流水线时钟24ns4165L162μs02REF4998M2nsTOF.PPT

Event Start Time Determination Ma Xiang 2005.9.21 Contents The Inf. from MDC, TOF Trigger system Why need to Cal. Event Start Time? Principle of ESTime Calculation. ESTime Cal. by TOF ESTime Cal. by MDC Status of ESTime some results Next to do TDC measured by TOF Why need to Cal. Event Start Time(1)?不同粒子种类、不同能量引起的事例起点的不确定性 Why need to Cal. Event Start Time(2)?触发周期引起的事例起点的不确定性:? 50 ns Principle of the ESTime Calculation(1) 1. Event type: Beam collision Cosmic 2. Fast Tracking Particle ID 1) MDC Fast Tracking 2) EMC tracking 3) dE/dx 4) Particle ID 3. ESTime Calculation method * by TOF Information ( barrel endcap) * by MDC fast tracking Information * by MDC Information itself Principle of the ESTime Calculation(2) UML Class Diagram(ESTime part) UML Class Diagram ESTime Calculation by TOF ESTime Calculation Flow 现状 result e-,1GeV,10000 MC Testset to”0” Test Measured : 1.Forward : Mean time: 0.09ns σ: 0.50ns 2.Backward : Mean time: 0.042ns σ: 0.47ns result p ,1.5GeV,1000 MC data Testset to”0” Test measured: 1.Forward : Mean time: 0.42ns σ: 0.52ns 2.Backward : Mean time: 0.42ns σ: 0.52ns “Lund” 6000 MC data, Test set to”0” Test Measured 1.Forward : Mean time: 0.12ns σ: 0.77ns 2.Backward : Mean time: 0.084ns σ: 0.75ns “Lund” 6000 MC data, Test set to “2”, “10”, “18” Next to do Endcap TOF need to consider dE/dx EMC tracking have not included Calculating event start time by MDC fast track (No TOF information) result need to check MDC tracking (without MDC fast tracking) calculate event start time (by Zhangling) Cosmic Belle 时间分辨 Bhabha: TOF：0.4ns MDC：1.3ns 事例起始时间图 * * * * * TOF1 TOF2 流水线时钟 L1 24ns REF 500MHZ 2ns TOF mean MDC-TRK ＊ The Inf. from MDC, TOF Trigger system 6.2μs?0.2 TOF1(hit) TOF2(hit) 流水线时钟 (24ns 41.65) L1 6.2μs?0.2 REF (499.8M 2ns) TOF-Tmean MDC-TRK ＊ TOF1-TDC MDC-TDC TOF2-TDC The Inf. from MDC, TOF