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Charge-changing cross sections σ cc for mirror nuclei pair, 22 Ne and 22 Mg, on carbon and proton targets were measured at 120 MeV/nucleon. The experimental σ cc e x p. were compared with Glauber-type calculations using the known density distribution of the target and the proton distribution of the projectile. Moreover, assuming the perfect charge symmetry, the proton distribution radius of 22 Mg was deduced and compared with that from the isotope shift. We examined the possibility of the charge-changing cross section for mirror nuclei as a new method to determine the neutron skin thickness. [ABSTRACT FROM AUTHOR]

A review of recent advances in the study of the energy splitting between excited isobaric analogue states is presented. Some of the experimental developments, and new approaches, associated with spectroscopy of the most proton-rich members of isobaric multiplets, are discussed. The review focuses on the immense impact of the shell-model in the analysis of energy differences and their interpretation in terms of nuclear structure phenomena.

A review of recent advances in the study of the energy splitting between excited isobaric analogue states is presented. Some of the experimental developments, and new approaches, associated with spectroscopy of the most proton-rich members of isobaric multiplets, are discussed. The review focuses on the immense impact of the shell-model in the analysis of energy differences and their interpretation in terms of nuclear structure phenomena. [ABSTRACT FROM AUTHOR]

We report a calculation of the combined effect of photon radiation and quark mass differences on charge symmetry violation (CSV) in the parton distribution functions of the nucleon. Following a recent suggestion of Martin and Ryskin, the initial photon distribution is calculated in terms of coherent radiation from the proton as a whole, while the effect of the quark mass difference is based on a recent lattice QCD simulation. The distributions are then evolved to a scale at which they can be compared with experiment by including both QCD and QED radiation. Overall, at a scale of 5 GeV2, the total CSV effect on the phenomenologically important difference between the d and u-quark distributions is some 20% larger than the value based on quark mass differences alone. In total these sources of CSV account for approximately 40% of the NuTeV anomaly.

Nolen-Schiffer Anomaly in mirror nuclei due to the NN interactions with isospin mixing between T=0 and T=1 mesons of the same spin and parity are investigated. With the computation of coulomb energy along with the charge symmetry breaking (CSB) effects provide a reasonably accurate description of binding energy differences between 39ca- 39k- , 41cs- 41ca mirror nuclei.

Charge symmetry breaking potentials due to the exchange of pseudoscalar and vector mesons in mirror nuclei are considered. With the computation of coulmb energy along with the present charge symmetry breaking effects provide a reasonably accurate description of the binding energy differences between mirror nuclei.

Presymmetry, the hidden symmetry underlying the charge and generational patterns of quarks and leptons, is utilized for repairing the left-right asymmetry of the standard model with Dirac neutrinos. It is shown that the restoration of parity is consequent with an indispensable left-right symmetric residual presymmetry. Thus, presymmetry substantiates left-right symmetry and the experimental search for the latter is the test of the former, with the nature of neutrinos as a crucial feature that can distinguish the left-right symmetry alone and its combination with presymmetry. This phenomenological implication is in accordance with the fact that Majorana neutrinos are usually demanded in the first case, but forbidden in the second. [ABSTRACT FROM AUTHOR]

Abstract: In light of the recent discovery of the importance of the isovector EMC effect for the interpretation of the NuTeV determination of , it seems timely to reassess the central value and the errors on this fundamental Standard Model parameter derived from the NuTeV data. We also include earlier work on charge symmetry violation and the recent limits on a possible asymmetry between s and quarks. With these corrections we find a revised NuTeV result of , which is in excellent agreement with the running of predicted by the Standard Model. As a further check, we find that the separate ratios of neutral current to charge current cross-sections for neutrinos and for antineutrinos are both in agreement with the Standard Model, at just over one standard deviation, once the corrections described here are applied. [ABSTRACT FROM AUTHOR]

Abstract: M1 transitions from the state at 3.563 MeV to the ground state and to the continuum are studied in a three-body model. The bound states are described as an system in hyperspherical coordinates on a Lagrange mesh. The ground-state magnetic moment and the gamma width of the resonance are well reproduced. The halo-like structure of the resonance is confirmed and is probed by the M1 transition probability to the continuum. The spectrum is sensitive to the description of the phase shifts. The corresponding gamma width is around 1.0 meV, with optimal potentials. Charge symmetry is analyzed through a comparison with the β-delayed deuteron spectrum of 6He. In 6He, a nearly perfect cancellation effect between short-range and halo contributions was found. A similar analysis for the decay is performed; it shows that charge-symmetry breaking at large distances, due to the different binding energies and to different charges, reduces this effect. The present branching ratio should be observable with current experimental facilities. [Copyright &y& Elsevier]

Abstract: The measured energy dependence of the 7Be()8B S factor is fitted better by the cluster-model calculation of Descouvemont and Baye than by other models. It is suggested here that this may be connected with the cluster model predicting too high an absolute value of the S factor. Evidence for a breakdown of charge symmetry between the 7Li+n and 7Be+p systems is discussed and found not to be convincing. R-matrix formulae are used. [Copyright &y& Elsevier]

Abstract: Shell model calculations have been carried out using the m-scheme numerical code ANTOINE in order to elucidate the particular trend of the isoscalar matrix elements, , for isobaric triplets ranging from to . The transition energies, reduced transition probabilities and isoscalar matrix elements are predicted to a high degree of accuracy. The general agreement of between those from mirror pairs and those from nuclides support our shell model calculations. The predicted results tie together recent experimental data, and the trend of strength along the sd and beginning of the fp shells is interpreted in terms of the dynamic shell structure. Certain discrepancies arise at and isobaric triplets, which might be explained in terms of core polarization effects and the low occupancy of the orbits at the extremes of the sd shell. [Copyright &y& Elsevier]

Abstract: The Direct Investigation of a nn Association (DIANNA) is finalizing the design of a direct measurement of the nn-scattering length to be performed at the YAGUAR reactor in Snezhinsk, Russia. Extensive modeling of the neutron field, nn-scattering kinematics, and sources of detector background have verified the plan for a 3% measurement of a nn. Measurements of the neutron flux support the neutron field modeling. Initial test measurements of the neutron field inside the underground channel have confirmed calculations of the thermal neutron background. [Copyright &y& Elsevier]

One of the key experiments of the physics program of WASA-at-COSY is the determination of the p- wave contributions to the Charge Symmetry breaking amplitude in the reaction dd → 4Heπ0 at 1.2 GeV/c beam momentum. As a first step towards realisation of this goal the Charge Symmetry conserving reaction dd → 3Henπ0 was measured. For an overall theoretical analysis of CSB reactions in terms of Chiral Perturbation Theory this reaction channel will be used to gain information on the deuteron-deuteron initial state interaction for s- and p- wave pion production. [ABSTRACT FROM AUTHOR]

The measurment of the charge symmetry conserving reactions dd → 3He p π- and dd → 3He n π0 is the first step of the charge symmetry breaking physics program with WASA-at-COSY. The analysis of these channels helps to understand the experimental conditions and provides additional parameters for theoretical studies. The data have been collected in November 2007. [ABSTRACT FROM AUTHOR]