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In this contribution we discuss the properties of nucleons and atomic nuclei in the framework of in-medium modified chiral soliton model. The mesonic Lagrangian of the model takes into account an influence of surrounding nuclear environment to the nucleon properties. The model correctly describes the Equations of State of isospin-symmetric and isospin-asymmetric nuclear matter near the nuclear saturation density ρ0. An extrapolation of the results to high density region allows to describe the properties of neutron stars. The model also can be applied to analysis of the properties of mirror nuclei. [ABSTRACT FROM AUTHOR]

We discuss properties of the interaction of slow neutrons with nano-dispersed media and their application for neutron reflectors. In order to increase the accuracy of model simulation of the interaction of neutrons with nanopowders, we perform precise quantum mechanical calculation of potential scattering of neutrons on single nanoparticles using the method of phase functions. We compare results of precise calculations with those performed within first Born approximation for nanodiamonds with the radius of 2-5 nm and for neutron energies 3 × 10-10 eV. Born approximation overestimates the probability of scattering to large angles, while the accuracy of evaluation of integral characteristics (cross sections, albedo) is acceptable. Using Monte-Carlo method, we calculate albedo of neutrons from different layers of piled up diamond nanopowder. [ABSTRACT FROM AUTHOR]

In the framework of the two-group configuration model we obtain formulas for the reduced transition rates for beta and gamma transitions in even-even, odd-odd, even-odd, and odd-even nuclei. We explored dependencies of the transition rates on the occupancies of the involved subshells, as well as on the spin values of the initial and final states. The obtained formulas are useful for the qualitative spectroscopic analysis of experimental data, particulary in the regions of magicity, including the regions of the 'remote' nuclei. [ABSTRACT FROM AUTHOR]

The spectra of low-lying states of the Be and B mirror nuclei in the excitation-energy range between 0 and 5 MeV are considered within the microscopic α + α + n( p) three-cluster model, which is a three-cluster variant of the algebraic version of the resonating-group method. Attention is given primarily to studying the nature of resonance states in a three-cluster continuum. A detailed comparison of the results obtained in this way with experimental data and with results of other microscopic calculations is performed. [ABSTRACT FROM AUTHOR]

A relation between quantities that characterize the breaking of the charge symmetry of nuclear forces in systems of two and three nucleons is found on the basis of an analysis of the binding-energy difference between the H and He mirror nuclei. For the neutron-neutron scattering length and effective range, the values of a = −18.38(55) fm and r = 2.84(4) fm, respectively, were obtained by using purely nuclear parameters of proton-proton scattering in the S state. The calculated values agree with present-day experimental results. [ABSTRACT FROM AUTHOR]

Results of a comparative analysis of processes leading to the production of mirror nuclei Li and Be in O p collisions at a momentum of 3.25 GeV/ c per nucleon are presented. A comparison of associated multiplicities of accompanying particles is performed. The first results on the mean multiplicity of neutrons appearing as fragments are described. [ABSTRACT FROM AUTHOR]

Experimental mirror energy differences (MED) for nuclei lying in the middle and the second part of the 1 f7/2 shell are compared with shell model calculations in the 1 f7/2 and in the full pf configuration spaces, as well as with cranked shell model calculations. MED plots are fully consistent with the description which emerges from the interpretation of SM calculations: i.e. the band-crossing of the gs band with high- K bands in A = 51 and 50 mirror pairs, as well as the seniority-3 quasi band-termination at $\ensuremath I^{\pi} = 19/2^-$ in A = 49 . Rotational alignment effects are excluded, contrarily to what even recently proposed. Some inconsistencies, as well as definition improprieties, are pointed out in the topical literature. [ABSTRACT FROM AUTHOR]

Atmospheric, solar, reactor and accelerator neutrino oscillation experiments have measured Δm212, sin2 θ12, ∣Δm2 23∣ and sin2 2θ23. The next stage of the oscillation studies should be the observation of a finite sin2 2θ13. If a non-zero sin2 2θ13 is observed, the subsequent goals should be the observation of the CP violation and the determination sign of Δm2 23. Possible future neutrino oscillation experiments that could assess these questions are discussed. [ABSTRACT FROM AUTHOR]

The role of the band quantum number K in influencing the character of allowed $ \beta$ transitions in heavy deformed nuclei is examined. The conditions for the occurrence of K -forbidden decays in this region are explored. Specific cases of “allowed” $ \beta$ decays proceeding via $ \Delta$ K = 2 to $ \Delta$ K = 6 channels are presented to illustrate the phenomenon. The listed $ \Delta$ K = 2 transitions, which by themselves contribute over 10% of all the presently known allowed transitions for A $ \geq$ 228 nuclei, are seen to have an average $\ensuremath\log ft \geq 9.0$ , which is clearly outside the normal range for allowed transitions. It is concluded that, wherever the $ \beta$ -connected states can be confidently labelled using the $\ensuremath I^{\pi}K$ quantum numbers, the K -forbiddenness is in general as significant as that involving the other two (spin and parity) quantum numbers. [ABSTRACT FROM AUTHOR]

A comparative analysis of the inclusive production of 3H and 3He nuclei in 16O p interactions at a momentum of 3.25 GeV/ c per nucleon is performed, and it is shown that the formation of these mirror nuclei occurs under close physical conditions, the distinction between their binding energies having no significant effect on the formation of the nuclei. [ABSTRACT FROM AUTHOR]

The operation of detectors irradiated with 8-MeV protons at a fluence of 3 × 1014 cm−2 has been studied. The detectors were based on modern CVD-grown n-4 H-SiC films with a concentration of uncompensated donors equal to ∼2 × 1014 cm−3 and a thickness of 55 μm. The high concentration of primary radiation defects (∼2 × 1017 cm−3) determined the deep compensation of the films. The basic characteristics of the detectors—pulse amplitude and resolution—exhibited temporal instability. This effect is due to prolonged capture of nonequilibrium carriers by radiation centers and the resulting appearance of a polarization voltage in the bulk of the detector. The kinetics of attainment of steady values by the quantities specified above was analyzed. [ABSTRACT FROM AUTHOR]

By using the quark-exchange formalism, the realistic Faddeev wave function and the Fermi motion effect, we investigate the deep inelastic electron scattering from A = 3 mirror nuclei in the deep-valence region. The initial valence quark input is taken from the GRV's (Glück, Reya and Vogt) fitting procedure and the next-to-leading-order QCD evolution on F 2 p( x, Q 2) which gives a very good fit to the available data in the ( x, Q 2)-plane. It is shown that the free neutron to proton structure functions ratio can be extracted from the corresponding EMC ratios for 3He and 3H mirror nuclei by using the self-consistent iteration procedure and the results are in good agreement with the other theoretical models as well as the present available experimental data and especially the projected data expected from the proposed 11GeV Jefferson Laboratory in the near future. [ABSTRACT FROM AUTHOR]

It has been realised recently that charge symmetry of the nucleon-nucleon interaction leads to a certain relation between Asymptotic Normalization Coefficients (ANCs) in mirror-conjugated one-nucleon overlap integrals. This relation can be approximated by a simple analytical formula that involves mirror neutron and proton separation energies, the core charge and the range of the strong nucleon-core interaction. We perform detailed microscopic multi-channel cluster model calculations and compare their predictions to the simple analytical formula as well as to calculations within a single-particle model in which mirror symmetry in potential wells and spectroscopic factors are assumed. The validity of the latter assumptions is verified on the basis of microscopic cluster model calculations. For mirror pairs in which one of the states is above the proton decay threshold, a link exists between the proton partial width and the ANC of the mirror neutron. This link is given by an approximate analytical formula similar to that for a bound-bound mirror pair. We compare predictions of this formula to the results of microscopic cluster model calculations. Mirror symmetry in ANCs can be used to predict cross sections for proton capture at stellar energies using neutron ANCs measured with stable or “less radioactive” beams. [ABSTRACT FROM AUTHOR]

Binding energies of the A = 48 isobars and their charge radii are defined on the basis of self-consistent calculations and using the concept of isobaric symmetry in nuclei. [ABSTRACT FROM AUTHOR]

The properties of three pairs of mirror nuclei13N-13C,15N-15O and21Na-21Ne (these mirror nuclei are all made of a good inert core plus an unpaired valence nucleon) are investigated by using the nonlinear relativistic mean-field (RMF) theory. It is found that the calculated binding energies with two different parameter sets are very close to the experimental ones for both the ground states and the excited states except for the large deformed nuclei. The calculations show that the 2s1/2 excited states of15N and of21Na are both weakly bound with a proton halo and a proton skin (or a pigmy proton skin), respectively. In addition, the 1d5/2 excited state of13C and the 2s1/2 excited state of15O are also weakly bound with a neutron skin, respectively. The ratio of the valence nucleon radius to matter radius is deduced and it can be regarded as an additional criterion for the existence of exotic structure. The unbound 2s1/2 and 1d5/2 excited states of13N are also discussed. [ABSTRACT FROM AUTHOR]

The effects of the entrance channel and shell structure on the experimental evaporation residues have been studied by analyzing the 32S + 182W, 48Ti + 166Er and 60Ni + 154Sm reactions leading to 214Th*. the 40Ar + 181Ta reaction leading to 221Pa*; the 48 + 243Am, 248Cm, 249 reactions leading to the 291115, 296116 and 297118 superheavy compound nuclei, respectively. The fusion mechanism and the formation of evaporation residues of heavy and superheavy nuclei have been studied. In calculations of the excitation functions for capture, fusion and evaporation residues we used such characteristics as mass asymmetry of nuclei in the entrance channel, binding energies and shape of colliding nuclei, potential energy surface, driving potential, partial-fusion cross-sections and survival probability of the compound nucleus, Γn/ Γf ratio at each step along the de-excitation cascade of the compound nucleus. The calculations have allowed us to make useful conclusions about the mechanism of the fusion-fission process, which is in competition with the quasifission process, and the production of the evaporation residues. [ABSTRACT FROM AUTHOR]

The mirror nuclei 25Mg and 25A1 are expected to have very similar structures. The Gamow-Teller (GT) transitions from the J&b.pi; = 5/2+ ground state of 25Mg to the excited states in 25A1 were studied by high-resolution measurements of the 25Mg(3He, t) charge-exchange reaction at 0° and at 140 MeV/nucleon. Assuming the usual J&b.pi; = 1+ selection rule for the spin-isospin-type GT transitions, the states with J&b.pi; = 3/2+, 5/2+, and 7/2+ should be excited. However, of the more than ten states with these J&b.pi; values below 6 MeV excitation energy, only the 5/2+ ground state and the 7/2+, 1.613 MeV state in 25A1 were strongly populated, while all other states were strongly suppressed. The analysis of Mi transitions in 25Mg also suggested a very similar feature for the analogous Mi transitions. Both 25Mg and 25A1 are known to be largely deformed, and most low-lying states can be interpreted in terms of one-particle quantum numbers in the deformed potential and the associated rotational spectra. The observed suppression can be explained in terms of the K quantum number selection rules that are inherent to axially deformed nuclei. [ABSTRACT FROM AUTHOR]

The mirror odd nuclei [sup 7]Li and [sup 7]Be and the neutron-rich nucleus [sup 6]He are considered within a microscopic approach relying on the variational principle. The binding energies of the nuclei, their root-mean-square radii, and the electron charge C0 and C2 form factors are calculated. The resulting form factors are compared with the predictions of the independent-particle model that assumes intermediate coupling. The sensitivity of the nuclear properties obtained here to the choice of nucleon-nucleon potential, to deviations of the nuclear deformation from that which follows from a variation of the total-energy functionals, and to taking projections onto states characterized by definite values of the total angular momentum and its projection is analyzed. A comparison with experimental data is performed. [ABSTRACT FROM AUTHOR]

Presents information on the interdiffusion in Co/C soft X-ray multilayer mirrors, with reference to a study conducted on the issue. Methodology used to conduct the study; Results of the study.

Eighty years of microscopy have established a conventional view of nuclear organization: dark-staining heterochromatin at the nuclear periphery and light-staining euchromatin in the interior. This nuclear architecture is inverted in rod cells of nocturnal mammals, demonstrating a unique functional nuclear genome reorganization specifically adapted for light transmission. [ABSTRACT FROM AUTHOR]

Analyzes the stability of a nuclei. Elements of a nuclei; Details on the nuclear transformation; Role of X-ray spectroscopy in nuclear transformation; Stabilization of large atomic nucleus by its excess of neutrons.