Inclusive jet cross sections and dijet correlations in D photoproduction at HERA
Inclusive jet cross sections in photoproduction for events containing a D ∗ D ∗ meson have been measured with the ZEUS detector at HERA using an integrated luminosity of 78.6 pb −1 78.6 pb −1 . The events were required to have a virtuality of the incoming photon, Q 2 Q 2 , of less than 1 GeV 2 , and a photon–proton centre-of-mass energy in the range 130 γp 130 W γ p 280 GeV . The measurements are compared with next-to-leading-order (NLO) QCD calculations. Good agreement is found with the NLO calculations over most of the measured kinematic region. Requiring a second jet in the event allowed a more detailed comparison with QCD calculations. The measured dijet cross sections are also compared to Monte Carlo (MC) models which incorporate leading-order matrix elements followed by parton showers and hadronisation. The NLO QCD predictions are in general agreement with the data although differences have been isolated to regions where contributions from higher orders are expected to be significant. The MC models give a better description than the NLO predictions of the shape of the measured cross sections.

title: Measurement of prompt photons with associated jets in photoproduction at HERA
abstract: The photoproduction of prompt photons, together with an accompanying jet, has been studied in ep collisions at a centre-of-mass energy of 318 GeV with the ZEUS detector at HERA using an integrated luminosity of 77 pb-1. Cross sections were measured for the transverse energy of the photon and the jet larger than 5 and 6 GeV, respectively. The differential γ+jet cross sections were reconstructed as functions of the transverse energy, pseudorapidity and xγobs, the fraction of the incoming photon momentum taken by the photon-jet system. Predictions based on leading-logarithm parton-shower Monte Carlo models and next-to-leading-order (NLO) QCD generally underestimate the cross sections for the transverse energies of prompt photons below 7 GeV, while the kT-factorisation QCD calculation agrees with the data better. When the minimum transverse energy of prompt photons is increased to 7 GeV, both NLO QCD and the kT-factorisation calculations are in good agreement with the data.

title: Measurement of isolated photons accompanied by jets in deep inelastic ep scattering
abstract: The production of isolated high-energy photons accompanied by jets has been measured in deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 326pb -1 . Measurements were made for exchanged photon virtualities, Q 2 , in the range 10 to 350GeV 2 . The photons were measured in the transverse-energy and pseudorapidity ranges 4 γ jet <1.8. Differential cross sections are presented as functions of these quantities. Perturbative QCD predictions give a reasonable description of the shape of the measured cross sections over most of the kinematic range, but the absolute normalisation is typically in disagreement by 20-30%.

title: Measurement of charged current deep inelastic scattering cross sections with a longitudinally polarised electron beam at HERA
abstract: Measurements of the cross sections for charged current deep inelastic scattering in  collisions with longitudinally polarised electron beams are presented. The measurements are based on a data sample with an integrated luminosity of 175 pb−1 collected with the ZEUS detector at HERA at a centre-of-mass energy of 318 GeV. The total cross section is given for positively and negatively polarised electron beams. The differential cross-sections dσ/dQ2, dσ/dx and dσ/dy are presented for Q2>200 GeV2. The double-differential cross-section d2σ/dxdQ2 is presented in the kinematic range 280<Q2<30 000 GeV2 and 0.015<x<0.65. The measured cross sections are compared with the predictions of the Standard Model.

title: The spectrometer system for measuring ZEUS luminosity at HERA
abstract: The upgrade of the HERA accelerator has provided much increased collider luminosity. In turn, the improvements have necessitated a new design for the ZEUS luminosity measurements. The intense synchrotron radiation field, as well as the high probability of a bremsstrahlung photon in each bunch crossing, posed new experimental constraints. In this report, we describe how these challenges were met with the ZEUS luminosity spectrometer system. The design, testing and commissioning of the device are described, and the results from the initial operational experience are reported.

title: Measurement of azimuthal asymmetries in neutral current deep inelastic scattering at HERA
abstract: The distribution of the azimuthal angle of charged and neutral hadrons relative to the lepton plane has been studied for neutral current deep inelastic ep scattering using an integrated luminosity of 45 pb-1 taken with the ZEUS detector. The kinematic range is 100<Q2<8000 GeV2, 0.2<y<0.8 and 0.01<x<0.1 where Q2 is the virtuality of the exchanged boson, y is the inelasticity and x is the Bjorken variable. The measurements were made in the hadronic centre-of-mass system. The analysis exploits the energy-flow method, which allows the measurement to be made over a larger range of pseudorapidity compared to previous results. The dependence of the moments of the azimuthal distributions on the pseudorapidity and minimum transverse energy of the final-state hadrons are presented. Although the predictions from next-to-leading-order QCD describe the data better than do the Monte Carlo models incorporating leading-logarithm parton showers, they still fail to describe the magnitude of the asymmetries. This suggests that higher-order calculations may be necessary to describe these data.

title: Total Nuclear Reaction Cross Section Induced by Halo Nuclei and Stable Nuclei
abstract: We develop the method for the calculation of the total reaction cross sections induced by the halo nuclei and stable nuclei. This approach is based on the Glauber theory, which is valid for nuclear reactions at high energy. It is extended for nuclear reactions at low energy and intermediate energy by including both the quantum correction and Coulomb correction under the assumption of the effective nuclear density distribution. The calculated results of the total reaction cross section induced by stable nuclei agree well with the 30 experimental data within 10 percent accuracy.The comparison between the numerical results and the 20 experimental data for the total nuclear reaction cross section induced by the neutron halo nuclei and the proton halo nuclei indicates a satisfactory agreement after considering the halo structure of these nuclei, which implies the quite different mean fields for the nuclear reactions induced by halo nuclei and stable nuclei. The halo nucleon distributions and the root mean square radii of these nuclei can be extracted from above comparison based on the improved Glauber model, which indicate clearly the halo structures of these nuclei. Especially, it is clear to see that the medium correction of the nucleon-nucleon collision has little effect on the total reaction cross sections induced by the halo nuclei due to the very weak binding and the very extended density distribution.

title: New Geiger-Nuttall law for alpha decay of heavy nuclei

title: Microscopic calculation of α-decay half-lives within the cluster model
abstract: The α-decay half-lives of heavy and superheavy nuclei are systematically calculated using a radial wave function within the cluster model. The decaying state is considered as an isolated quasi-bound state, and the α-decay process is interpreted as the quantum transition from the quasi-bound state to the scattering state. Then the quasi-bound state wave function and the scattering state wave function, in combination with the difference of potentials, are used to give a clear expression of the α-decay width. The present study is mainly restricted to even–even nuclei with N > 126 , including the superheavy mass region. The obtained α-decay half-lives are found to be in good agreement with the experimental data. Moreover, the study has been extended to the newly observed heaviest nuclei. It is worth noting that the aim of this work is not only to reproduce the experimental data better, but also to extend our understanding of α decay.

title: Liquid-gas phase transition in hot asymmetric nuclear matter
abstract: We use a density-dependent relativistic mean field model to study the properties of nuclear systems at finite temperature. The liquid-gas phase transition of symmetric and asymmetric nuclear matter is discussed. A limiting pressure plim for hot asymmetric nuclear matter has been found because of the density dependence of the nucleon-nucleon-rho meson coupling. It is found that the liquid-gas phase transition cannot take place if p > plim. The binodal surface for this model is addressed. In addition, we calculated the asymmetry parameter dependence of the critical temperature.

title: Theoretical study on neutron skin thickness of Ca isotopes by parity-violating electron scattering
abstract: The parity-violating electron scattering (PVS) experiment of Ca-48 has been proposed in Jefferson Lab recently. In this paper, the relation between neutron radius of Ca-48 and corresponding parity-violating asymmetry A(pv) is investigated. With this relation, we can extract the neutron radius of Ca-48 from measurement at only one single momentum transfer. The statistical error for measuring A(pv) of Ca-48 is also calculated at the kinematics of CREx. Besides, with the study of linear dependence between Delta R-np and L, it enable us to constrain the slope L of the symmetry energy. Parity-violating electron scattering off Ca isotopes is also studied because some experimental errors can be canceled by combining PVS measurements of isotopes. To analyze the differences of neutron skin thickness of Ca isotopes, we fit the mean-field densities with 2pF distributions and study the bulk and surface contributions. By comparing the half density radius and surface parameter along Ca isotopes, we note there may exist neutron halo nuclei in the extreme neutron rich range. Crown Copyright (C) 2013