The Shockley-type surface state on Ar covered Au(1 1 1): High resolution photoemission results and the description by slab-layer DFT calculations

We present a combined experimental (angle resolved photoemission: ARUPS) and theoretical study of the Shockley-type surface state in the L-gap of the (1 1 1)-face of Au covered with one monolayer of Ar. As known also from other systems consisting of rare-gas monolayers on noble metal (1 1 1) surfaces, the adsorbed rare-gas shifts the Shockley-state towards the Fermi level and increases the spin-orbit splitting, whereas the effective band mass remains unchanged. We analyze the observed changes by a comparison with ab initio slab-layer calculations based on the density functional theory (DFT), both within the local density approximation (LDA) and the generalized gradient approximation (GGA). Although the attractive van der Waals interaction between rare-gas and substrate is not properly considered in DFT there are considerable hybridization effects which allow to describe such weakly bound adsorbates quantitatively. We show to what extent the various DFT calculations correspond to the experimental results. Furthermore, we discuss the importance of lattice relaxation and the exact absorption position into the calculations.     

A compact quantum semigroup generated by an isometry

In this paper we construct a compact quantum semigroup structure on a Toeplitz algebra. We prove the existence of a subalgebra in the dual algebra isomorphic to the algebra of regular Borel measures on a circle with the convolution product. We also prove the existence of Haar functionals in the dual algebra and in the mentioned subalgebra. We show that this compact quantum semigroup contains a dense subalgebra with the structure of a weak Hopf algebra.     

Intermolecular interactions in albumin-sulfoxide-water systems at low temperatures, investigated by means of fluorescence quenching

The effect of low temperatures on the interaction in human serum albumin (HSA)-diethyl sulfoxife (DESO)-dipropyl sulfoxide (DPSO)-water systems is investigated by means of fluorescence spectroscopy (intrinsic protein fluorescence, three-dimensional excitation/emission matrix (3D EEM)). The Stern-Volmer constants of HSA quenching are calculated for these systems. The structural changes occurring in these systems are characterized using 3D EEM profiles of HSA. It is shown that the HSA structural changes depend not only on the direct interaction of protein with sulfoxides but on structural changes in the solvent as well.     

A study of the neutrino production of <Emphasis Type="Italic">φ</Emphasis> and <Emphasis Type="Italic">D</Emphasis><Stack><Subscript><Emphasis Type="Italic">s</Emphasis></Subscript><Superscript>+</Superscript></Stack> mesons

The charged current neutrino production of φ and D _s ⁺ mesons is studied, using the data obtained with the SKAT bubble chamber exposed to the Serpukhov accelerator neutrino beam. It is found that the φ production occurs predominantly in the forward hemisphere of the hadronic c.m.s. (at x _F > 0, x _F being the Feynman variable), with the mean yield strongly exceeding the expected yield of directly produced φ mesons and varying from 〈n _φ(x _F s 0)〉 = (0.92 ± 0.34) × 10^?2 at W > 2 GeV up to (1.23 ± 0.53) × 10^?2 at W > 2.6 GeV and (1.44 ± 0.69) × 10^?2 at W > 2.9 GeV, W being the invariant mass of the hadronic system. For the first time, the inclusive yield of leading D _s ⁺ mesons carrying more than z = 0.85 of the current c-quark energy is estimated: 〈n _{D s} ⁺ (z > 0.85, W > 2.9 GeV)〉 = (6.64 ± 1.91) × 10^?2. It is shown that the shape of measured φ meson differential spectrum on xF is reproduced by that expected from the D _s ⁺ → φX decays. An indication was obtained that this expected spectrum underestimates the measured φ yield.     

Charged <Emphasis Type="Italic">ρ</Emphasis>-meson production in neutrino-induced reactions at &lt;<Emphasis Type="Italic">E</Emphasis><Subscript><Emphasis Type="Italic">ν</Emphasis></Subscript>&gt;≈ 10 GeV

The production of charged ρ mesons on nuclei and nucleons is investigated in charged current neutrino interactions at moderate energies (〈E _〉 ≈ 10 GeV), using the data obtained with SKAT bubble chamber. No strong nuclear effects are observed in ρ ⁺ and ρ ^? production. The fractions of charged and neutral pions originating from ρ decays are obtained and compared with higher-energy data. From analysis of the obtained and available data on ρ ⁺ and K*⁺(892) neutrino production, the strangeness suppression factor is extracted: λ _s = 0.18 ± 0.03. Estimation is obtained for cross section of coherent ρ ⁺ neutrino production on nuclei.     

Deposition of high-ohmic oriented ZnO films on glass,Si, and PEDOT-PSS,PEDOT-PSS(PVA) substrates at low temperatures by DC-magnetron sputtering

Using the technique of DC-magnetron sputtering of zinc target in the temperature range from −30°C to 30°C, we have obtained high-ohmic ZnO films (1.1×10⁹, 2×10¹¹, 1.3×10⁶, and 10⁸ Ω cm) on the substrates of glass, Si, and composites based on poly(3, 4-etylendioxythiophene) doped with polystyrensulfonic acid (PEDOT-PSS), and flexible composites of PEDOT-PSS in polymer matrix of polyvinyl alcohol (PVA). Structural, optical, and electrophysical characteristics of ZnO films prepared on different substrates were studied. Films obtained in certain technological regime are on all substrates oriented along crystallographic direction (002) and have transmission coefficient of the order 80–90% in the range 400–1000 nm. The developed technology for fabrication of high-ohmic grain-oriented ZnO films at low substrate temperatures can be applied to creation of functional elements in acousto- and bioelectronics.     

X-ray diffraction in KDP crystal in the presence of temperature gradient

We investigate the effect of temperature gradient on the intensity of X-ray radiation reflected from different atomic planes of a KDP crystal, depending on the crystal thickness. We have studied the phenomenon of transfer of the X-ray beam intensity for x- and z-cuts of the KDP crystal in the presence and in the absence of temperature gradient. It is shown that the intensities of reflected radiations do not saturate because in conditions of the experiment the further increase in temperature gradient leads to destruction of the sample. It is revealed that in some cases at small values of temperature gradient the intensity of reflected radiation decreases initially by more than 10%, then increases monotonically with the increase in temperature gradient.     

Measurement of(di)muons from heavy flavour decay in p-p collisions at 14 TeV with ALICE at the LHC

We present the performance of the ALICE muon spectrometer for measuring the charm and beauty inclusive pt differential production cross sections via single muons and unlike-sign dimuons in proton-proton collisions at(√s) = 14 TeV.     

X‐ray focusing by the system of refractive lens(es) placed inside asymmetric channel‐cut crystals

An X‐ray one‐dimensionally focusing system, a refracting–diffracting lens (RDL), composed of Bragg double‐asymmetric‐reflecting two‐crystal plane parallel plates and a double‐concave cylindrical parabolic lens placed in the gap between the plates is described. It is shown that the focal length of the RDL is equal to the focal distance of the separate lens multiplied by the square of the asymmetry factor. One can obtain RDLs with different focal lengths for certain applications. Using the point‐source function of dynamic diffraction, as well as the Green function in a vacuum with parabolic approximation, an expression for the double‐diffracted beam amplitude for an arbitrary incident wave is presented. Focusing of the plane incident wave and imaging of a point source are studied. The cases of non‐absorptive and absorptive lenses are discussed. The intensity distribution in the focusing plane and on the focusing line, and its dependence on wavelength, deviation from the Bragg angle and magnification is studied. Geometrical optical considerations are also given. RDLs can be applied to focus radiation from both laboratory and synchrotron X‐ray sources, for X‐ray imaging of objects, and for obtaining high‐intensity beams. RDLs can also be applied in X‐ray astronomy.     

Structural imperfections of crystals as a result of ion implantation

The diffraction of X-rays has been studied in two-crystal interferometers, the crystals of which had equal interplanar distances and between the blocks of which a non-diffracting zone was formed as a result of ion implantation. Also the X-ray diffraction was studied in two-crystal interferometers, the interplanar distances of which were different and the non-diffracting zone between the crystals had zero width. It was shown in plane wave approximation that the Moiré patterns should not be formed in case of former interferometers and necessarily arose with the latter type interferometers.