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Abstract: The final state interactions (FSI) model in which soft rescattering of low mass intermediate states dominates is suggested. It explains why the strong interaction phases are large in the channel and are considerably smaller in the one. Direct CP asymmetries of decays which are determined by FSI phases are considered as well. [Copyright &y& Elsevier]

Abstract: We consider the bosonic sector of the maximally supersymmetric SYM model and show that anomalous dimension of the twist-3 single-trace composite operators built of scalar fields, recently calculated up to the four-loop order, can be generated by a compact reciprocity respecting evolution kernel. [Copyright &y& Elsevier]

Abstract: We study the neutral minima of two-Higgs doublet models, showing that these potentials can have at least two such minima with different depths. We analyse the phenomenology of these minima for the several types of two-Higgs doublet potentials, where CP is explicitly broken, spontaneously broken or preserved. We discover that it is possible to have a neutral minimum in these potentials where the masses of the known particles have their standard values, with another deeper minimum where those same particles acquire different masses. [Copyright &y& Elsevier]

Abstract: Quadrupole deformation parameters, , have been deduced for 36,38,40Si from measured inelastic proton-scattering cross sections. Due to the strong subshell gap, low-lying quadrupole collectivity in these nuclei is attributed to the excitation of valence neutrons. Enhanced collectivity at indicates a reduced shell gap at large neutron excess in this chain of isotopes. Data are compared to large-scale shell-model calculations and prior Coulomb excitation measurements on 36,38Si. [Copyright &y& Elsevier]

Abstract: We study some physical consequences of the introduction of a Lorentz-violating modification term in the linearized gravity, which leads to modified dispersion relations for gravitational waves in the vacuum. We discuss two possible mechanisms for the induction of such a term in the Lagrangian. First, it is generated at the quantum level by a Lorentz-breaking coupling of the gravity field to a spinor field. Second, it appears as consequence of a particular modification of the Poisson algebra of the canonical variables, in the spirit of the so-called “noncommutative fields approach”. [Copyright &y& Elsevier]

Abstract: Károlyházy uncertainty relation, which can be viewed also as a relation between UV and IR scales in the framework of an effective quantum field theory satisfying a black hole entropy bound, strongly favors the existence of dark energy with its observed value. Here we estimate the dynamics of dark energy predicted by the Károlyházy relation during the cosmological evolution of the universe. [Copyright &y& Elsevier]

Abstract: We construct a DGP inspired braneworld scenario where a scalar field non-minimally coupled to the induced Ricci curvature is present on the brane. We show that this model allows for an embedding of the standard Friedmann cosmology in the sense that the cosmological evolution of the background metric on the brane can be described by the standard Friedmann equation. [Copyright &y& Elsevier]

Abstract: The reaction is a very good isospin 3/2 filter for studying decaying to . With an effective Lagrangian approach, contributions from a previous ignored sub--threshold resonance are fully included in addition to those already considered in previous calculations. It is found that the resonance gives an overwhelmingly dominant contribution for energies very close to threshold, with a very important contribution from the t-channel ρ exchange. This solves the problem that all previous calculations seriously underestimate the near-threshold cross section by order(s) of magnitude. Many important implications of the results are discussed. [Copyright &y& Elsevier]

Abstract: One-parameter exactly separable versions of the X(5) and X(5)- models, labelled as ES-X(5) and ES-X(5)- respectively, are derived by using in the Bohr Hamiltonian potentials of the form . Unlike X(5), in these models the and bands are treated on equal footing. Spacings within the band are well reproduced by both models, while spacings within the band are well reproduced only by ES-X(5)-, for which several nuclei with ratios and [normalized to ] and bandheads corresponding to the model predictions have been found. [Copyright &y& Elsevier]

Abstract: In frame of a phenomenological approach based on Compton-like Feynman amplitudes, we study multi-pion production in antiproton nucleon collisions. The main interest of this reaction is related to the possibility to study the properties of the presumable atom and of its resonances. For the case of formation of a scalar or pseudoscalar resonant state, with numerical results are obtained. The differential cross section in an experimental set-up where the pions invariant mass is measured, is given with explicit dependence on the lepton pair and pions invariant mass. [Copyright &y& Elsevier]

Abstract: Conventional nucleon–nucleon potentials with strong short-range repulsion require contributions from high-momentum wave function components even for low-energy observables such as the deuteron binding energy. This can lead to the misconception that reproducing high-energy phase shifts is important for such observables. Interactions derived via the similarity renormalization group decouple high-energy and low-energy physics while preserving the phase shifts from the starting potential. They are used to show that high-momentum components (and high-energy phase shifts) can be set to zero when using low-momentum interactions, without losing information relevant for low-energy observables. [Copyright &y& Elsevier]

Abstract: We consider the fermionic contributions to the free energy of noncommutative QED at finite temperature T. This analysis extends the main results of our previous investigation where we have considered the pure bosonic sector of the theory. For large values of (θ is the magnitude of the noncommutative parameters) the fermionic contributions decrease the value of the critical temperature, above which there occurs a thermodynamic instability. [Copyright &y& Elsevier]

Abstract: We present holographic arguments to predict properties of strongly coupled gravitational systems in terms of weakly coupled gauge theories. In particular we relate the latest computed value for the Choptuik critical exponent in black hole formation in five dimensions, , to the saturation exponent of four-dimensional Yang–Mills theory in the Regge limit, . [Copyright &y& Elsevier]

Abstract: We have studied the scalar field as well as the fermionic field perturbations in the background of the massless BTZ black holes. Comparing with the perturbation results in the generic non-rotating BTZ black hole background, we found that the massless BTZ hole contains only normal modes in the perturbations. We argued that this special property reflects that the massless BTZ black hole is a different phase from that of the generic non-rotating BTZ hole. [Copyright &y& Elsevier]

Abstract: The distribution of the decays in the Dalitz plot has been measured by the NA48/2 experiment at the CERN SPS with a sample of fully reconstructed events. With the standard Particle Data Group parameterization the following values of the slope parameters were obtained: , , . The quality and statistical accuracy of the data have allowed an improvement in precision by more than an order of magnitude, and are such as to warrant a more elaborate theoretical treatment, including pion–pion rescattering, which is in preparation. [Copyright &y& Elsevier]

Abstract: The soft breaking of gauge or other symmetries is the typical Quantum Field Theory phenomenon. In many cases one can apply the Stückelberg procedure, which means introducing some additional field or fields and restore the gauge symmetry. The original softly broken theory corresponds to a particular choice of the gauge fixing condition. In this Letter we use this scheme for performing quantum calculations for some softly broken gauge theories in an arbitrary curved space–time. The following examples are treated in details: Proca field, massive QED and massive torsion coupled to fermion. Furthermore we present a qualitative discussion of the discontinuity of quantum effects in the massive spin-2 field theory, paying special attention to the similarity and differences with the massless limit in the spin-1 case. [Copyright &y& Elsevier]

Abstract: We present arguments for the existence of charged, rotating black holes with equal-magnitude angular momenta in an odd number of dimensions . These solutions possess a regular horizon of spherical topology and approach asymptotically the anti-de Sitter spacetime background. We analyze their global charges, their gyromagnetic ratio and their horizon properties. [Copyright &y& Elsevier]

Abstract: We investigate perturbative aspects of gravity with a general Lagrangian, as well as nonperturbative dilatonic solutions. For the first part, we are interested in stability and the definition of asymptotic charges. The main result of this study is that, while generic theories are stable under metric perturbations, they are expected to show instabilities against curvature perturbations when the Lagrangian includes terms. For the second part, one is interested on exact solutions, and we explicitly construct kink-like solutions of the Liouville type for the dilaton field for having the form , in two and in four dimensions. [Copyright &y& Elsevier]

Abstract: We discuss FRW universe with time-dependent EoS dark fluid which leads to multiple de Sitter space. This model (as well as its scalar-tensor version) may be considered as some classical analog of cosmological landscape. The universe expansion history may look as transitions between different de Sitter eras what suggests the interesting solution for cosmological constant problem. For specific time-dependent EoS dark fluid the possibility of transitions between universe regions with positive and negative cosmological constant is also established. [Copyright &y& Elsevier]

Abstract: We consider constraints on long-lived charged scalar leptons in supersymmetric models, where gravitino is the lightest superparticle. We study the decay and hadronization processes of . We also take into account the significant enhancement of 6L production due to the formation of the bound-state ; for this purpose, we use the reaction rate given by the most recent calculation based on coupled-channel method. [Copyright &y& Elsevier]

Abstract: A low-energy non-unitary leptonic mixing matrix is a generic effect of a large class of theories accounting for neutrino masses. It is shown how the extra CP-odd phases of a general non-unitary matrix allow for sizeable CP-asymmetries in channels other than those dominant in the standard unitary case. The channel turns out to be an excellent tool to further constrain moduli and phases. Furthermore, we clarify the relationship between our approach and the so-called “non-standard neutrino interactions” schemes: the sensitivities explored here apply as well to such constructions. [Copyright &y& Elsevier]

Abstract: We present analytical results for all six-photon helicity amplitudes. For the computation of this loop induced process two recently developed methods, based on form factor decomposition and on multiple cuts, have been used. We obtain compact results, demonstrating the applicability of both methods to one-loop amplitudes relevant to precision collider phenomenology. [Copyright &y& Elsevier]

Abstract: Correlations between p and at transverse momenta typical of enhanced baryon production in Au+Au collisions are reported. The PHENIX experiment has measured same and opposite sign baryon pairs in Au+Au collisions at . Correlated production of p and with the trigger particle from the range and the associated particle with is observed to be nearly independent of the centrality of the collisions. Same sign pairs show no correlation at any centrality. The conditional yield of mesons triggered by baryons (and anti-baryons) and mesons in the same range rises with increasing centrality, except for the most central collisions, where baryons show a significantly smaller number of associated mesons. These data are consistent with a picture in which hard scattered partons produce correlated p and in the region of the baryon excess. [Copyright &y& Elsevier]

Abstract: In this work we show that the existence of a complete biorthonormal set of eigenvectors of the effective Hamiltonian governing the time evolution of neutral meson system is a necessary condition for diagonalizability of such a Hamiltonian. We also study the possibility of probing the CPT invariance by observing the time dependence of cascade decays of type by employing such basis and exactly determine the CPT violation parameter by comparing the time dependence of the cascade decays of tagged and tagged . [Copyright &y& Elsevier]

Abstract: The quality of the narrow-width approximation is examined for partonic and convolved cross sections of sample processes. By comparison with accurate predictions significant limitations are revealed. [Copyright &y& Elsevier]

Abstract: I propose a scaling analysis of the hadron multiplicity ratio measured in Deep Inelastic Scattering on nuclear targets as a tool to distinguish energy loss and nuclear absorption effects on hadron suppression in cold nuclear matter. The proposed scaling variable is a function of the hadron fractional energy and of the virtual photon energy. Its functional form, which depends on a parameter λ, can be fixed by general theoretical considerations and encompasses both energy loss and absorption models. The parameter λ is fitted to HERMES experimental data and shown to favor prehadron nuclear absorption as leading mechanism for hadron suppression as opposed to quark energy loss. [Copyright &y& Elsevier]

Abstract: The transition from asymmetric to symmetric fission as dependent on the excitation energy and nucleon composition of fissioning Th and Pa nuclei is investigated for the 232Th(n, F) and 232Th(p, F) reactions, respectively. Observed neutron-induced fission cross sections are described in a fission/evaporation approximation. A separate relatively high outer fission barrier with significant curvature was assumed for the symmetric mode, while the inner one () was assumed to be the same for symmetric and asymmetric modes. Axial asymmetry and mass symmetry is assumed for the outer saddle of the SL-mode, as distinct from the AS-mode. A drop of to ∼1–1.5 MeV for Th and Pa nuclei with is responsible for the increase of the symmetric fission contribution to 225,229,230,231,232Th(n, F) or 232Th(p, F) fission cross sections with nucleon energy up to . It is shown that with increase of the above the 229,230,231,232Th(n, F) fission cross sections are no longer dependent on the Th target nuclide fissility. The dependence of 232Th fission cross section on the incident particle (n or p) is predicted to be different than in case of 238U target nuclide. [Copyright &y& Elsevier]

Abstract: We present the results of a complete two-loop calculation at order of the nucleon mass in manifestly Lorentz-invariant chiral perturbation theory. The renormalization is performed using the reformulated infrared renormalization, which allows for the treatment of two-loop integrals while preserving all relevant symmetries, in particular chiral symmetry. [Copyright &y& Elsevier]

Abstract: A measurement of the neutrino asymmetry is presented which represents the first search for new physics using polarized radioactive atoms initially cooled and confined in a magneto-optical trap. Optical pumping and photoionization techniques are used to generate and measure, in situ, a highly spin-polarized sample of the short-lived -emitter 37K. The angular distribution of neutrinos from this polarized decay, inferred from the daughter recoil asymmetry, is used to search for a hypothetical current in the weak interaction. We find the ν asymmetry parameter to be , in agreement with the standard model''s purely interaction. [Copyright &y& Elsevier]