

• Monte Carlo Testing by single K+/K- in uniform B field.

• Real Data Study

1Extended Kalman Filter, K. Fujii, The ACFA-Sim-J Group.

2007.12.22 LEPS Analysis Meeting

Kalman Filter

• Equation of Motion is (quasi-) linear.• Many discrete points of measurements.• The distance between adjacent measurement

points is short.

2007.12.22 LEPS Analysis Meeting

Runge-Kutta vs Kalman Filter

2007.12.22 LEPS Analysis Meeting

Residual vs. Dip Angle

2007.12.22 LEPS Analysis Meeting

Residual vs. Momentum

2007.12.22 LEPS Analysis Meeting

Residual vs. Dip Angle & Mom.

2007.12.22 LEPS Analysis Meeting

Particle Identification

NEWEnergy Loss

(W/O saturated pulse reconstruction )

• Previous : hit’s central-pad peakADC

• Now : sum of (2 or 3) pads’ peakADC belong to one hit, to reduce the ambiguity from different avalanche ranges.

2007.12.22 LEPS Analysis Meeting

PID SliceMom. × Charge : 20 slices from -1.0 GeV/c to 1.0 GeV/c

2007.12.22 LEPS Analysis Meeting

Summary & Future Work

• Overall, 30% improvement in transverse residual, and 10% in longitudinal by utilizing Kalman Filter.

• To reduce the ambiguity between narrow and wider avalanche, sum of pads peakADC gives narrow PID band.

• Non-uniform B field of Kalman Filter• χ2 probability