Study on Meson Spectroscopy-Search for Exotic States

介子能谱研究——寻找奇异态

• 批准号: 63044143
• 负责人: TAKAMATSU Kunio
• 金额: $ 7.68万
• 依托单位: National Laboratory for High Energy Physics
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63044143/
• 关键词: Hadron Spectroscopy; GAMS; electromagnetic calorimeter; CERN IHEP (Protuino) KEK; meson resonances; exotic states; Analyses; machine time runs

The collaboration project of the GAMS experiment among CERN, IHEP (Protuino) and KEK took shape promoting the occasion of the 2nd International Conference on Hadron Spectroscopy held at KEK in 1987. GAMS is a nickname of the electromagnetic calorimeter hodoscope of a total absorption type which detects gamma rays decaying from a neutral meson state. The GAMS experiment started as an international collaboration between CERN and IHEP in 1978 in the framework of the 6th joint CERN-IHEP experiment. The GAMS program covers the research activity that is taking place around two Electromagnetic Spectrometers which are GAMS-2000/4pi at IHEP and GAMS-4000 (NA12/2) at CERN. The collaboration activities are supported by the following institutions ; LAPP of France, IISN of Belgium, Pisa Univ. of Italy, LANL of USA, IHEP of USSR and KEK of Japan.The main line of the GAMS project is a systematic search for new neutral light meson resonances including exotic states (glueballs, hybrids and others) and … More for new rare neutral decay modes of known meson resonances. These neutral mesons which decay into multiーgamma rays are produced in two exclusive processes ; pi^-p charge exchange reactions and central collisions of hadrons. Pions and protons ranging between 100 and 400 GeV/c produced by the 450 GeV SPS at CERN and pions between 30 and 40 GeV/c produced by the 70 GeV PS at IHEP have been used in the reactions. GAMS has already observed several new states, among which G(1590)/f_0(1590) is prominent. It is a scalar state which decays into etaeta, etaeta' and 4pi and is considered as a candidate of a glueball. M (1405) is an important object which has been found in etapi^0 decay mode. Its quantum numbers are J^<PC>=1^<-+> which are qq exotic. Activities in the same direction have been also pursued at KEK. Meson states including exotics are searched for by using the charge and gamma spectrometer, Benkei at the 12 GeV Proton Synchrotron at KEK. The GAMS collaboration forms, now, a combined experimental program performed by the three institutions.During 1988-1990, the GAMS collaboration executed machine time runs in June-August at CERN and in NovemberーDecember at IHEP in each year. The data summary tapes have been delivered to each institutions. Analyse are under way. Meanwhile, the data acquisition system has been improved by using a VME system in order to filter events and to maximize acquisition time in both GAMS-4000 and GAMS-4pi. GAMS-2000 is upgraded to GAMS-4pi augmenting the solid angle coverage by adding the guard system around the hydrogen target and the wide angle calorimeter system. Large drift chambers have been installed for detecting charged particles.The GAMS project is scheduled to continue to accumulate data till 1993. Less

欧洲核子研究中心、IHEP（Protuino）和科索沃能源公司之间的GAMS实验合作项目的形成，促进了1987年在科索沃能源公司举行的第二届国际强子光谱学会议。GAMS是全吸收型电磁量热计的昵称，它检测从中性介子状态衰减的伽马射线。GAMS实验始于1978年CERN和IHEP在第六次CERN-IHEP联合实验框架内的国际合作。GAMS计划涵盖了围绕IHEP的GAMS-2000/4pi和CERN的GAMS-4000（NA 12/2）两台电磁光谱仪进行的研究活动。合作活动得到了下列机构的支持：法国LAPP、比利时IISN、意大利比萨大学、美国LANL、苏联IHEP和日本KEK。GAMS项目的主线是系统地寻找新的中性轻介子共振，包括奇异态（胶球、混合态等）， ...更多信息 已知介子共振的新的稀有中性衰变模式。这些衰变为多重γ射线的中性介子是在两个独特的过程中产生的：π ^-p电荷交换反应和强子的中心碰撞。在反应中使用了由CERN的450 GeV SPS产生的100和400 GeV/c之间的π子和质子，以及由IHEP的70 GeV PS产生的30和40 GeV/c之间的π子。GAMS已经观测到了几个新的态，其中G（1590）/f_0（1590）是最突出的。它是一个标量态，衰变为η eta，η eta '和4 π，被认为是胶球的候选者。M（1405）是在Etapi^0衰变模式下发现的一个重要天体。它的量子数是J^<PC>=1^&lt;-+&gt;，这是qq奇异的。科索沃能源公司也在同一方向开展活动。使用KEK 12 GeV质子同步加速器上的电荷和伽马光谱仪Benkei来搜索包括稀有元素在内的介子态。1988-1990年期间，GAMS合作组每年在CERN和IHEP分别于6 - 8月和11 - 12月进行机器时间运行。数据摘要磁带已送交各机构。分析正在进行中。同时，在GAMS-4000和GAMS-4pi中，通过使用VME系统对数据采集系统进行了改进，以过滤事件并最大化采集时间。GAMS-2000升级为GAMS-4pi，通过增加氢靶周围的防护系统和广角量热计系统来扩大立体角覆盖范围。已经安装了大型漂移室来探测带电粒子，GAMS项目计划继续积累数据，直到1993年。少

项目成果

K.TAKAMATSU: "EXPERIMENTAL STUDIES ON MESON SPECTROSCOPY AT KEK" PROCEEDINGS OF THE III^<RD>INTERNATIONAL CONFERENCE ON HADRON SPECTROSCOPY,AJACCIO,CORSILA,1989 ED.F・BINON ET AL.EDITION FRONTIERES. 72-81 (1989)

K.TAKAMATSU：“KEK 介子光谱实验研究”第三届强子光谱国际会议论文集，AJACCIO，CORSILA，1989 ED.F·BINON 等版 FRONTIERES 72-81 (1989)。

S.INABA ET AL.: "LOW POWER TDC AND QUC CIRCUITS FOR BALLOON BORNE EXPERIMENTS" IEEE TRANSACTIONS ON NUCLEAR SCIENCE. 37. 412-416 (1990)

S.Inaba 等人：“气球载实验的低功耗 TDC 和 QUC 电路”IEEE 核科学交易。

S. INABA Et Al.: "Low Power Tdc and Ovc Circuits for Balloon Borne Experiments" Ieee Transaction on Nuclear Science. 37. 412-416 (1990)

S. INABA 等人：“用于气球载实验的低功率 Tdc 和 Ovc 电路”，IEEE Transaction on Nuclear Science。

S. FUKUI Et Al.: "Study of omegaPI^ﾟ System in the PI^-P Change Exchange Reaction at 8.95GeV/c" KEK-Preprint. 90-167. (1990)

S. FUKUI 等人：“8.95GeV/c PI^-P 变化交换反应中 omegaPI^ﾟ 系统的研究”KEK-预印本 (1990)。

K. TAKAMATSU: "Experimental Studies on Meson Spectroscopy at KEK" Proceedings of the III^<RD> International Conference on Hadron Spectroscopy, Ajaccio, Corsica, 1989, Ed. By F. Binon Et Al. , Edition Frontieres. 72-81 (1989)

K. TAKAMATSU：“KEK 介子光谱实验研究”第三届强子光谱国际会议论文集，阿雅克肖，科西嘉岛，1989 年，编辑。