Hadron program at COMPASS

The fixed target COMPASS experiment at CERN offers the opportunity to search for exotic mesons and glueball candidates in the light quark sector with unprecedented statistics.Preliminary results from the 2008 data taken with an incoming negative hadron beam （190 GeV/c,mainly pions） on a liquid hydrogen target are presented.New detectors dedicated to hadron beam measurements have been added.These give access to rare neutral and kaonic channels.An amplitude analysis which will allow to fit simultaneously diffractively and/or centrally produced resonances will be described and compared with those used in the CERN WA102 and BNL E852 experiments.     

Hadron spectroscopy from B-factories

We review the recent experimental results on hadron spectroscopy from B-factories focusing on the exotic charmonium-like states.Among them we discuss the X（3872）,Y（3940）,Z（4430） ＋,Z（4050） ＋,Z（4250） ＋ and Y（4140） states found in B-meson decays,the X（3940） and X（4160） states produced in double charmonium production,the Y（4260）,Y（4325）,Y（4660） and X（4630） states produced with initial-state radiation in e ＋ eannihilation and the X（3915）,Y（4350） states observed in two-photon collisions.     

Recent BES results on hadron spectroscopy

Light hadron spectroscopy is a powerful tool in hadronic physics.Several recent BES results on hadron spectroscopy are reported in this proceeding,including the confirmation of the enhancement in pp invariant mass in radiative J/ψ decays,the observation of a charged κ ± decaying to K ± π 0 and the measurement of exclusive decays of the χ c0 and χ c2 to π ^0 π^ 0 and ηη.     

Spectrum of b-baryons: color hyperfine interaction vs. experiment

I discuss several recent highly accurate theoretical predictions for masses of baryons containing the b quark,especially Ωb （ssb） very recently reported by CDF.I also point out an approximate effective supersymmetry between heavy quark baryons and mesons and provide predictions for the magnetic moments of Λc and Λb .Proper treatment of the color-magnetic hyperfine interaction in QCD is crucial for obtaining these results.     

New exotic charmonium states

In the last years many states in the charmonium mass region were discovery by BABAR,Belle and CDF collaborations.I discuss some of these discoveries,and how the QCD Sum Rule approach can be used to understand the structure of these states.     

Holographic models of the scalar sector of QCD

We investigate the AdS/QCD duality for the two-point correlation functions of the lowest dimension scalar meson and scalar glueball operators,in the case of the Soft Wall holographic model of QCD.Masses and decay constants as well as gluon condensates are compared to their QCD estimates.In particular,the role of the boundary conditions for the bulk-to-boundary propagators is emphasized.     

Heavy quark spin symmetry and heavy flavor hadronic molecules

We argue that the heavy quark spin symmetry can lead to important consequences for heavy flavor hadronic molecules.It can be used to predict new heavy flavor hadronic molecules and hence provides a method to identify the nature of some newly observed exotic hadrons.For example,if the Y（4660） were an S-wave ψ f 0 （980） shallow bound state,then the mass,width and line shape of its spin partner are predicted.     

Prospectives of the hadron program in ATLAS

One of the first measurements that will be made at the LHC by ATLAS deals with the properties of inelastic collisions,namely the central charged particle density and transverse momentum distributions.Current predictions of these distributions have large uncertainties in the LHC energy range.We describe the ATLAS minimum bias triggers,designed to select all kind of inelastic interactions,and the performance of the track reconstruction software which was adapted to soft particle track reconstruction.The precision with which the minimum bias distributions can be measured with early data is presented and the uncertainties on the inelastic distributions due to trigger bias is discussed.     

Measurement of PV asymmetry in n＋p→d＋γ and γ＋d→n＋p

The measurement of parity-violating （PV） observables in few-nucleon system can shed light on our current understanding of the weak interaction between nucleons.Theoretical models describe the nucleonnucleon weak interaction at low energies use a series of undetermined parameters.Two parity violating measurements have been considered： the capture of polarized slow neutrons on hydrogen （n ＋ p → d ＋ γ） at Los Alamos National Laboratory for first phase and Oka Ridge National Laboratory for second phase and the helicity dependence of the deuteron photodisintegration cross section using circularly polarized photons （γ ＋ d → n ＋ p） at Shanghai Institute of Applied Physics.The goal of both experiments is to constraint the weak meson-nucleon couplings to a precision of 1 ×10^-8 .The introduction of both experiments is presented.     

Entanglement in a two-qubit Heisenberg XXZ chain with different Dzyaloshinskii-Moriya couplings and an inhomogeneous magnetic field

Ground state entanglement and thermal entanglement of a two-qubit Heisenberg XXZ chain in the presence of the different Dzyaloshinski-Moriya interaction and inhomogeneous magnetic field are investigated.By the concept of concurrence,we find that the inhomogeneity of the magnetic field may make entanglement last for a long time and the critical temperature is dependent on Jz and b.The entanglement can be increased by increasing the temperature in some cases.We also find that the x-component parameter Dx has a higher critical temperature and more entanglement for a certain condition than the z-component parameter Dz.     

Search for new physics in the B→K^（＊）l^＋l^- decays at BABAR

Based on a data sample of 384 million BB pairs collected with the BABAR detector at the PEP-Ⅱ asymmetric e ＋ e ￣ storage ring,we measure branching fractions,direct CP,isospin and lepton-flavor asymmetries for the rare decays B → K （＊） l ＋ l￣ in two di-lepton mass bins above and below the J/ψ resonance.For the B → K＊ l ＋ l￣ decay,we also measure the K＊ longitudinal polarization fraction and the di-lepton forwardbackward asymmetry.     

Preliminary study of a niobium quarter-wave prototype cavity for a heavy-ion superconducting linac

Superconducting quarter-wave resonators,due to their compactness and their convenient shape for tuning and coupling,are very attractive for low-β beam acceleration.In this paper,two types of cavities with different geometry have been numerically simulated the first type with larger capacitive load in the beam line and the second type of lollipop-shape for 100 MHz,β=0.06 beams then the relative electromagnetic parameters and geometric sizes have been compared.It is found that the second type,whose structural design is optimized with the conical stem and shaping drift-tube,can support the better accelerating performance.At the end of the paper,some structural deformation effects on frequency shifts and appropriate solutions have been discussed.     

Supersymmetric contributions to B_s → K~-π~＋ decay

Recently,the CDF Collaboration has measured the branching fraction and time-integrated direct CP asymmetry of Bs → K-π＋ decay.The branching ratio is lower than the previous predictions based on QCD factorization.The experimental results favor a large CP asymmetry in Bs → K-π＋ decay while the standard model prediction is very small.We compute the supersymmetry contributions to Bs → K-π＋ decay using the mass insertion method,and find that the LR and RL mass insertions could suppress this branching ratio and increase this direct CP asymmetry well in line with the experimental data.     

Quark-clustering in cold quark matter

Quarks are proposed to be grouped together to make quark-clusters due to the strong interaction in cold quark matter at a few nuclear densities,because a weakly coupling treatment of the interaction between quarks there would be inadequate.Cold quark matter is then conjectured to be in solid state （i.e.,forming a crystal structure） if the inter-cluster potential is deep enough to localize clusters in lattice.Such a solid state of cold quark matter would be very necessary for us to understand different manifestations of pulsar-like compact stars,and could not be ruled by first principles.     

Hard-thermal-loop QED thermodynamics

The weak-coupling expansion for thermodynamic quantities in thermal field theories is poorly convergent unless the coupling constant is tiny.We discuss the calculation of the free energy for a hot gas of electrons and photons to three-loop order using hard-thermal-loop perturbation theory （HTLpt）.We show that the hard-thermal-loop perturbation reorganization improves the convergence of the successive approximations to the QED free energy at large coupling,e ～ 2.The reorganization is gauge invariant by construction,and due to the cancellations among various contributions,we obtain a completely analytic result for the resummed thermodynamic potential at three loops.     

High pt and photon physics with ALICE at LHC

ALICE,A Large Ion Collider Experiment,is dedicated to study the QCD matter at extreme high temperature and density to understand the Quark Gluon Plasma （QGP） and phase transition.High-transversemomentum photons and neutral mesons from the initial hard scattering of partons can be measured with ALICE calorimeters,PHOS （PHOton Spectrometer） and EMCAL （ElectroMagnetic CALorimeter）.Combing the additional central tracking detectors,the γ-jet and π 0-jet measurements thus can be accessed.These measurements offer us a sensitive tomography probe of the hot-dense medium generated in the heavy ion collisions.In this paper,high p T and photon physics is discussed and the ALICE calorimeters capabilities of high-transverse-momentum neutral mesons and γ-jet measurements are presented.     

A Particle-in-cell scheme of the RFQ in the SSC-Linac

A 52 MHz Radio Frequency Quadrupole （RFQ） linear accelerator （linac） is designed to serve as an initial structure for the SSC-Linac system （injector into Separated Sector Cyclotron）.The designed injection and output energy are 3.5 keV/u and 143 keV/u,respectively.The beam dynamics in this RFQ have been studied using a three-dimensional Particle-In-Cell （PIC） code BEAMPATH.Simulation results show that this RFQ structure is characterized by stable values of beam transmission effciency （at least 95%） for both zerocurrent mode and the space charge dominated regime.The beam accelerated in the RFQ has good quality in both transverse and longitudinal directions,and could easily be accepted by Drift Tube Linac （DTL）.The effect of the vane error and that of the space charge on the beam parameters have been studied as well to define the engineering tolerance for RFQ vane machining and alignment.     

Challenges in uncovering the origin of the proton's spin

One of the most fascinating challenges facing modern strong interaction physics is to understand the origin of the spin of the nucleon in terms of the spin and orbital angular momentum of the quarks and gluons.We review recent progress on this problem as well as some of the uncertainties associated with state of the art lattice QCD simulations.In particular,we explain the importance of the corrections associated with chiral extrapolation and finite volume corrections,especially for the term B（0） extracted from the appropriate low moment of the deeply virtual Compton scattering amplitude.     

Search for the origin of double-peak structure at RHIC by AMPT model with triggered di-jet

With a multi-phase transport （AMPT） model,a γ-jet with known production point and momentum is triggered to search for the origin of double-peak structure in di-hadron azimuthal correlation in central Au＋Au collisions at RHIC energy.The different configurations of triggered γ-jet produce different shapes of medium responses.The key of the double-peak structure is found to be a strong shadowing effect of dense core,which is related to transverse expansion and radial flow of partonic matter.