Search for Exotic Mesons with High Precision Gamma-ray Detector (GAMS)

寻找非QQ奇异介子(胶球、杂化粒子等)的实验和新的手性对称粒子(Sigma等)欧洲核子研究中心的450GeV超级质子同步加速器和俄罗斯IHEP的70GeV质子同步加速器与KEK的12GeV质子同步加速器的实验相关联，并对所获得的数据进行了分析。在欧洲核子研究中心，中心产物反应pp→p_sx^0p_f(X^0=π^+π^-，π^0π^0，ηη等)主要研究了电荷交换反应π^-p→X^0n X^-p(X^0=ηπ^0等)，并在有关通道(ηπ‘等)中证实了1983年本课题组首次发现的主要标量胶球候选者f_0(1500)/G1590。通过对CERN和IHEP数据的最新分析，证实了在KEK发现的ηπ^-通道中的非QQ1^-+态被另外两个组(BNL的MPS和IHEP的VES)所证实。许多…中存在许多共振我们的WA102小组使用具有带电粒子和伽马探测能力和粒子识别能力的欧米伽谱仪研究了更多的衰变通道，并与日本大学理论小组合作研究了π的手性伙伴--Goldstone玻色子--Sigma介子。这个介子在π^0π^0通道的500 MeV质量区附近可以看到，它是许多产生反应(PP中心碰撞、J/φ衰变、D衰变等)的产物。利用几个小组的新思想和日本大学小组的新方法，研究并解决了20年来一直没有解决的散射过程中的难题。利用新材料钨酸铅(PWO)建立了一种新型电磁量热计示波器的原型，并成功地进行了测试。一种新的全定制高速(小于1μ秒)模数转换器芯片这些工作是在KEK和IHEP合作协议的基础上进行的，该协议一直持续到2005年10月。较少

Experiments of search for non-qq exotic mesons (glueballs, hybrids etc.) and new chiral symmetry particles (sigma etc.) were performed using 450GeV Super Proton Synchrotron at CERN and 70GeV Proton Synchrotron at IHEP (Russia) in relation with experiments at 12GeV Proton Synchrotron at KEK, and the obtained data were analyzed at each institute. R＆D works of detectors and front end electronics were also done in the framework of the GAMS collaboration.At CERN, central production reactions pp→p_sX^0p_f (X^0=π^+ π^-, π^0π^0, η η etc.) were studied and at IHEP and KEK, charge exchange reactions π^-p→X^0n X^-p (X^0= η π^0 etc.X^-=η π^- etc) are mainly persued.A primary scalar glueball candidate f_0(1500)/G1590) which was found firstly by our GAMS group in 1983, was confirmed in relevant channels (η η, η η' etc.) by the new analyses of CERN and IHEP dataA non-qq 1^<-+> state in the η π^- channel found at KEK was confirmed by other two group (MPS at BNL and VES at IHEP).Many resonances in many … More decay channels were studied by our WA102 group using the OMEGA spectrometer with detection capability of charged particles and gammas and particle identification.The sigma meson, a chiral partner of π as a Goldstone boson, was studied with collaboration with the theoretical group of Nihon University. This meson was seen around the 500 MeV mass region in π^0π^0 channel of many production reactions (pp central collision, J/φ decay, D decay etc.). The difficult problems in the scattering process, which had not been solved for 20 years, was studied and solved on new ideas of several groups and the new method of Nihon-Univ.group.A prototype of a new electromagnetic calorimeter hodoscope using new material, lead tungstate (PWO) was built and successfully tested. A new full-custom IC chips for ADC with high speed (less than 1 μ sec.) and high linearity resolution (more than 10bits) was developed successfully with the best level in the world.These works were performed on the basis on agreement on collaboration between KEK and IHEP.The agreement is continued till October of 2005. Less