检索结果-南通市图书馆

New g-2 experiment at J-PARC

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2010年第6期34卷 745-748页

作者： Tsutomu Mibe kek High Energy Accelerator Research Organization

A new measurement of the anomalous magnetic moment of the positive muon αμ is proposed with a novel technique utilizing an ultra-cold muon beam accelerated to 300 MeV/c and a 66 cm-diameter muon storage ring without focusing-electric field. This measurement will be complimentary to the previous measurement that achieved 0.54 ppm accuracy with the magic energy of 3.1 GeV in a 14 m diameter storage ring. The proposed experiment aims to achieve the sensitivity down to 0.1 ppm.

关键词： muon anomarous magnetic moment J-PARC

Calculation of the external quality factor of the high power input coupler for the BEPCⅡ superconducting cavity

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2008年第1期32卷 72-74页

作者：黄彤明潘卫民王光伟 T.Furuya S.Mitsunobu Institute of High Energy Physics CAS kek Tsukuba-shi 305-0801 Japan

It is very important to predict the coupling between the cavity and the high power input source in the coupler design. In this paper, a time domain method is used to calculate the external quality factor Qext for the BEPC Ⅱ superconducting cavity. A comparison between simulation results and experimental results is presented. The results of simulation and measurement of Qext have a good agreement within an error of 10%. The geometry parameters related with Qext are also studied.

关键词： high power input coupler external quality factor superconducting cavity

THE CKM QUARK-MIXING MATRIX

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2016年第10期40卷 224-232页

作者： A. Ceccucci Z. Ligeti Y. Sakai CERN LBNL kek

12.1. Introduction The masses and mixings of quarks have a common origin in the Standard Model （SM）. They arise from the Yukawa interactions with the Higgs condensate,

关键词：

Mitigating the effects of higher order multipole fields in the magnets of the Accelerator Test Facility 2 at kek

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2012年第8期36卷 756-760页

作者：白莎 P. Bambade 王逗高杰 M. Woodley M. Masuzawa Institute of High Energy Physics (IHEP) LAL Univ Paris-Sud CNRS/IN2P3 Orsay France SLAC Menlo Park California USA kek Tsukuba Ibaraki Japan

The ATF2 project is the final focus system prototype for the ILC and CLIC linear collider projects, with the purpose of reaching a 37nm vertical beam size at the interaction point. In the nanometer beam size regime, higher order multipoles in magnets become a crucial point for consideration. The strength and rotation angle of the ATF2 QEA magnets were reconstructed from the IHEP measurements and compared with the kek ones to be identical. Based on the study of the skew multipoles sensitivity, we report on the analysis of the possible mitigation of the measured multipoles. A suggestion is given which will benefit the ATF2 present commissioning to reach the goal beam size, and also the reduced β optics in future.

关键词： ATF2 beam size higher order multipoles QEA magnets

Study of ππ production in two-photon collisions at Belle

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2008年第6期32卷 499-503页

作者： S.Uehara IPNS-kek Institute of Particle and Nuclear StudiesHigh Energy Accelerator Research OrganizationTsukubaJapan

We have measured the cross section for π^＋π^- production in two-photon collisions using a data sample with an integrated luminosity of 85.9 fb^-1 collected with the Belle detector. The f0（980） resonance is observed as a peak in the energy spectrum of the cross section. We also report preliminary results for γγ→ π^0π^0 with two-photon center-of-mass energies ranging from 0.6 to 4.0 GeV, based on a 95 fb-1 data sample. We find at least four resonant structures including a peak from f0（980）. In addition, there is evidence for Xc0 production. We also make a preliminary discussion of the angular dependence and cross section ratio of γγ →π^＋π^- and γγ→π^oπ^o.

关键词： two-photon collisions pion cross section resonances charmonia

Stop band characteristics of a TESLA cavity coaxial-type HOM coupler

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2009年第5期33卷 401-405页

作者：王尔东王芳张保澄野口修一渡边谦赵夔 Institute of Heavy Ion Physics Peking University kek: High Energy Accelerator Research Organization

A TTF-type coaxial higher order modes （HOM） coupler has been used in a TESLA 9 cell cavity. It is impossible to measure the stop band characteristics of the HOM coupler with the cavity. A measurement device for the coaxial transmission line type for the HOM coupler has been designed at Peking University. Experimentally it was shown that the average voltage standing wave ratio of the coaxial transmission line is smaller than 1.08. The experimental results of the stop band characteristics of the TTF-type HOM coupler have been fitted for the simulation. This paper describes the design of the measurement device and discusses the experimental and simulation results of stop band characteristics of the HOM coupler.

关键词： HOM coupler notch filter stepped coaxial transmission line stop band characteristics

LATTICE QUANTUM CHROMODYNAMICS

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2016年第10期40卷 310-320页

作者： S. Hashimoto J. Laiho S.R. Sharpe kek Syracuse University University of Washington

Many physical processes considered in the Review of Particle Properties （RPP） involve hadrons. The properties of hadrons--which are composed of quarks and gluons--are governed primarily by Quantum Chromodynamics （QCD）（with small corrections from Quantum Electrodynamics [QED]）. Theoretical calculations of these properties require non-perturbative methods, and Lattice Quantum Chromodynamics （LQCD） is a tool to carry out such calculations. It has been successfully applied to many properties of hadrons. Most important for the RPP are the calculation of electroweak form factors, which are needed to extract Cabbibo-Kobayashi-Maskawa （CKM） matrix elements when combined with the corresponding experimental measurements. LQCD has also been used to determine other fundamental parameters of the standard model, in particular the strong coupling constant and quark masses. This review describes the theoretical foundations of LQCD and sketches the methods used to calculate the quantities relevant for the RPP. It also describes the various sources of error that must be controlled in a LQCD calculation. Results for hadronic quantities are given in the corresponding dedicated reviews.

关键词：

A Multi-MW Proton/Electron Facility at kek

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Applied Mathematics and Physics 2017年第6期5卷 1222-1242页

作者： R. Belusevic IPNS High Energy Accelerator Research Organization (KEK) Ibaraki Japan

The main “bottleneck” limiting the beam power in circular machines is caused by space charge effects that produce beam instabilities. To increase maximally the beam power of a “proton driver”, it is proposed to build a facility consisting solely of a 2.5 GeV injector linac (PI) and a 20 GeV pulsed superconducting linac (SCL). Such a facility could be constructed using the existing kek accelerator infrastructure. The PI, based on the European Spallation Source (ESS) linac, would serve both as an injector to the SCL and a source of proton beams that could be used to copiously produce, e.g., muons and “cold” neutrons. Protons accelerated by the SCL would be transferred through the kek Tristan ring in order to create neutrino, kaon and muon beams for fixed-target experiments. At a later stage, a 70 GeV proton synchrotron could be installed inside the Tristan ring. The SCL, comprising 1.3 GHz ILC-type rf cavities, could also accelerate polarized or unpolarized electron beams. After acceleration, electrons could be used to produce polarized positrons, or may traverse an XFEL undulator.

关键词： Proton Driver Superconducting Linac Neutrino Oscillations Rare Kaon Decays XFEL

Tuning of RF amplitude and phase for the drift tube linac in J-PARC

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2009年第7期33卷 577-582页

作者：沈国保 Masanori Ikegami Japan Atomic Energy Agency(JAEA) 2-4 Shirakata-Shirane High Energy Accelerator Research Organization(kek)

The J-PARC linac has three DTL tanks to accelerate the negative hydrogen ions from 3 MeV to 50 MeV. The RF phase and amplitude are adjusted for each cavity with a phase scan method within the accuracy of 1° in phase and 1% in amplitude. The experimental results show a remarkable agreement with the numerical model within a suffcient margin in the tuning of the last two DTL tanks. However,a notable discrepancy between the experiment and the numerical model is seen in the tuning of the first DTL tank. After studying with a three-dimensional multi-particle simulation,the generation of the low energy component and the pronounced filamentation are identified as the main causes of the discrepancy. The optimization of the tuning scheme is also discussed to attain the tuning goal accuracy for the first DTL tank.

关键词： high-intensity beam drift tube linac signature matching J-PARC