Project of a Super Charm-Tau factory at the Budker Institute of Nuclear Physics in Novosibirsk

A project of a Super Charm-Tau factory is being developed at the Budker Institute of Nuclear Physics (Siberian Branch, Russian Academy of Sciences) in Novosibirsk. The electron-positron collider to be employed will operate at c.m. energies in the range between 2 and 5 GeV at an unprecedentedly high luminosity of 10³⁵ cm^?2 s^?1 with a longitudinal electron polarization at the beam-interaction point. The main objective of experiments at the Super Charm-Tau factory is to study processes involving the production and properties of charmed quarks and tau leptons. A high luminosity of this setup will make it possible to obtain a statistical data sample that will be three to four orders of magnitude vaster than that from any other experiment performed thus far. Experiments at this setup are assumed to be sensitive to effects of new physics beyond the Standard Model. Investigations to be carried out at the Super-Charm-Tau factory will supplement future experiments at Super-B factories under construction in Italy and in Japan.     

Physics possibilities at a linear collider

We review some recent studies about the parameter determination of top quarks,W bosons, Higgs bosons, supersymmetric particles and in the ADD model of extra dimensions at a linear collider.     

Dark matter constraints on gaugino/Higgsino masses in split supersymmetry and their implications at colliders

In split supersymmetry, gauginos and Higgsinos are the only supersymmetric particles that are potentially accessible at soon-to-be-completed colliders. While direct experimental research, such as the LEP and Tevatron experiments, have given robust lower bounds on the masses of these particles, cosmic dark matter can give some upper bounds and thus have important implications for research at future colliders. In this work we scrutinize such dark matter constraints and show the allowed mass range for charginos and neutralinos (the mass eigenstates of gauginos and Higgsinos). We find that the lightest chargino must be lighter than about 1 TeV under the popular assumption M₁=M₂/2 and about 2 or 3 TeV in other cases. The corresponding production rates of the lightest chargino at the CERN large hadron collider (LHC) and the International Linear Collider (ILC) are also given. While in some parts of the allowed region the chargino pair production rate can be larger than 1 pb at the LHC and 100 fb at the ILC, other parts of the region correspond to very small production rates, and thus there is no guarantee of finding the charginos of split supersymmetry at future colliders. PACS 14.80.Ly, 95.35.+d     

Muon Physics Possibilities at a Muon-Neutrino Factory

New intense proton accelerators with above GeV energies and MW beam power, such as they are discussed in connection with neutrino factories, appear to be excellently suited for feeding bright muon sources for low-energy muon science. Muon rates with several orders of magnitude increased flux compared to present facilities will become available. This will allow higher precision in experiments which were statistics limited so far such as searches for rare decays, muonium spectroscopy, muon capture, muon catalyzed fusion, muon decay studies and measurements muon moments and parameters. Novel and most important experiments will become possible. For example a permanent electric dipole moment (edm_μ) of a muon could be searched with by far unprecedented accuracy and with a physics potential well beyond the possibilities of present electron, neutron and nuclear edm searches. Investigations of short lived radioactive nuclei using muonic atom spectroscopy would become feasible. This revised version was published online in August 2006 with corrections to the Cover Date.     

An investigation of hadronization mechanism at a Z~0 factory

We briefly review the hadronization pictures adopted in the LUND String Fragmentation Model (LSFM),Webber Cluster Fragmentation Model (WCFM) and Quark Combination Model (QCM),respectively.Predictions of hadron multiplicity,baryon to meson ratios and baryon-antibaryon flavor correlations,especially those related to heavy hadrons at a Z 0 factory obtained by LSFM and QCM,are reported.     

Testing discrete symmetries at a super τ -charm factory

Tests of discrete symmetry violation have played an important role in understanding the structure of weak interactions in the Standard Model of particle physics. Historically, these measurements have been extensively performed in experiments with large samples of K and B mesons. A high luminosity τ-charm facility presents physicists with the opportunity to comprehensively explore discrete symmetry violation and test the Standard Model using τ leptons, charm mesons, and charmed baryons. This paper discusses several possible measurements for a future τ-charm factory.     

关于在HIAF-BRing上开展自旋物理研究的提议(英文)

国家重大科技基础设施"强流重离子加速器装置"（High Intensity heavy-ion Accelerator Facility,HIAF）已由国家发改委批准立项并开始建设。建成之后,HIAF将为微观物质结构和重离子应用等研究提供很好的实验平台。HIAF的加速储存环（Booster Ring,BRing）设计可以加速最高动量为11.9 GeV/c的高流强质子束流。因此,HIAF-BRing将为GeV能区的核物理和强子物理研究带来新的机遇。另一方面,极化实验是研究微观物质及其相互作用的有力工具。我们提议启动相关物理和极化技术的预研工作,为在HIAF-BRing上开展自旋物理研究打下基础。The construction of the future scientific facility High Intensity heavy-ion Accelerator Facility (HIAF) in China has started. Once established, HIAF will provide excellent conditions for fundamental investigations on both matter structure and heavy-ion applications. The booster ring (BRing) of HIAF is designed to accelerate high-intensity protons with the maximum momentum of 11.9 GeV/c. Therefore it will bring new opportunities for the nuclear and hadron physics in the GeV region. Polarized experiments have been proved as a powerful tool in the explorations of the building blocks of matter. We propose to initiate a pre-investigation for the related physics and polarization techniques, which will lay the foundation of the spin physics at the HIAF-BRing.     

Sensitivity study of anomalous HZZ couplings at a future Higgs factory

We study the sensitivity of constraining the model independent HZZ coupling based on the effective theory up to dimension-6 operators at a future Higgs factory. Using the current conceptual design parameters of the Circular Electron Positron Collider, we give the experimental limits for the model independent operators given by the total Higgsstrahlung cross-section and the angular distribution of Z boson decays. In particular, we give the very small sensitivity limit for the CP violation parameter g, which will be a clear window to test the Standard Model and look for new physics signals     

Physics prospects at J-PARC

We have held an inauguration ceremony of the Japan Proton Accelerator Research Complex (J-PARC) on July 6, 2009, celebrating the completion of its construction. Now, the beam commissioning of the 50 GeV main proton synchrotron is in progress to improve the beam intensity and quality. A lot of important experimental programs in Nuclear Physics are waiting for the beam. In this report, I introduce some examples.     

Spin Physics at ANKE-COSY

The COSY accelerator (Jülich, Germany) provides beams of polarised protons and deuterons. The ANKE facility at COSY is equipped with polarised hydrogen and deuterium atomic gas targets. The reactions investigated with polarised probes at ANKE include the deuteron break-up at small and large momentum transfer, the pion production processes in pp and pn collisions and the near-threshold η meson production in dip $\vec dp \to ^3 He\eta$ process. Use of the polarised deuteron beam properties allowed a precision measurement of the η meson mass. The future experimental program covers the study of the elementary pp and pn-interaction with polarised beams up to the maximal COSY energy, and a double polarised measurement of the A _{x, z} spin correlation parameter in the pN → {pp} _s π process.     

Physics prospects at J-PARC

We have held an inauguration ceremony of the Japan Proton Accelerator Research Complex （JPARC） on July 6,2009,celebrating the completion of its construction.Now,the beam commissioning of the 50 GeV main proton synchrotron is in progress to improve the beam intensity and quality.A lot of important experimental programs in Nuclear Physics are waiting for the beam.In this report,I introduce some examples.     

High pressure studies at the photon factory

Abstract

The Photon Factory has unique features from the point of view of high pressure research. Six beamlines have been used for high pressure experiments, two of which were constructed as dedicated beamlines for large high pressure devices. Various kinds of high pressure studies, such as powder and single crystal x-ray diffraction and absorption experiments, have been carried out on these beamlines by more than 30 user groups, including foreign visitors. Two types of high pressure apparatuses are most frequently used. One is the large volume high pressure devices (MAX80 and MAX90) combined with high energy and/or high brightness synchrotron radiation. The other is a system combining the diamond anvil cell with a 2-dimensional detector, the IMAGE PLATE. Many improvements have been made both in the high pressure techniques and the diffraction measurement methods.

Presented at the IUCr Workshop on ‘Synchrotron Radiation Instrumentation for High Pressure Crystallography’. Daresbury Laboratory 20-21 July 1991     

Investigating bottom-quark Yukawa interaction at Higgs factory

Measuring the fermion Yukawa coupling constants is important for understanding the origin of the fermion masses and their relationship with spontaneously electroweak symmetry breaking.In contrast,some new physics(NP)models change the Lorentz structure of the Yukawa interactions between standard model(SM)fermions and the SM-like Higgs boson,even in their decoupling limit.Thus,the precise measurement of the fermion Yukawa interactions is a powerful tool of NP searching in the decoupling limit.In this work,we show the possibility of investigating the Lorentz structure of the bottom-quark Yukawa interaction with the 125 GeV SM-like Higgs boson for future e^+e^- colliders.     

兰州冷却储存环上可开展的强子物理研究

介绍了当前强子物理的研究现状和兰州冷却储存环的能量特点,以及国内强子物理专家的分析和建议。在兰州冷却储存环上,可利用中能轻离子束核反应产生强子激发态研究强子内部夸克态的结构和性质、强子性质随核环境的变化和手征对称破缺与部分恢复。尤其是通过兰州冷却储存环上限能区附近的P＋P反应,研究奇异夸克的不对称性和形状因子,寻找超子激发态和pentaquark的实验证据,发现双重子态的实验事例。 According to both the development on badrons physics and the aspect of Lanzhou cooling storage ring （CSR） and based on the analysis and propositions given by experts in China, we propose some hadrons physics program at CSR. The hadron spectroscopy produced in light nucleus collisions at CSR used to probe the quark and gluon structure of hadrons, to study the modification of the hadron properties in nuclear matter and to investigate the spontaneous breaking of the chiral symmetry and its partial restoration. Especially, the proton-proton collisions at beam energies per proton below 2.8 GeV at CSR should be used to measure the strangeness asymmetry and strange form lector, to probe the existence of hyperon and pentaquarks and to find the evidence for the existence of dibaryon.     

Physics at the linear collider

The physics at the plannede ⁺ e ^- colliders is discussed around three main topics corresponding to different manifestations of symmetry breaking:W physics in the no Higgs scenario, studies of the properties of the Higgs and precision tests of SUSY. A comparison with the LHC is made for all these cases. The γγ mode of the linear collider will also be reviewed.     

Strangeness Nuclear Physics at J-PARC

After the big earthquake in the east part of Japan on March 11, 2011, the beams in the hadron experimental hall at J-PARC have been successfully recovered in February, 2012. The experimental program using pion beams is now on-going with the primary proton beam power of ~5 kW. Before a long summer shutdown scheduled in 2013, several experiments in strangeness nuclear physics are going to take data. In this period, we anticipate the beam power would exceed 10 kW and the experiments to use K ^? beams will start. The experimental program is explained briefly.