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Abstract: The charged-current double differential neutrino cross section, measured by the MiniBooNE Collaboration, has been analyzed using a microscopical model that accounts for, among other nuclear effects, long range nuclear (RPA) correlations and multinucleon scattering. We find that MiniBooNE data are fully compatible with the world average of the nucleon axial mass in contrast with several previous analyses which have suggested an anomalously large value. We also discuss the reliability of the algorithm used to estimate the neutrino energy. [Copyright &y& Elsevier]

We study the properties of strange and charm mesons in hot and dense matter within a self-consistent coupled-channel approach for the experimental conditions of density and temperature expected for the CBM experiment at FAIR/GSI. The in-medium solution at finite temperature accounts for Pauli blocking effects, mean-field binding of all the baryons involved, and meson self-energies. We analyse the behaviour in this hot and dense environment of dynamically-generated baryonic resonances together with the evolution with density and temperature of the strange and open-charm meson spectral functions. We test the spectral functions for strange mesons using energy-weighted sum rules and finally discuss the implications of the properties of charm mesons on the Ds0(2317) and the predicted X(3700) scalar resonances. [ABSTRACT FROM AUTHOR]

We present a microscopic model for coherent pion production off nuclei induced by neutrinos. This model is built upon a model for single nucleon processes that goes beyond the usual △ dominance by including non resonant background contributions. We include nuclear medium effects: medium corrections to △ properties and outgoing pion absorption via an optical potential. This results in major modifications to cross-sections for low energy experiments when compared with phenomenological models like Rein-Sehgal's. [ABSTRACT FROM AUTHOR]

We evaluate static properties and semileptonic decays for the ground state of doubly heavy Ξ, Ξ', Ξ * and Ω, Ω', Ω * baryons. Working in the framework of a nonrelativistic quark model, we solve the three-body problem by means of a variational ansatz made possible by heavy-quark spin symmetry constraints. To check the dependence of our results on the inter-quark interaction we use five different quark-quark potentials that include a confining term plus Coulomb and hyperfine terms coming from one-gluon exchange. Our results for static properties (masses, charge radii and magnetic moments) are, with a few exceptions for the magnetic moments, in good agreement with a previous Faddeev calculation. Our much simpler wave functions are used to evaluate semileptonic decays of doubly heavy Ξ, Ξ'( J = 1/2) and Ω, Ω'( J = 1/2) baryons. Our results for the decay widths are in good agreement with calculations done within a relativistic quark model in the quark-diquark approximation. [ABSTRACT FROM AUTHOR]

Abstract: A potential way to distinguish τ-neutrinos from antineutrinos, below the τ-production threshold, but above the pion production one, is presented. It is based on the different behavior of the neutral-current pion production off the nucleon, depending on whether it is induced by neutrinos or antineutrinos. This procedure for distinguishing τ-neutrinos from antineutrinos neither relies on any nuclear model, nor it is affected by any nuclear effect (distortion of the outgoing nucleon waves, etc.). We show that neutrino–antineutrino asymmetries occur both in the totally integrated cross sections and in the pion azimuthal differential distributions. To define the asymmetries for the latter distributions we just rely on Lorentz-invariance. All these asymmetries are independent of the lepton family and can be experimentally measured by using electron or muon neutrinos, due to the lepton family universality of the neutral-current neutrino interaction. Nevertheless and to estimate their size, we have also used the chiral model of [E. Hernández, J. Nieves, M. Valverde, hep-ph/0701149] at intermediate energies. Results are really significant since the differences between neutrino and antineutrino induced reactions are always large in all physical channels. [Copyright &y& Elsevier]

Vector meson degrees of freedom are incorporated into the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian by using a scheme which relies on spin-flavor SU(6) symmetry. The corresponding Bethe-Salpeter approximation successfully reproduces previous SU(3)-flavor WT results for the lowest-lying s-wave negative-parity baryon resonances, and it also provides some information on the dynamics of the heavier ones. Moreover, it also predicts the existence of an isoscalar spin-parity $ {\frac{3}{2}}$ - K*N bound state (strangeness +1) with a mass around 1.7-1.8GeV, unstable through K* decay. Neglecting d-wave KN decays, this state turns out to be quite narrow ( Γ≤15MeV) and it might provide clear signals in reactions like γp→¯0 pK + π - by looking at the three-body pK + π - invariant mass. [ABSTRACT FROM AUTHOR]

Working in the framework of a nonrelativistic quark model we evaluate the spectra and semileptonic decay widths for the ground state of doubly heavy Ξ and Ω baryons. We solve the three-body problem using a variational ansatz made possible by the constraints imposed by heavy-quark spin symmetry. In order to check the dependence of our results on the inter-quark interaction, we have used five different quark-quark potentials which include Coulomb and hyperfine terms coming from one-gluon exchange, plus a confining term. Our results for the spectra are in good agreement with a previous calculation done using a Faddeev approach. For the semileptonic decay our results for the total decay widths are in good agreement with the ones obtained within a relativistic quark model in the quark-diquark approximation. [ABSTRACT FROM AUTHOR]

We use standard distorted wave theory techniques and dimensional regularization to find out solutions of the nucleon–nucleon Lippman–Schwinger equation with a potential that includes one-pion exchange and additional contact terms with derivatives. Though for simplicity, we restrict the discussion to the 1S0 channel and to contact terms containing up to two derivatives, the generalization to higher waves and/or number of derivatives is straightforward. The undetermined low energy constants emerging out of the renormalization procedure are fitted to data. [Copyright &y& Elsevier]

Starting from a consistent SU(6) extension of the Weinberg-Tomozawa (WT) meson-baryon chiral Lagrangian ( Phys. Rev. D 74, 034025 (2006)), we study the s-wave meson-baryon resonances in the strangeness S = - 3 and negative-parity sectors. Those resonances are generated by solving the Bethe-Salpeter equation with the WT interaction used as kernel. The considered mesons are those of the 35- SU(6)-plet, which includes the pseudoscalar (PS) octet of pions and the vector (V) nonet of the rho-meson. For baryons we consider the 56- SU(6)-plet, made of the 1/2+ octet of the nucleon and the 3/2+ decuplet of the Delta. Quantum numbers I( J P) = 0(3/2-) are suggested for the experimental resonances Ω *(2250)- and Ω *(2380)-. Among other, resonances with I = 1 are found, which minimal quark content is sss¯ l', being s the strange quark and l, l' any of the the light up or down quarks. A clear signal for such a pentaquark would be a baryonic resonance with strangeness -3 and electric charge -2 or 0, in proton charge units. We suggest looking for K - Ξ - resonances with masses around 2100 and 2240MeV in the sector 1(1/2-), and for π ± Ω - and K - Ξ *- resonances with masses around 2260MeV in the sector 1(3/2-). [ABSTRACT FROM AUTHOR]

The semileptonic decay B→ π is studied starting from a simple quark model that takes into into account the effect of the B*-resonance. A novel, multiply subtracted, Omnès dispersion relation has been implemented to extend the predictions of the quark model to all q2 values accessible in the physical decay. By comparison to the experimental data, we extract | V ub| = (3.4±0.2(exp.)±0.7( theory))0-3. As a further test of the model, we have also studied D→ π and D→ K decays for which we get good agreement with experiment. [ABSTRACT FROM AUTHOR]

We analyze the modifications that a dense nuclear medium induces in the D s 0 ⁎ (2317) ± and D s 1 (2460) ±. In the vacuum, we consider them as isoscalar D (⁎) K and ▪ S -wave bound states, which are dynamically generated from effective interactions that lead to different Weinberg compositeness scenarios. Matter effects are incorporated through the two-meson loop functions, taking into account the self energies that the D (⁎) , ▪, K , and ▪ develop when embedded in a nuclear medium. Although particle-antiparticle [ D s 0 , s 1 (⁎) (2317 , 2460) + versus D s 0 , s 1 (⁎) (2317 , 2460) − ] lineshapes are the same in vacuum, we find extremely different density patterns in matter. This charge-conjugation asymmetry mainly stems from the very different kaon and antikaon interaction with the nucleons of the dense medium. We show that the in-medium lineshapes found for these resonances strongly depend on their D (⁎) K /▪ molecular content, and discuss how this novel feature can be used to better determine/constrain the inner structure of these exotic states. [ABSTRACT FROM AUTHOR]

New and more precise measurements of neutrino cross sections have renewed interest in a better understanding of electroweak interactions on nucleons and nuclei. This effort is crucial to achieving the precision goals of the neutrino oscillation program, making new discoveries, like the CP violation in the leptonic sector, possible. We review the recent progress in the physics of neutrino cross sections, putting emphasis on the open questions that arise in the comparison with new experimental data. Following an overview of recent neutrino experiments and future plans, we present some details about the theoretical development in the description of (anti)neutrino-induced quasielastic (QE) scattering and the role of multi-nucleon QE-like mechanisms. We cover not only pion production in nucleons and nuclei but also other inelastic channels including strangeness production and photon emission. Coherent reaction channels on nuclear targets are also discussed. Finally, we briefly describe some of the Monte Carlo event generators, which are at the core of all neutrino oscillation and cross-section measurements. [ABSTRACT FROM AUTHOR]

Based on previous studies that support the important role of the N*(2120)D13 resonance in the ?p → K+Λ(1520) reaction, we make a re-analysis of this Λ(1520) photoproduction reaction taking into account the recent CLAS differential cross-section data. In addition to the contact, t-channel K exchange, s-channel nucleon pole, and N*(2120) [previously called N*(2080)] resonance contributions, which have been considered in previous works, we also study the u-channel Λ(1115) hyperon pole term. The latter mechanism has always been ignored in all theoretical analysis, which has mostly relied on the very forward K+ angular LEPS data. It is shown that when the contributions from the N*(2120) resonance and the Λ(1115) hyperon are taken into account, both the new CLAS and the previous LEPS data can be simultaneously described. We also show that the contribution from the u-channel Λ(1115) pole term produces an enhancement for large K+ angles, and it becomes more and more relevant as the photon energy increases, being essential to describe the CLAS differential cross sections at backward angles. Furthermore, we find that the new CLAS data also favor the existence of the N*(2120) resonance and that these measurements can be used to further constrain its properties. [ABSTRACT FROM AUTHOR]

Neutral-current photon emission reactions with nucleons and nuclei are studied. These processes are important backgrounds for νμ → νe (νμ → νe) appearance oscillation experiments where electromagnetic showers instigated by electrons (positrons) and photons are not distinguishable. At intermediate energies, these reactions are dominated by the weak excitation of the Δ(1232) resonance and its subsequent decay into N?. There are also nonresonant contributions that, close to threshold, are fully determined by the effective chiral Lagrangian of strong interactions. In addition, we have also included mechanisms mediated by nucleon excitations (N*) from the second resonance region above the Δ(1232). From these states, the contribution of the D13 N*(1520) turns out to be sizable for (anti)neutrino energies above 1.5 GeV. We have extended the model to nuclear targets taking into account Pauli blocking, Fermi motion, and the in-medium Δ resonance broadening. We present our predictions for both the incoherent and coherent channels, showing the relevance of the nuclear corrections. We also discuss the target mass dependence of the cross sections. This study is important to reduce systematic effects in neutrino oscillation experiments. [ABSTRACT FROM AUTHOR]

Abstract: We use a correlated local Fermi gas (LFG) model, which accounts also for long distance corrections of the RPA type and final-state interactions, to compute the polarization of the final lepton in charged-current quasielastic neutrino scattering. The present model has been successfully used in recent studies of inclusive neutrino nucleus processes and muon capture. We investigate the relevance of nuclear effects in the particular case of τ polarization in tau-neutrino induced reactions for several kinematics of relevance for neutrino oscillation experiments. [Copyright &y& Elsevier]

We evaluate different properties of baryons with a heavy c or b quark. The use of Heavy Quark Symmetry (HQS) provides with an important simplification of the non relativistic three body problem which can be solved by means of a simple variational approach. This scheme is able to reproduce previous results obtained with more involved Faddeev calculations. The resulting wave functions are parametrized in a simple manner, and can be used to calculate further observables. [Copyright &y& Elsevier]

We have improved the tree-level model of Ref. [1] for weak production of kaons off nucleons by partially restoring unitarity. This is achieved by imposing Watson's theorem to the dominant vector and axial-vector contributions in appropriate angular momentum and isospin quantum number sectors. The observable consequences of this procedure are investigated. [ABSTRACT FROM AUTHOR]

Scaling features of the nuclear electromagnetic response functions unveil aspects of nuclear dynamics that are crucial for interpreting neutrino- and electron-scattering data. In the large momentum-transfer regime, the nucleon-density response function defines a universal scaling function, which is independent of the nature of the probe. In this work, we analyze the nucleon-density response function of 12C, neglecting collective excitations. We employ particle and hole spectral functions obtained within two distinct many-body methods, both widely used to describe electroweak reactions in nuclei. We show that the two approaches provide compatible nucleon-density scaling functions that for large momentum transfers satisfy first-kind scaling. Both methods yield scaling functions characterized by an asymmetric shape, although less pronounced than that of experimental scaling functions. This asymmetry, only mildly affected by final state interactions, is mostly due to nucleon-nucleon correlations, encoded in the continuum component of the hole spectral function. [ABSTRACT FROM AUTHOR]