The sensitivity of the D^0-D^-0 mixing parameters x and y is estimated in the wrong-sign decay D^0→K^＋π^-π^0 by time-dependent amplitude analysis. The resolution of the D^0 lifetime is essential in time-dependent ...The sensitivity of the D^0-D^-0 mixing parameters x and y is estimated in the wrong-sign decay D^0→K^＋π^-π^0 by time-dependent amplitude analysis. The resolution of the D^0 lifetime is essential in time-dependent Dalitz analyses. The Belle II detector, which aims to collect a total integrated luminosity of 50 ab^-1 of data, has σ = 140 fs in Monte Carlo studies, a factor of two improvement over that of Belle and Ba Bar, so the produced Dalitz signal Monte Carlo samples are smeared with this resolution. Then a time-dependent Dalitz plot fitting is performed on these smeared samples, and the sensitivity of D^0-D^-0 mixing parameters are σx = 0.057% and σy = 0.049%. These are about an order of magnitude improvement on current experimental results, without considering background effects.展开更多
The doubly weak transition b-dd■ is highly suppressed in the Standard Model,which makes it a potential channel for exploring new physics signals.We present a study of the exclusive two-body wrong sign weak decay ■...The doubly weak transition b-dd■ is highly suppressed in the Standard Model,which makes it a potential channel for exploring new physics signals.We present a study of the exclusive two-body wrong sign weak decay ■→K+π-,which belongs to this class,in the perturbative QCD framework.We perform a model independent analysis for various effective dimension-6 operators for which large effects are possible.We further analyze the considered process in the Randall-Sundrum model,including the custodially protected and the bulk-Higgs Randall-Sundrum models.Exploring the experimentally favored parameter space of these models leads to a large and significant enhancement of the decay rate compared to the Standard Model,which might be accessible in future experiments.We propose to search for the wrong sign decay ■→K+π-via flavor-tagged time-dependent analyses,which can be performed at LHCb and Belle-Ⅱ.展开更多
Each year, hundreds of fatal wrong-way driving （WWD） crashes occur across the United States. Thousands of injuries are reported in crashes caused by wrong-way drivers. Traffic control devices （TCDs）, i.e., signs, ...Each year, hundreds of fatal wrong-way driving （WWD） crashes occur across the United States. Thousands of injuries are reported in crashes caused by wrong-way drivers. Traffic control devices （TCDs）, i.e., signs, pavement markings, and signals, have been introduced since 1935 to combat this problem. The aim of the paper is to provide a complete history of TCDs for deterring WWD on freeways and divided highways in previous versions of the Manual on Uniform Traffic Control Devices （MUTCD） （1935-2009）. A fully referenced overview of definitions, text passages, and figures of the TCDs, employed to deter WWD in all MUTCD versions, will be given to characterize the changes over time. In addition, the efforts that have been made by state department of transportation （DOT） especially over the past few years to aggressively attack WWD by deploying standard TCDs are reviewed. Finally, the paper makes conclusions and recommendations with regard to the necessity of a revision in the next edition of MUTCD for WWD TCDs. The investigation of changes and the current practice leave a trail to enable traffic engineers and policy makers to consider past decisions and their effectiveness in combating WWD, as well as providing a reference to determine whether or not their jurisdiction meets the MUTCD standards.展开更多
基金Supported by National Natural Science Foundation of China(11475164,11475169,11675166)
文摘The sensitivity of the D^0-D^-0 mixing parameters x and y is estimated in the wrong-sign decay D^0→K^＋π^-π^0 by time-dependent amplitude analysis. The resolution of the D^0 lifetime is essential in time-dependent Dalitz analyses. The Belle II detector, which aims to collect a total integrated luminosity of 50 ab^-1 of data, has σ = 140 fs in Monte Carlo studies, a factor of two improvement over that of Belle and Ba Bar, so the produced Dalitz signal Monte Carlo samples are smeared with this resolution. Then a time-dependent Dalitz plot fitting is performed on these smeared samples, and the sensitivity of D^0-D^-0 mixing parameters are σx = 0.057% and σy = 0.049%. These are about an order of magnitude improvement on current experimental results, without considering background effects.
基金Supported by National Science Foundation of China(11575151,11521505,11621131001)the Natural Science Foundation of Shandong Province(ZR2016JL001,ZR2019JQ04)+1 种基金the financial support from the Abdus Salam International Centre for Theoretical Physics during his visitfinancial support from CAS-TWAS president’s fellowship program 2014
文摘The doubly weak transition b-dd■ is highly suppressed in the Standard Model,which makes it a potential channel for exploring new physics signals.We present a study of the exclusive two-body wrong sign weak decay ■→K+π-,which belongs to this class,in the perturbative QCD framework.We perform a model independent analysis for various effective dimension-6 operators for which large effects are possible.We further analyze the considered process in the Randall-Sundrum model,including the custodially protected and the bulk-Higgs Randall-Sundrum models.Exploring the experimentally favored parameter space of these models leads to a large and significant enhancement of the decay rate compared to the Standard Model,which might be accessible in future experiments.We propose to search for the wrong sign decay ■→K+π-via flavor-tagged time-dependent analyses,which can be performed at LHCb and Belle-Ⅱ.
文摘Each year, hundreds of fatal wrong-way driving （WWD） crashes occur across the United States. Thousands of injuries are reported in crashes caused by wrong-way drivers. Traffic control devices （TCDs）, i.e., signs, pavement markings, and signals, have been introduced since 1935 to combat this problem. The aim of the paper is to provide a complete history of TCDs for deterring WWD on freeways and divided highways in previous versions of the Manual on Uniform Traffic Control Devices （MUTCD） （1935-2009）. A fully referenced overview of definitions, text passages, and figures of the TCDs, employed to deter WWD in all MUTCD versions, will be given to characterize the changes over time. In addition, the efforts that have been made by state department of transportation （DOT） especially over the past few years to aggressively attack WWD by deploying standard TCDs are reviewed. Finally, the paper makes conclusions and recommendations with regard to the necessity of a revision in the next edition of MUTCD for WWD TCDs. The investigation of changes and the current practice leave a trail to enable traffic engineers and policy makers to consider past decisions and their effectiveness in combating WWD, as well as providing a reference to determine whether or not their jurisdiction meets the MUTCD standards.
