Hadron multiplicities in the presence of light gluinos

We consider the effect of a massless gluino on the evolution of a parton shower. The hadron multiplicity distribution is predicted to evolve as a function of the collider energy in the same way as in the absence of gluinos, except for a slower running of _s. A comparison of the predicted average hadron multiplicity with experimental data is presented as a fit constraining the values of the strong coupling constant at the Z⁰ peak _s(m_Z) and the scale of the onset of hadronizationm ₀. It appears that light gluinos are unlikely to be detected this way with less than 500 GeV of centre of mass energy.     

Hadron molecules

We discuss a possible interpretation of the open charm mesons D＊s0 （2317）,D s1 （2460） and the hidden charm mesons X（3872）,Y（3940） and Y（4140） as hadron molecules.Using a phenomenological Lagrangian approach we review the strong and radiative decays of the D＊ s0 （2317） and D s1 （2460） states.The X（3872） is assumed to consist dominantly of molecular hadronic components with an additional small admixture of a charmonium configuration.Determing the radiative （γJ/ψ and γψ（2s）） and strong （J/ψ2π and J/ψ3π） decay modes we show that the present experimental observation is consistent with the molecular structure assumption of the X（3872）.Finally,we give evidence for molecular interpretations of the Y（3940） and Y（4140） related to the observed strong decay modes J/ψ＋ω or J/ψ＋φ,respectively.     

Hadron molecules

We discuss a possible interpretation of the open charm mesons D*s0 (2317),D s1 (2460) and the hidden charm mesons X(3872),Y(3940) and Y(4140) as hadron molecules.Using a phenomenological Lagrangian approach we review the strong and radiative decays of the D* s0 (2317) and D s1 (2460) states.The X(3872) is assumed to consist dominantly of molecular hadronic components with an additional small admixture of a charmonium configuration.Determing the radiative (γJ/ψ and γψ(2s)) and strong (J/ψ2π and J/ψ3π) decay modes we show that the present experimental observation is consistent with the molecular structure assumption of the X(3872).Finally,we give evidence for molecular interpretations of the Y(3940) and Y(4140) related to the observed strong decay modes J/ψ+ω or J/ψ+φ,respectively.     

Hadron multiplicities in e<Superscript>+</Superscript>e<Superscript>-</Superscript> annihilation with heavy primary quarks

The multiple hadron production in the events induced by the heavy primary quarks in e⁺e^- annihilation is reconsidered with account of corrected experimental data. A new value for the multiplicity in bb̄ events is presented on the basis of pQCD estimates.     

Transient fission and multiplicities

The de-excitation chain of the compound nucleus is treated, including the transient character of the fission process. The equations can handle all type of emission and take into account all the nuclei of the decay chain. The results show that the particles behave differently under the transient regime.     

Hadron spectroscopy at BABAR

The high integrated luminosity collected by the BABAR detector at the SLAC PEP-II e ⁺ e ^- B-Factory offers an excellent opportunity for the study of heavy-quark spectroscopy. A selection of the most recent results reported by BABAR will be presented, focussing on recently observed states with both open- and hidden-charm content.     

Hadron structure in medium

The quark meson coupling model may be viewed as a natural generalization of QHD which takes into account the internal structure of the nucleon. In such an approach it is natural for the properties of the nucleon to change in medium. We discuss the change in the proton electric and magnetic form factors when it is bound in a specific shell model orbit. Modern quasi-elastic electron scattering experiments should be able to detect effects of the size predicted. We also examine the mean field potential felt by an ω in a finite nucleus, concluding that the ω should be bound by between 50 and 100 MeV.     

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+e-annihilation and the X(3915), Y(4350) states observed in two-photon collisions.     

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 physics with PANDA

The PANDA experiment at the new FAIR facility has a dedicated program of utilizing antiprotons for hadron physics. It belongs to the group of core experiments, which will be realized at the first stages of the facility. PANDA will be a universal detector to study the strong interaction by utilizing the annihilation process of antiprotons with protons and nuclear matter. The past few years have been used by the collaboration to do extensive detector R&D and to sharpen the physics case. This paper gives an introduction into the hadron physics with antiprotons as it is planned with PANDA.     

Hadron accelerators for radiotherapy

Over the last twenty years the treatment of cancer with protons and light nuclei such as carbon ions has moved from being the preserve of research laboratories into widespread clinical use. A number of choices now exist for the creation and delivery of these particles, key amongst these being the adoption of pencil beam scanning using a rotating gantry; attention is now being given to what technologies will enable cheaper and more effective treatment in the future. In this article the physics and engineering used in these hadron therapy facilities is presented, and the research areas likely to lead to substantive improvements. The wider use of superconducting magnets is an emerging trend, whilst further ahead novel high-gradient acceleration techniques may enable much smaller treatment systems. Imaging techniques to improve the accuracy of treatment plans must also be developed hand-in-hand with future sources of particles, a notable example of which is proton computed tomography.     

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 the2008 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 WA102and BNL E852 experiments.     

Hadron production near threshold

Final state interaction effects inpp→ pΛK ⁺ andpd →³Heη reactions are explored near threshold to study the sensitivity of the cross-sections to thepΛ potential and theηN scattering matrix. The final state scattering wave functions between Λ andp andη and³He are described rigorously. The Λ production is described by the exchange of one pion and aK-meson between two protons in the incident channel. Theη production is described by a two-step model, where in the first step a pion is produced. This pion then produces anη by interacting with another nucleon     

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.     

Next-to-leading order corrections to multiplicities

It is desirable to develop a systematic and practical method in perturbative QCD to analyze the semi-hard processes in the fragmentation of jets. In this paper, an integral equation with angular ordering is introduced to analyze the multiplicities of hadrons in high-energy jet productions. In order to demonstrate how the method works, the method is applied in the next-to-leading order to the energy dependence of the multiplicity and to the ratio of multiplicities in a gluon jet and in a quark jet. The results agree with the calculations done by Mueller by a different method.     

高能强子–强子碰撞中硬软过程的比较分析

根据QCD中“圆锥定义”来确定喷注,对高能强子-强子碰撞中的硬、软过程作细致的分析.用Pythia产生蒙特卡罗模拟样本,得到的喷注赝快度分布在中心区有平台,喷注内部的粒子密度和横能密度,随离喷注轴的距离指数地下降,比较发现对整个事件样本,单事件平均横动量或最大横动量与多重数是正关联的,而对喷注事件它们是负关联的.引入两个物理量来描述喷注事件的硬、软程度.发现它们与单事件平均横动量是正关联的,而与多重数是负关联的.表明用单事件平均横动量比用多重数能更好地描述喷注事件的硬软程度.     

强子结构与核结构

本文列举了核内存在非核子自由度的证据;论证了核结构的研究必须突破传统的框架,进入到核子及介子的内部结构,才能对原子核内部运动有深入的了解.本文还扼要论述了核物理研究的现状与前景. This paper presents some important experimental evidences of non-nucleonic degrees of freedom in nuclei.From these evidences,the nuclear structure research must go be- yond the traditional framework of nuclear research.To get deeper understanding of the nucle- us,one has to go to the internal structure of hadrons.The present status and future prospects of this new development in nuclear physics are also dicussed briefly.     

Hadron physics at low energies

Understanding how quantum chromodynamics, the theory of strong interaction, works in the low-energy region, the so-called confinement region is one of the major challenges facing physicists. Low energy hadron physics, particularly the structure of hadron is one of the most active areas of research in nuclear physics addressing this challenge. In this talk, I will review advances made in this area on a few selected topics in the last decade or so and also provide outlook for the future.