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Analysis of Tagger high resolution TDC for separating RF. 2004. 7. 14 Hideki Kohri. Mass spectrum. r29511 - 29514. Momentum (GeV/c). Although we started taking high resolution TDC data of tagger PL for improving mass spectrum, the mass spectrum was improved
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Analysis of Tagger high resolution TDC for separating RF 2004. 7. 14 Hideki Kohri
Mass spectrum r29511 - 29514 Momentum (GeV/c) Although we started taking high resolution TDC data of tagger PL for improving mass spectrum, the mass spectrum was improved by considering the flight time between target and start counter. But the TDC data of tagger PL can be also used for TPC trigger counter. Mass / charge GeV/c2
Tagger high resolution TDC analysis Tagger PL#3 ADC ADC rfrawTDC-TagTDC After slewing correction TDC channel TDC channel RMS 330ps What makes tail? TDC channel SUM
Correlation between two PL’s Tagger multiplicity 2 events RF bunch number PL#3 RF bunch number PL#2 RF bunch PL#3 - PL#2 # of +1 / # of 0 = 3.3 % # of -1 / # 0f 0 = 4.5 %
Pion events Good pions: Pions whose RF is correctly identified by LEPS spectrometer Solid : good pions Dashed: bad pions RF number LEPS - TaggerPL RF number LEPS - TaggerPL Momentum (GeV/c) Abilities of start counter and tagger PL for separating RF are not so different. Advantage of using tagger PL TDC for forward spectrometer analysis seems to be small. But it would be a help for TPC analysis. Mass/charge GeV/c2
Particle ID by new start counter r29552 - 29556 Sigma = 28 MeV/c2 Momentum (GeV/c) Mass / charge (GeV/c2) There are some events whose RF is not correctly identified. Currently, it is difficult to say that new start counter is better than old one. Mass / charge GeV/c2