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In this article, we review our study of the K−pp, which is a prototype system of kaonic nuclei, with a fully coupled-channel complex scaling method (Full ccCSM). In the present study, i) the K−pp is treated as a resonant state of a K¯NN-πΣN-πΛN coupled-channel system, ii) a chiral SU(3)-based potential as well as a phenomenological potential is examined as a K¯N-πY potential, and iii) property of the K−pp is investigated by analyzing the wave function obtained with the Full ccCSM calculation. It is noted that the energy dependence involved in a chiral SU(3)-based potential is taken into account by considering the self-consistency for the meson-baryon energy. As a result, we have successfully found a resonant pole corresponding to the K−pp on the complex energy plane, and compared it with the latest experimental result reported by J-PARC E15 group. Furthermore, we have considered an energy-fixed case of a chiral SU(3) potential and also the effect of kinematics of mesons by examining the semi-relativistic calculation. [ABSTRACT FROM AUTHOR]

The study of the spectrum and structure of excited nucleon states employing the electroproduction of exclusive reactions is an important avenue for exploring the nature of the non-perturbative strong interaction. The CLAS detector in Hall B has provided the dominant part of the available world data on most relevant meson electroproduction channels off the nucleon in the resonance region for Q2 up to 5 GeV2. Analyses of CLAS data for the exclusive channels πN, ηN, and π+π−p on a proton target have provided the only results available on the Q2 evolution of the electro-excitation amplitudes for the transitions from the initial photon-proton to the final N* states in the mass range up to W =1.8 GeV. These electrocouplings allow for exploration of the internal structure of the produced excited nucleon states. This work has made it clear that consistent results from independent analyses of several exclusive channels with different resonance hadronic decay parameters and non-resonant backgrounds but the same N* electro-excitation amplitudes, is essential to have confidence in the extracted results. Starting in early 2018, a program to study the spectrum and structure of N* states in various exclusive electroproduction channels using the new CLAS12 spectrometer commenced. These studies will probe the structure of N* states in the mass range up to W =3 GeV and for Q2 as low as 0.05 GeV2 and as high as 10-12 GeV2, thus providing a means to access N* structure information spanning a broad range of distance scales. Quasi-real photoproduction studies are also planned to search for additional N* states, the so-called hybrid baryons, for which the glue serves as an active structural component. In this talk the N* programs from both CLAS and CLAS12 will be reviewed. [ABSTRACT FROM AUTHOR]

Motivated by the recent precise SIDDHARTA measurement of the energy shift and width of kaonic hydrogen, we have revisited the theoretical study of the meson-baryon interaction in the S = −1 sector, employing a chiral SU(3) lagrangian up to next-to-leading order (NLO) and implementing unitarization in coupled channels. The parameters of the model have been fitted to a large set of experimental data, paying attention to processes that are especially sensitive to the NLO terms, such as the K−p → K+Ξ−, K0 Ξ0 reactions. Explicit resonant terms have been included to explore their effects on the stability of the low-energy constants and the data description. We have also studied the role of new single isospin reactions and have found them to provide more homogeneous and reliable NLO parameters. We conclude that additional isospin filtering processes, like the K0Lp → K+Ξ−, K0Ξ0 reaction that could be measured at the proposed secondary K0L beam at Jlab, would put valuable constraints on the chiral models describing the S = −1 meson-baryon interaction. [ABSTRACT FROM AUTHOR]

The simplest form of the Hyperfine Interaction (HFI) of quarks is a color-spin interaction, sometimes called Fermi-Breit (FB) HFI. For conventional hadrons, this HFI for quark-antiquark (qq̄) pairs is twice as strong as the same HFI for quark-quark (qq or q̄q̄) pairs, but this difference is absorbed into the different HFI constants for mesons and baryons, which are free parameters of the fits. For tetraquarks, however, qq̄ HFI is only half as strong as the qq/q̄q̄ HFI and both kinds of pairs coexist within the same state. Hence it is worth investigating a model with different fit constants for qq̄ and qq/q̄q̄ pairs. We have investigated 3 models of spin-color HFI for light scalar tetraquarks: 2 models with single constants for both kinds of pairs and one model with different fit constants. The light scalar nonet is chosen because of a lack of other experimentally observed multiplets interpretable as pure exotic states. Since even the nonet contains only 3 particles with distinct masses (i. e. 3 fit points), the constituent quark masses had to be taken from conventional hadron fits obtained in our previous work. The two-constant model did not prove to be a viable alternative to the one-constant models. [ABSTRACT FROM AUTHOR]

From a brief recapitulation of the foundational works of Marius Sophus Lie and Herrmann Günther Grassmann, and including missing African links, a rhapsodic survey is made of the straight line of extension and existence that runs as the very fibre of generation and creation throughout Nature's all utterances, which must therefore ultimately be the web of Reality itself of which the Arts and Sciences are interpreters on equal explorer terms. Assuming their direct approach, the straight line and its archaic and algebraic and artistic bearings and convolutions have been followed towards their inner reaches, which earlier resulted in a retrieval of the baryon and meson elementary particles and now equally straightforward the electron geodesics and the organic build of the periodic system of the elements. [ABSTRACT FROM AUTHOR]

The Λ(1405) baryon is difficult to detect in experiment, absent in many quark model calculations, and supposedly manifested through a two-pole structure. Its uncommon properties made it subject to numerous experimental and theoretical studies in recent years. Finite-volume Lattice-QCD eigenvalues for different quark masses were recently reported by the Adelaide group. We compare these eigenvalues to predictions of a model based on Unitary Chiral Perturbation Theory (UCHPT). The UCHPT calculation predicts the quark mass dependence remarkably well. It also explains the overlap pattern with different meson-baryon components, mainly πΣ and K¯ N, at different quark masses. More accurate Lattice QCD data are required to draw definite conclusions on the nature of the Λ(1405). [ABSTRACT FROM AUTHOR]

In these proceedings some facts about resonances are discussed focusing on the analytic properties of resonant amplitudes with special emphasis on model independent analyses. As an illustrative example of the latter point the decays Bd/s→ J/ψ ππ are discussed in some detail. [ABSTRACT FROM AUTHOR]

We present a calculation of the Hadron spectrum in the Dyson-Schwinger/Bethe-Salpeter approach to continuum QCD. A sophisticated truncation featuring all covariant structures of the quark-gluon vertex, with its inherent flavour dependence, is employed in a framework that preserves the dynamics of chiral symmetry breaking. The study is suggestive as to the relevance of additional resonant and non-resonant two- and three-body contributions. [ABSTRACT FROM AUTHOR]

The spectrum of excited hadrons - mesons and baryons - serves as an excellent probe of quantum chromodynamics (QCD), the fundamental theory of the strong interaction. The strong coupling however makes QCD challenging. It confines quarks and breaks chiral symmetry, thus providing us with the world of light hadrons. Highly-excited hadronic states are sensitive to the details of quark confinement, which is only poorly understood within QCD. This is the regime of nonperturbative QCD and it is one of the key issues in hadronic physics to identify the corresponding internal degrees of freedom and how they relate to strong coupling QCD. The quark model suggests mesons are made of a constituent quark and an antiquark and baryons consist of three such quarks. QCD predicts other forms of matter. What is the role of glue? Resonances with large gluonic components are predicted as bound states by QCD. The lightest hybrid mesons with exotic quantum numbers are estimated to have masses in the range from 1 to 2 GeV/c2 and are well in reach of current experimental programs. At Jefferson Laboratory (JLab) and other facilities worldwide, the high-energy electron and photon beams present a remarkably clean probe of hadronic matter, providing an excellent microscope for examining atomic nuclei and the strong nuclear force. [ABSTRACT FROM AUTHOR]

We present a calculation of the Hadron spectrum in the Dyson-Schwinger/Bethe-Salpeter approach to continuum QCD. A sophisticated truncation featuring all covariant structures of the quark-gluon vertex, with its inherent flavour dependence, is employed in a framework that preserves the dynamics of chiral symmetry breaking. The study is suggestive as to the relevance of additional resonant and non-resonant two- and three-body contributions. [ABSTRACT FROM AUTHOR]

The spectrum of excited hadrons - mesons and baryons - serves as an excellent probe of quantum chromodynamics (QCD), the fundamental theory of the strong interaction. The strong coupling however makes QCD challenging. It confines quarks and breaks chiral symmetry, thus providing us with the world of light hadrons. Highly-excited hadronic states are sensitive to the details of quark confinement, which is only poorly understood within QCD. This is the regime of nonperturbative QCD and it is one of the key issues in hadronic physics to identify the corresponding internal degrees of freedom and how they relate to strong coupling QCD. The quark model suggests mesons are made of a constituent quark and an antiquark and baryons consist of three such quarks. QCD predicts other forms of matter. What is the role of glue? Resonances with large gluonic components are predicted as bound states by QCD. The lightest hybrid mesons with exotic quantum numbers are estimated to have masses in the range from 1 to 2 GeV/c² and are well in reach of current experimental programs. At Jefferson Laboratory (JLab) and other facilities worldwide, the high-energy electron and photon beams present a remarkably clean probe of hadronic matter, providing an excellent microscope for examining atomic nuclei and the strong nuclear force. [ABSTRACT FROM AUTHOR]

We briefly review the generalized Skyrmion model for the baryon recently suggested by us. It takes into account the tower of vector and axial mesons as well as the chiral symmetry breaking. The generalized Skyrmion model provides the qualitative explanation of the Ioffe's formula for the baryon mass. [ABSTRACT FROM AUTHOR]

I present some recent results regarding the use of numerical Lattice QCD techniques to describe light nuclear systems from the underlying theory of the strong interaction, QCD. [ABSTRACT FROM AUTHOR]

We report on hadron spectroscopy using the CLAS at Jefferson Lab. We present preliminary results from photoproduction experiments studying the spectroscopy of exotic mesons, cascades (Ξ's) and Dalitz decays of pseudo-scalar mesons in the largest data sample ever to be produced at photon energies of about 5 GeV. We also describe, briefly, a new experiment to continue hadron spectroscopy at CLAS12 (at Jefferson Lab energy upgrade) using electroproduction at very low Q2 ("quasireal photons") up to photon energies of 10 GeV. [ABSTRACT FROM AUTHOR]

One of the most challenging topics in Quantum Chromo-Dynamics (QCD) for decades is the study of nucleon structure in terms of the fundamental QCD picture of quarks and gluons. Performing this study over a range of energies helps understand the dynamics of strong interaction, and gives a reasonable description of the transition from colored confined partons to the ordinary colorless hadrons. One of the best tools to study this transition is to search for the onset of Color Transparency (CT), one of the predicted phenomena of QCD. Color transparency refers to the suppression of final (and/or initial) state interactions caused by the cancellation of color fields in a special configuration of quarks and gluons with small transverse separation. I will give an overview of the CT measurements that were carried through the production of different hadrons at various energies, and highlight the future experiments planned for the 12 GeV upgrade at Jefferson Lab. [ABSTRACT FROM AUTHOR]

The spectrum of excited baryons serves as an excellent probe of quantum chromodynamics (QCD). In particular, highly-excited baryon resonances are sensitive to the details of quark confinement which is only poorly understood within QCD. Facilities worldwide such as Jefferson Lab, ELSA, and MAMI, which study the systematics of hadron spectra in photo- and electroproduction experiments, have accumulated a large amount of data in recent years including unpolarized cross section and polarization data for a large variety of meson-production reactions. These are important steps toward complete experiments that will allow us to unambiguously determine the scattering amplitude in the underlying reactions and to identify the broad and overlapping baryon resonance contributions. Several new nucleon resonances have been proposed and changes to the baryon listing in the 2012 Review of Particle Physics reflect the progress in the field. [ABSTRACT FROM AUTHOR]

We calculate the η′ amplitude at low energies considering chiral Lagrangians and η η′ mixing, the coupling of η′N to the victor-baryon channels and one Lagrangian allowed for singlet meson-baryon interaction. We obtain cross sections for elastic η′ scattering and transition of η′N to the open channels πN, ηN, η′N, KΛ and KΣ. [ABSTRACT FROM AUTHOR]

Elastic πN scattering and the related reactions πN→KΛ, KΣ are described simultaneously in a unitary coupled-channel approach which respects analyticity and other general properties of the S-matrix. SU(3) flavor symmetry is used to relate the t- and u- channel exchanges that dirve the meson-baryon interaction in the different channels. [ABSTRACT FROM AUTHOR]

A Dyson-Schwinger equation calculation of the light hadron spectrum, which correlates the masses of meson and baryon ground- and excited-states within a single framework, produces a description of the Roper resonance that corresponds closely with conclusions drawn recently by EBAC. Namely, the Roper is a particular type of radial excitation of the nucleon's dressed-quark core augmented by a material meson cloud component. There are, in addition, some surprises. [ABSTRACT FROM AUTHOR]

An overview of current theoretical approaches to generate meson-baryon reaction amplitudes is given. [ABSTRACT FROM AUTHOR]

In this opening talk at MENU2010 we outline some of the key achievements in the field over the past few years as well as some of its major challenges and opportunities. [ABSTRACT FROM AUTHOR]

We analyze meson-baryon scattering lengths in the framework of covariant baryon chiral perturbation theory at leading one-loop order. We compute the complete set of matching relations between the dimension-two low-energy constants in the two- and three-flavor formulations of the theory. We derive new two-flavor low-energy theorems for pion-hyperon scattering that can be tested in lattice simulations. [ABSTRACT FROM AUTHOR]

Meson-baryon scattering and photon-nucleon reactions are described in a coupled-channel approach for energies below 2 GeV. Poles and residues of the reaction amplitudes are obtained by analytical continuation. The dependence of the resonance poles on the pion mass is investigated. [ABSTRACT FROM AUTHOR]

Elastic πN scattering and the reaction π+p→K+Σ+ are described simultaneously in a unitary coupled-channels approach which respects analyticity. SU(3) flavor symmetry is used to relate the t- and u- channel exchanges that drive the meson-baryon interaction in the different channels. Angular distributions, polarizations, and spin-rotation parameters are compared with available experimental data. The pole structure of the amplitudes is extracted from the analytic continuation. [ABSTRACT FROM AUTHOR]

We present the current status of a combined and simultaneous analysis of meson production reactions based on a dynamical coupled-channels (DCC) model, which is conducted at Excited Baryon Analysis Center (EBAC) of Jefferson Lab. [ABSTRACT FROM AUTHOR]

The latest results on B hadron spectroscopy from the DO\ experiment at the Tevatron are presented. The mass measuremen of the Bc- meson in the Bc-→J/ψπ- decay channel, the observation of excited Bs mesons, the first direct observation of the Ξb- baryon, and the first observation of the Ωb- baryon. [ABSTRACT FROM AUTHOR]

We demonstrate the equivalence of the light-front, equal-time and covariant formulations in meson-baryon interactions. In particular, we discuss the self-energy Σ of a nucleon dressed by pion loops with the pseudovector πNN coupling. It is shown that the leading nonanalytic behavior of Σ is equivalent whichever formulations are used for the derivation. [ABSTRACT FROM AUTHOR]

We overview a holographic QCD based on the D4-D8 string theory model, with emphasis on baryons and nucleon-meson interactions thereof. Baryons are realized as holographic images of Skyrmions, but with much qualitative changes. This allows us to derive, without adjustable parameters, couplings of baryons to the entire tower of spin one mesons and also to pseudoscalar mesons. We find some surprisingly good match against empirical values for nucleons, in particular. Tensor couplings to all axial-vectors and iso-singlet vectors all vanish, while, for ρ mesons, tensor couplings are found to be dominant. We close with various cautionary comments and speculations. [ABSTRACT FROM AUTHOR]

The negative-parity charmed baryons are investigated by employing the quark model as well as the effective baryon meson model with a bound state embedded in the continuum. Especially the mass difference between the JP = 1/2- and 3/2-Λc+ baryons is discussed. The observed value of this mass splitting is almost the same as that of Ξc, about 30 MeV. It is found that most of this splitting can be reproduced by assuming a simple qqQ configuration. The coupling to the baryon-meson scattering state may enlarge the splitting as it does for the Λ(1405)(1/2-) and Λ(1520)(3/2-) case. We investigate this coupling effect and find that with an appropriately modified coupling or the pole energy, the peak can be reproduced. [ABSTRACT FROM AUTHOR]

We report the current status of exploring the dynamical aspect of the excited nucleon states through the comprehensive coupled-channels analysis of meson production reactions at the Excited Baryon Analysis Center of Jefferson Lab. [ABSTRACT FROM AUTHOR]

We consider the problem of construction of a spectral representation for nucleon to meson transition distribution amplitudes (TDAs), non-diagonal matrix elements of nonlocal three quark operators between a nucleon and a meson states. We introduce the notion of quadruple distributions and generalize Radyshkin's factorized Ansatz for this issue. Modelling of baryon to meson TDAs in the complete domain of their definition opens the way to quantitative estimates of cross-sections for various hard exclusive reactions. [ABSTRACT FROM AUTHOR]

We provide a glimpse of recent progress in hadron physics made using QCD's Dyson-Schwinger equations, reviewing: the notion of in-hadron condensates and a putative solution of a gross problem with the cosmological constant; the dynamical generation of quark anomalous chromo- and electro-magnetic moments, and their material impact upon the proton's electric/magnetic form factor ratio; a computation that simultaneously correlates the masses of meson and baryon ground- and excited-states; and a prediction for the x→1 value of the ratio of neutron/proton distribution functions. [ABSTRACT FROM AUTHOR]

The gluon action density in a static mesonic system is analyzed at finite temperature using lattice QCD techniques in quenched QCD. The obtained results are compared to predictions of bosonic string models for the flux-tube profiles to understand the changes of the flux-tube profiles with temperature. The mesonic flux tube curved-width profile is found to compare well with that of the bosonic string at large distances. In the intermediate distance region, a free bosonic string behaviour is observed for analysis performed on highly UV-filtered gauge configurations. Extending the analysis to the static baryon reveals a delocalization of the baryonic node in the Y-shape gluonic configuration observed at zero temperature. At finite temperature, a filled delta-shaped configuration is observed, even at large distances. We study a baryonic string model at finite temperature. [ABSTRACT FROM AUTHOR]

We use chirally motivated effective meson-baryon potentials to describe the low energy KN data including the characteristics of kaonic hydrogen. Our results are examined in comparison with other approaches based on the unitarity and dispersion relation for the inverse of the T-matrix. We demonstrate that the movements of the poles generated by the model upon varying the model parameters can serve as a tool to get additional insights on the dynamics of the strongly coupled πΣ-KN system. [ABSTRACT FROM AUTHOR]

We evaluate the pseudoscalar-meson coupling constants and the strangeness-conserving and the strangeness-changing axial charges of octet baryons in lattice QCD with two flavors of dynamical quarks. We find that the coupling constants and the axial charges have rather weak quark-mass dependence and the breaking in SU(3)-flavor symmetry is small at each quark-mass point we consider. [ABSTRACT FROM AUTHOR]

We investigate the scattering of heavy-light K and D mesons by nucleons at low energies. The short-distance part of the interaction is described by quark-gluon interchange and the longdistance part is described by a one-meson-exchange model that includes the contributions of vector (ρ, ω) and scalar (σ) mesons. The microscopic quark model incorporates a confining Coulomb potential extracted from lattice QCD simulations and a transverse hyperfine interaction consistent with a finite gluon propagator in the infrared. The derived effective meson-nucleon potential is used in a Lippmann-Schwinger equation to obtain s-wave phase shifts. Our final aim is to set up a theoretical framework that can be extended to finite temperatures and baryon densities. [ABSTRACT FROM AUTHOR]

We discuss the recent progress in calculating the properties of ‘hybrid stars’ (stellar objects similar to neutron stars, classified by the incorporation of non-nucleonic degrees of freedom, including but not limited to hyperons and/or a quark-matter core) using the octet-baryon Quark-Meson Coupling (QMC) model. The version of QMC used is a recent improvement which includes the in-medium modification of the quark-quark hyperfine interaction. [ABSTRACT FROM AUTHOR]

We discuss the physics of Bs0 mesons focusing on CP violation in Bs0→J/ψ[lowercase_phi_synonym] decays at the Tevatron. We summarize measurements of the properties of bottom baryons at the Tevatron including the Σb states and the Ξb- baryon. We also discuss the discovery of the Ωb- baryon. [ABSTRACT FROM AUTHOR]

Leading neutron production measurements from the H1 and ZEUS experiments at HERA are presented and compared to models. Standard string fragmentation models do not describe the data. Models including also baryon production via virtual meson exchange and accounting for absorption give a good description of the data. In the exchange picture, leading neutron data are used to extract the pion structure function. [ABSTRACT FROM AUTHOR]

Quark models with potentials derived from QCD, including the quark-diquark model for excited hadrons leading to a symmetry between mesons and baryons gives mass formulae in very good agreement with experiment and goes a long way in explaining the approximate symmetries and supersymmetries of the hadronic spectrum, including the symmetry breaking mechanism. We give a description of the only algebra describing color degrees of freedom based on split octonionic units and leading to a mathematical understanding of formation of diquarks as well as multiquark states. [ABSTRACT FROM AUTHOR]

Understanding quark and gluon confinement in Quantum Chromodynamics is one of the main issue in hadronic physics. Electromagnetic probes, real and virtual photons, are a powerful tool to investigate how the QCD-partons manifest themselves in strong interaction at the energy scale of the nucleon mass (GeV). The CLAS Collaboration in Hall B at Jefferson Lab (USA) has a broad scientific program ranging from the static and dynamic properties of constituent quarks to the investigation of possible exotic baryon configurations. After a brief description of the CLAS detector, some selected results will be outlined showing the richness of this non-perturbative physics. [ABSTRACT FROM AUTHOR]

In this work, the strong coupling constants of the octet baryons to the K and π mesons are studied within the Light Cone QCD sum rule method. It is well known that in the SU(3)f limit, these couplings can be expressed in terms of only 2 constants, so called F and D constants. In this work, the SU(3)f symmetry violating effects are also studied and it is shown that all the coupling constants can be expressed in terms of four analytical functions of the quark parameters. [ABSTRACT FROM AUTHOR]

The process of secondary baryon production in π±p collisions at high energies in the central and forward fragmentation regions is considered in the framework of the Quark-Gluon String Model. The contribution of the string-junction mechanism to the baryon production is analysed. The results of numerical calculations are in reasonable agreement with the experimental data on the Λ/A and p/p asymmetries. [ABSTRACT FROM AUTHOR]

Recent studies concerning charmed baryon spectroscopy, performed by the Belle collaboration, are briefly described. We report the first observation of two new baryons [cap_xi]cx(2980) and [cap_xi]cx(3077), a precise determination of the masses of [cap_xi]c(2645) and [cap_xi]c(2815), observation of the Λc(2940)+ and experimental constraints on the possible spin-parity of the Λc(2880)+. Observations of several exclusive decays of B mesons to the final states containing charmed baryons are also briefly presented. © 2007 American Institute of Physics [ABSTRACT FROM AUTHOR]

Recent results in the areas of hypernuclear physics, exotic atoms, photo- and electro-production of light mesons and baryons, and medium modifications of meson properties were presented at this conference. Facility highlights presentations were given for five laboratories: the ELSA complex at Bonn, the LEPS facility at SPring-8, the CLAS facility at Jefferson Lab, the MAMI complex at Mainz, and the COSY complex at Jülich. These talks collectively showed remarkably active programs at all these laboratories, as well as at BNL, KEK, PSI, and Frascati. No “brand new” results were reported at this conference. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

One of the foremost challenges in hadron physics is to obtain an understanding of the effective degrees of freedom which lead to the formation of mesons and baryons and govern their inner structure. The ELSA facility of the university of Bonn provides essential tools to investigate the baryon mass spectrum up to high excitations through the systematic study of single and multiple meson production. This comprises a 3.5 GeV electron accelerator, highly polarized nucleon targets and a 4π spectrometer for charged and neutral particle detection. In this contribution an overview on the instrumentation and the program is given. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The production of baryon and mesons in the RHIC heavy-ion experiments has received a lot of attention lately. Although not widely known, the pp data measured concurrently with heavy ion collisions do not find a convincing explanation in terms of simple models. We present the results of an afterburner to Pythia and Hijing event generators, simulating radial flow which seems to qualitatively explain the experimental results when applied to the pp collision data from RHIC at 200 GeV center-of-mass energy. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The Cronin effect is studied with identified particle spectra from 200GeV d+Au collision at RHIC. The nuclear modification factor RdAu of baryons (proton etc.) rise faster than those of mesons (pions, kaons and phi etc.) and show a baryon/meson scaling behavior similar to that found at Au+Au collisions at same energy. The particle-species dependence of the Cronin effect is observed to be significantly smaller than that at lower energies. The eta asymmetry is also reported and shows contrary trends to prediction based on initial multiple parton scattering model. These measurements indicate that the final state effect plays an important role in the Cronin effect. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Identified particle measurements in 200 GeV Au+Au and d+Au collisions in STAR are presented. The importance of using identified particles to probe properties of medium formed at RHIC is emphasized. Magnitude of the nuclear modification factor is observed to depend on particle type (baryon vs meson) instead of particle mass at intermediate transverse momentum. This observation supports recombination/coalescence processes as dominant dynamics for particle production in this transverse momentum region. We argue that [lowercase_phi_synonym] and heavy quark yields are sensitive to the medium properties at the early stage. The significant suppression of identified particle production observed at high transverse momentum in central Au+Au collisions indicates the formation of strongly-interacting medium at RHIC. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

A combined analysis of new π0 and η photoproduction data from CB-ELSA collaboration was performed including the earlier data from SAID data base, new data on beam asymmetry from the GRAAL collaboration and data on γp → KΛ and KΣ. Three baryon resonances have a substantial coupling to ηN, the well known N(1535)S11, N(1720)P13 and the newly observed N(2070)D15 resonance. A new P11 state with mass 1840 MeV and width 140 MeV was observed contributing to most of the fitted reactions. The data also demand the presence of two D13 states at 1870 and 2170 MeV. The properties of observed states and their contributions to different observables are discussed. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]