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

结合KEK 12GeV质子同步加速器的实验，利用CERN的450GeV超级质子同步加速器和俄罗斯高能物理研究所的70GeV质子同步加速器进行了寻找非qq外来介子（胶球、混合体等）和新的手性对称粒子（sigma等）的实验，并在各研究所对所得数据进行了分析。探测器和前端电子器件的研发工作也在GAMS合作的框架下进行。在CERN，研究了中心产生反应pp→p_sX^0p_f（X^0=π^ π^-，π^0π^0，η η等），在IHEP和KEK，研究了电荷交换反应π^-p→X^0n X^-p（X^0= η π^0等X^-=η） π^- 等）主要被推崇。我们的 GAMS 小组于 1983 年首先发现的初级标量胶球候选 f_0（1500）/G1590），通过 CERN 和 IHEP 数据的新分析在相关通道（η η，η η' 等）中得到了证实。在 KEK 发现的 η π^- 通道中的非 qq 1^<- > 状态得到了其他两个小组的证实（MPS at IHEP 的 BNL 和 VES）。我们的 WA102 小组使用具有带电粒子和伽马检测能力以及粒子识别能力的 OMEGA 光谱仪研究了许多衰变通道中的许多共振。与日本大学理论小组合作研究了 Sigma 介子（作为戈德斯通玻色子的 π 的手性伴侣）。该介子在许多产生反应（pp 中心碰撞、J/φ 衰变、D 衰变等）的 π^0π^0 通道中的 500 MeV 质量区域附近可见。日本大学集团通过多个课题组的新思路和新方法，对散射过程中20年来未能解决的难题进行了研究和解决。利用新材料钨酸铅（PWO）制作了新型电磁热量计示波镜样机，并成功进行了测试。成功开发出一种具有世界最高水平的高速（小于1μ秒）和高线性分辨率（大于10位）的新型全定制ADC IC芯片。这些工作是在KEK与高能物理研究所合作协议的基础上进行的。该协议一直持续到2005年10月。更少

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