We have developed an event mixing technique to observe Bose-Einstein correlations （BEC） between two identical neutral pions produced in photo-induced reactions in the non-perturbative QCD energy region. It is found ...We have developed an event mixing technique to observe Bose-Einstein correlations （BEC） between two identical neutral pions produced in photo-induced reactions in the non-perturbative QCD energy region. It is found that the missing-mass consistency cut and the pion-energy cut are essential for the event mixing method to effectively extract BEC observables. A Monte Carlo （MC） simulation is used to validate these constraints and confirms the efficiency of this method. Our work paves the way for similar BEC studies at lower energies where the multiplicity of emitted bosons is limited.展开更多
We present a new event mixing technique for measuring two-pion Bose-Einstein correlations （BEC） in reactions with only two identical bosons among three final state particles. This new mixing method contains a missin...We present a new event mixing technique for measuring two-pion Bose-Einstein correlations （BEC） in reactions with only two identical bosons among three final state particles. This new mixing method contains a missing mass consistency （MMC） cut and an energy sum order （ESO） cut. Unlike the previous proposed pion energy cut, which abandons nearly half the original events, the ESO cut does not eliminate any original events and hence improves the statistics of both original events and mixed events. Numerical tests using the γp→π0π0p events around 1 GeV are carried out to verify the validity of the ESO cut. This cut is able to reproduce the relative momentum distribution of the original events in the absence of BEC effects. In addition, its ability to observe BEC effects is tested by an event sample in the presence of BEC effects. Simulation results show the BEC effects can be observed clearly as an enhancement in the correlation function, and the BEC parameters extracted by this event mixing cut are consistent with the input BEC parameters.展开更多
基金Supported by Ministry of Education and Science of Japan(19002003)JSPS KAKENHI(24244022,26400287)
文摘We have developed an event mixing technique to observe Bose-Einstein correlations （BEC） between two identical neutral pions produced in photo-induced reactions in the non-perturbative QCD energy region. It is found that the missing-mass consistency cut and the pion-energy cut are essential for the event mixing method to effectively extract BEC observables. A Monte Carlo （MC） simulation is used to validate these constraints and confirms the efficiency of this method. Our work paves the way for similar BEC studies at lower energies where the multiplicity of emitted bosons is limited.
基金Supported by Fundamental Research Funds for the Central Universities(1006-YAH17063,1006-XAA18059)
文摘We present a new event mixing technique for measuring two-pion Bose-Einstein correlations （BEC） in reactions with only two identical bosons among three final state particles. This new mixing method contains a missing mass consistency （MMC） cut and an energy sum order （ESO） cut. Unlike the previous proposed pion energy cut, which abandons nearly half the original events, the ESO cut does not eliminate any original events and hence improves the statistics of both original events and mixed events. Numerical tests using the γp→π0π0p events around 1 GeV are carried out to verify the validity of the ESO cut. This cut is able to reproduce the relative momentum distribution of the original events in the absence of BEC effects. In addition, its ability to observe BEC effects is tested by an event sample in the presence of BEC effects. Simulation results show the BEC effects can be observed clearly as an enhancement in the correlation function, and the BEC parameters extracted by this event mixing cut are consistent with the input BEC parameters.
