Abstract: Prompt photon production in root S-NN = 2.76-TeV Pb + Pb collisions has been measured by the ATLAS experiment at the Large Hadron Collider using data collected in 2011 with an integrated luminosity of 0.14 nb(-1). Inclusive photon yields, scaled by the mean nuclear thickness function, are presented as a function of collision centrality and transverse momentum in two pseudorapidity intervals, vertical bar eta vertical bar < 1.37 and 1.52 <= vertical bar eta vertical bar < 2.37. The scaled yields in the two pseudorapidity intervals, as well as the ratios of the forward yields to those at midrapidity, are compared to the expectations from next-to-leading-order perturbative QCD (pQCD) calculations. The measured cross sections agree well with the predictions for proton-proton collisions within statistical and systematic uncertainties. Both the yields and the ratios are also compared to two other pQCD calculations, one which uses the isospin content appropriate to colliding lead nuclei and another which includes nuclear modifications to the nucleon parton distribution functions.

Abstract: Using the Double Chooz detector, designed to measure the neutrino mixing angle theta(13), the products of mu(-) capture on C-12, C-13, N-14, and O-16 have been measured. Over a period of 489.5 days, 2.3 x 10(6) stopping cosmic mu(-) have been collected, of which 1.8 x 10(5) captured on carbon, nitrogen, or oxygen nuclei in the inner detector scintillator or acrylic vessels. The resulting isotopes were tagged using prompt neutron emission (when applicable), the subsequent beta decays, and, in some cases, beta-delayed neutrons. The most precise measurement of the rate of C-12(mu(-), nu)B-12 to date is reported: 6.57(-0.21)(+0.11) x 10(3) s(-1), or (17.35(-0.59)(+0.35))% of nuclear captures. By tagging excited states emitting gamma s, the ground state transition rate to B-12 has been determined to be 5.68(-0.23)(+0.14) x 10(3) s(-1). The heretofore unobserved reactions C-12(mu(-), nu alpha)Li-8, C-13(mu(-), nu n alpha)Li-8, and C-13(mu(-), nu n)B-12 are measured. Further, a population of beta n decays following stopping muons is identified with 5.5 sigma significance. Statistics limit our ability to identify these decays definitively. Assuming negligible production of He-8, the reaction C-13(mu(-), nu alpha)Li-9 is found to be present at the 2.7 sigma level. Limits are set on a variety of other processes.

Abstract: We investigate the possibility of probing the hot and dense nuclear matter-created in relativistic heavyion collisions (HICs)-with strange vector mesons (K*, (K) over bar*). Our analysis is based on the nonequilibrium parton-hadron-string dynamics (PHSD) transport approach which incorporates partonic and hadronic degrees of freedom and describes the full dynamics of HIC on a microscopic level-starting from the primary nucleon-nucleon collisions to the formation of the strongly interacting quark gluon plasma (QGP), followed by dynamical hadronization of (anti)quarks as well as final hadronic elastic and inelastic interactions. This allows us to study the K* and (K) over bar* meson formation from the QGP as well as the in-medium effects related to the modification of their spectral properties during the propagation through the dense and hot hadronic environment in the expansion phase. We employ relativistic Breit-Wigner spectral functions for the K*, (K) over bar* mesons with self-energies obtained from a self-consistent coupled-channel G-matrix approach to study the role of in-medium effects on the K* and (K) over bar* meson dynamics in heavy-ion collisions from FAIR/NICA to LHC energies. According to our analysis most of the final K* /(K) over bar*'s, that can be observed experimentally by reconstruction of the invariant mass of pi + K((K) over bar) pairs, are produced during the late hadronic phase and originate dominantly from the K((K) over bar) + pi -> K*( (K) over bar*) formation channel. The amount of K*/ (K) over bar*'s, originating from the QGP channel is comparatively small even at LHC energies and those K* /(K) over bar*'s can hardly be reconstructed experimentally due to the rescattering of final pions and (anti)kaons. This mirrors the results from our previous study on the strange vector-meson production in heavy-ion collisions at RHIC energies. We demonstrate that K* /(K) over bar* in-medium effects should be visible at FAIR/NICA and BES RHIC energies, where the production of K* /(K) over bar*'s occurs at larger net-baryon densities. Finally, we present the experimental procedures to extract the information on the resonance masses and widths by fitting the final mass spectra at LHC energies.

Abstract: We present results for the quasielastic weak production of Delta and Sigma hyperons induced by (nu) over bar. scattering off nuclei in the kinematical region of interest for accelerator neutrino experiments. We employ realistic hole spectral functions and we describe the propagation of the hyperons in the nuclear medium by means of a Monte Carlo cascade. The latter strongly modifies the kinematics and the relative production rates of the hyperons, leading to a nonvanishing Sigma(+) cross section, to a sizable enhancement of the Lambda production and to a drastic reduction of the Sigma(0) and Sigma(-) distributions. We also compute the quasielastic weak Lambda(c) production cross section, paying special attention to estimate the uncertainties induced by the model dependence of the vacuum n -> Lambda(c) weak matrix element. In this regard, the recent BESIII measurements of the branching ratios of Lambda(c) -> Lambda l(+)nu(l) (l = e, mu) are used to benchmark the available theoretical predictions.

Abstract: From lattice indications we follow a Born-Oppenheimer approximation to build a quark-antiquark static potential for J(Pc) = 1(--) charmonium states below their first S-wave meson-meson threshold. We show that a good description of the mass and decay properties of the experimentally well established psi(4260) resonance is feasible.