Parity-violating nucleon-nucleon interaction from different approaches

Two-pion exchange parity-violating nucleon-nucleon interactions from recent effective field theories and earlier fully covariant approaches are investigated. The potentials are compared with the idea to obtain better insight on the role of low-energy constants appearing in the effective field theory approach and the convergence of this one in terms of a perturbative series. The results are illustrated by considering the longitudinal asymmetry of polarized protons scattering off protons, $\vec{p}+p -> p+p$, and the asymmetry of the photon emission in radiative capture of polarized neutrons by protons, $\vec{n}+p -> d+\gamma$.Comment: 31 page

The Structure and Mechanical Properties of Bridge Steel Weldings With Glass-Steel Liners

A new technology is developed for welding multi-span bridge constructions. The mechanical properties and structure of the low-carbon bridge steel welds have been studied. The welding parameters and application of steel-glass liners provide for long-term service of steel constructions in conformity with the welding industry specifications

Radio-frequency Bloch-transistor electrometer

A quantum-limited electrometer based on charge modulation of the Josephson supercurrent in the Bloch transistor inserted into a superconducting ring is proposed. As this ring is inductive coupled to a high-Q resonance tank circuit, the variations of the charge on the transistor island (input signal) are converted into variations of amplitude and phase of radio-frequency oscillations in the tank. These variations are amplified and then detected. The output noise, the back-action fluctuations and their cross-correlation are computed. It is shown that our device enables measurements of the charge with a sensitivity which is determined by the energy resolution of its amplifier, that can be reduced down to the standard quantum limit of \hbar/2. On the basis of this setup a "back-action-evading" scheme of the charge measurements is proposed.Comment: 5 pages incl. 2 figure

Parity nonconservation effects in the photodesintegration of polarized deuterons

P-odd correlations in the deuteron photodesintegration are considered. The $\pi$-meson exchange is not operative in the case of unpolarized deuterons. For polarized deuterons a P-odd correlation due to the $\pi$-meson exchange is about $3 \times 10^{-9}$. Short-distance P-odd contributions exceed essentially than the contribution of the $\pi$-meson exchange.Comment: 12 pages, Latex, 3 figure

Opto-Electronic Characterization of Three Dimensional Topological Insulators

We demonstrate that the terahertz/infrared radiation induced photogalvanic effect, which is sensitive to the surface symmetry and scattering details, can be applied to study the high frequency conductivity of the surface states in (Bi1-xSbx)2Te3 based three dimensional (3D) topological insulators (TI). In particular, measuring the polarization dependence of the photogalvanic current and scanning with a micrometre sized beam spot across the sample, provides access to (i) topographical inhomogeneity's in the electronic properties of the surface states and (ii) the local domain orientation. An important advantage of the proposed method is that it can be applied to study TIs at room temperature and even in materials with a high electron density of bulk carriers.Comment: 6 pages, 4 figure

Parity Violation in gamma proton Compton Scattering

A measurement of parity-violating spin-dependent gamma proton Compton scattering will provide a theoretically clean determination of the parity-violating pion-nucleon coupling constant $h_{\pi NN}^{(1)}$. We calculate the leading parity-violating amplitude arising from one-loop pion graphs in chiral perturbation theory. An asymmetry of ~5 10^{-8} is estimated for Compton scattering of 100 MeV photons.Comment: 6 pages, 1 figure, latex. Reference adde

Study of Scintillator Strip with Wavelength Shifting Fiber and Silicon Photomultiplier

The performance of the $200\times2.5\times1$ cm$^3$ plastic scintillator strip with wavelength shifting fiber read-out by two novel photodetectors called Silicon PhotoMultipliers (SiPMs) is discussed. The advantages of SiPM relative to the traditional multichannel photomultiplier are shown. Light yield and light attenuation measurements are presented. This technique can be used in muon or calorimeter systems.Comment: 9 pages, 5 figure

NEW DATA ON AGE AND NATURE OF CARBONIZATION WITHIN SOUTHERN FLANK OF THE BAIKAL LEDGE OF THE SIBERIAN CRATON BASEMENT

The Baikal ledge rock formations in the Siberian craton structure are included in the Akitkan mobile belt which is considered as the Late Paleoproterozoic independent island arc system moved up to the ancient basement during the terrains amalgamation 1.91–2.00 Ga ago (Fig. 1) [Rosen, 2003; Gladkochub et al., 2009; Didenko et al., 2013].The Baikal ledge rock formations in the Siberian craton structure are included in the Akitkan mobile belt which is considered as the Late Paleoproterozoic independent island arc system moved up to the ancient basement during the terrains amalgamation 1.91–2.00 Ga ago (Fig. 1) [Rosen, 2003; Gladkochub et al., 2009; Didenko et al., 2013]

Three-body problem for ultracold atoms in quasi-one-dimensional traps

We study the three-body problem for both fermionic and bosonic cold atom gases in a parabolic transverse trap of lengthscale $a_\perp$. For this quasi-one-dimensional (1D) problem, there is a two-body bound state (dimer) for any sign of the 3D scattering length $a$, and a confinement-induced scattering resonance. The fermionic three-body problem is universal and characterized by two atom-dimer scattering lengths, $a_{ad}$ and $b_{ad}$. In the tightly bound `dimer limit', $a_\perp/a\to\infty$, we find $b_{ad}=0$, and $a_{ad}$ is linked to the 3D atom-dimer scattering length. In the weakly bound `BCS limit', $a_\perp/a\to-\infty$, a connection to the Bethe Ansatz is established, which allows for exact results. The full crossover is obtained numerically. The bosonic three-body problem, however, is non-universal: $a_{ad}$ and $b_{ad}$ depend both on $a_\perp/a$ and on a parameter $R^*$ related to the sharpness of the resonance. Scattering solutions are qualitatively similar to fermionic ones. We predict the existence of a single confinement-induced three-body bound state (trimer) for bosons.Comment: 20 pages, 6 figures, accepted for publication in PRA, appendix on the derivation of an integral formula for the Hurvitz zeta functio