Measurements Of E⁺e^-→K_S⁰K^±π^?π⁰（η） At BESⅢ And Preliminary Study Of CEPC Luminometer

The Standard Model of particle physics has made a big achievement in description of three fundamental interaction(strong,weak,and electromagnetic interaction)of matter.The quantum chromodynamics(QCD),which is used to describe the strong interaction,has been well validated by experiment in the high energy region.In the low energy region QCD has the asymptotic freedom property.However,the behaviour of QCD in the low energy region is non-perturbative,the calculation of strong interaction is still model dependent.At present,all hadrons observed by experiments are mesons(qq containing a quark and a anti-quark),or baryons(qqq containing three quarks).The QCD predicted exotic hadron structure,such as multi-quark stats,hybrid states,and glue-balls have not been surely confirmed by experiments.Recent years,some exotic states,called XYZ states,were discovered by experiments and may be the candidates of the exotic hadron states.BESIII is a ideal platform to study these XYZ states.Using 5.2 fb-1 e+e-annihilation data samples collected with the BESIII detector,we measure the cross sections of e+e-→KS0K±π(?)π0 and KS0K=π=η at 17 center-of-mass energies from 3.90 to 4.60 GeV.In addition,we search for the charmoniumlike resonance Y(4260)decays into KS0K±π(?)π0 and KS0K±π(?)η and Zc0,±(3900)decays into KS0K±π(?),0and KS0K±η.Corresponding upper limits at 90%C.L.are provided since no clear signal is observed.The discovery of higgs boson,which was predicted by Standard Model,is a strong support of the Standard Model.After that,it’s important to precisely measure the prop-erties of the Higgs boson and the dynamics of interactions between Higgs boson and the other element particles.The Chinese physicists initialled a large scientific project named CEPC,which is shorten for the Circular Electron-Positron Collider.The CEPC is aiming at the precise measurements of Higgs and Z/W bosons.Therefore,the pre-cision of luminosity measurement is very important to the CEPC physical targets.To reach a very precise luminosity,there is a luminosity calorimeter(LumiCal)in CEPC detector design.Depend on the current geometry design,the conventional track recon-struction method solve suffers the energy leakage problem when tracks falling into the tile gap regions.To solve this shortcoming,a novel reconstruction method based on deep neural networks has been investigated.Four deep neural network models in two shapes are obtained.Compared to the conventional method,the reconstruction effi-ciency has been improved significantly,as well as the energy and direction resolutions Besides,the shower leakage problem and the upstream material budgets are discussed The former is about the secondary particles generated in LumiCal and fly into the time projection chamber of CEPC.The latter is related to the energy loss of incident particle before entering LumiCal.