Measurement of the yields of positively charged particles at an angle of 35° in proton interactions with nuclear targets at an energy of 50 GeV

Momentum spectra of cumulative particles in the region of high transverse momenta (P _T ) in pA → h ⁺ + X reactions were obtained for the first time. The experiment in which this was done was performed at the SPIN setup (Institute for High Energy Physics, Protvino) in a beam of 50-GeV protons interacting with C, Al, Cu, and W nuclei. Positively charged particles were detected at a laboratory angle of 35° and in the transverse-momentum range between 0.6 and 3.7 GeV/c. A strong dependence of the particle-production cross section on the atomic number was observed. A comparison with the results of calculations based on the HIJING and UrQMD models was performed in the subcumulative region.     

Production of ϒ meon in pp colliion at $$\qrt $$ = 7 and 8 TeV in the LHCb experiment

The LHCb results on the production of ? mesons in pp collisions at \(\sqrt s\) = 7 and 8 TeV are briefly reviewed.     

Production of High-Transverse-Momentum Deuterons and Tritons at an Angle of 40 $${{}^{\circ}}$$ in Proton–Nucleus Interactions at a Beam Energy of 50 GeV

Physics of Atomic Nuclei - Data on the production of positively charged particles emitted at an angle of 40 $${}^{\circ}$$ (in the laboratory frame) with transverse momenta of up to 2.7 GeV $$/c$$...     

A method of measuring the refractive index of extraordinary ray in uniaxial crystal with optic axis at an arbitrary orientation

A new equation to measure the refractive index of extraordinary ray in uniaxial crystal with the optic axis at an arbitrary orientation has been given in this letter,and the term in this equation makes the measurements to be relatively easy.The theoretical study shows that the accuracy achieved in the experiments attains to the order of magnitude in 10~(-3).     

On the contribution of interference of electromagnetic and chromomagnetic dipole operators in the $$ \bar B $$ → Xsγ decay at O(αs2)

The contribution of c-quark loops into the interference of the electromagnetic and chromomagnetic dipole operators in the \(\bar B\) → X _s γ decay is calculated to O(α _s ² ) within the framework of the Standard Model (SM). Several new calculation techniques, such as Laporta’s automated algorithm, the second order decomposition method, and Mellin-Barnes representation, have been used.     

Determination of an upper limit for the mass of the τ-neutrino at LEP

An upper limit for the mass is determined through the kinematic reconstruction of the decay5 ^± in the OPAL detector at LEP. The limit is obtained using a new method based on the comparison of the two-dimensional distribution of energy and invariant mass of the five-pion system with expectations from different neutrino mass hypotheses. From a sample of five events surviving the selection criteria we obtain an upper limit of 74 MeV at 95% confidence level. It is the first measurement at LEP energies, where the larger average multiplicity of events makes the suppression of this background more robust compared to lower energies.     

Linear entropy dynamics of the field in the Jaynes－Cummings model with an intensity-dependent coupling in the dispersive approximation

We present the linear entropy dynamics of the field state in the dispersive cavity in the Jaynes－Cummings model with an intensity-dependent coupling in the dispersive approximation, and investigate the influence of dissipation on entanglement between the field and the atoms. We show that the coherence properties of the field are also affected by the cavity when the nonlinear process of the field interacting with the atoms with an intensity-dependent coupling is involved, and find that the dissipation constant, the intensity of the field and the atomic distribution angle have different influence on the coherence properties of the field.     

Automatic detection of the belt-like region in an image with variational PDE model

In this paper, we propose a novel method to automatically detect the belt-like object, such as highway, river, etc., in a given image based on Mumford-Shah function and the evolution of two phase curves. The method can automatically detect two curves that are the boundaries of the belt-like object. In fact, this is a partition problem and we model it as an energy minimization of a Mumford-Shah function based minimal partition problem like active contour model. With Eulerian formulation the partial differential equations (PDEs) of curve evolution are given and the two curves will stop on the desired boundary. The stop term does not depend on the gradient of the image and the initial curves can be anywhere in the image. We also give a numerical algorithm using finite differences and present various experimental results. Compared with other methods, our method can directly detect the boundaries of belt-like object as two continuous curves, even if the image is very noisy.     

Transitions Between Quantized Standing Waves at Interactions with an Atom in the Raman–Nath Regime

The interaction of an atom with an electromagnetic field induces transitions between its quantized modes, in which cos- and sin-standing waves are chosen as the basis for quantization. The number of photons in the modes were calculated in the Raman–Nath regime in the approximation of adiabatic following. It is shown that in the course of transitions an initially populated mode is generally not completely emptied, and the oscillating part of photons increases with the total number in the system.     

Observance of the energy flux balance at the boundary of a crystal for a wave incident at an angle of ϕ≠0, reflected wave, and two natural waves with arbitrary polarization ellipses refracted at angles of ψ1 and ψ2

The energy flux balance at the boundary of a gyrotropic transparent crystal is shown to be observed for arbitrary elliptical polarization of the incident wave.     

An Investigation of Three-Dimensional Construction Methods in the Micromachining of Silicon Surfaces with an Ultraviolet Laser

１ＩｎｔｒｏｄｕｃｔｉｏｎＲｅｃｅｎｔｄｅｖｅｌｏｐｍｅｎｔｓｉｎｍｉｃｒｏｏｐｔｉｃｓ，ｍｉｃｒｏｅｌｅｃｔｒｏｎｉｃｓａｎｄｍｉｃｒｏｍｅｃｈａｎｉｃｓｒｅｑｕｉｒｅｎｏｖｅｌａｎｄｕｎｉｑｕｅｐｒｏｄｕｃｔｉｏｎｔｅｃｈｎｏｌｏｇｉｅｓｔｏ...     

Detailed Investigation of Neutron–Neutron Angular Correlations in the Spontaneous Fission of $${}^{{252}}$$ Cf

Physics of Atomic Nuclei - New precise measurements of angular neutron–neutron ( $$nn$$ ) correlations in the spontaneous fission of $${}^{252}$$ Cf were performed with the aim of studying...     

Evolution of the Photon-number Probability Distribution in the System of a Three Level Atom with an Added Kerr-like Medium

ＥｖｏｌｕｔｉｏｎｏｆｔｈｅＰｈｏｔｏｎｎｕｍｂｅｒＰｒｏｂａｂｉｌｉｔｙＤｉｓｔｒｉｂｕｔｉｏｎｉｎｔｈｅＳｙｓｔｅｍｏｆａＴｈｒｅＬｅｖｅｌＡｔｏｍｗｉｔｈａｎＡｄｄｅｄＫｅｒｌｉｋｅＭｅｄｉｕｍＸＩＥＦａｎｇｓｅｎＬＥＩＭｉｎｓｈｅｎｇＧＵ...     

Hölder Continuity of the Rotation Number for Quasi-Periodic Co-Cycles in $${SL(2, \mathbb R)}$$

We prove two results on the rotation number of the skew-product system \({(\omega ,A):(\theta ,y)\in\mathbb T^d\times\mathbb R^2\mapsto (\theta +\omega ,A(\theta)y)\in\mathbb T^d\times\mathbb R^2,}\) where ω is Diophantine and \({A(\theta)\in SL(2, \mathbb R)}\) is homotopic to the identity. On the one hand, we prove that this function has the behavior of a \({\frac{1}{2}-}\) Hölder function. On the other, we show that the length of the gaps has a sub-exponential estimate which depends on its label given by the gap-labeling theorem. We give also an estimate of the complement of the spectrum. These results are obtained by studying the reducibility of the quasi-periodic co-cycle (ω , A).     

The reusability characteristics of LiF:Mg,Cu,P with a maximum intensity at 280 °C in an environment with elevated temperature

Efforts are aimed at finding a method that could serve TL dosimetric measurements in the range of low-dose but carried out in an environment with elevated temperature. The temperature at the position of the maximum intensity of LiF:Mg,Cu,P was about 280 °C when annealed at 460 °C. LiF:Mg,Cu,P with a maximum intensity at 280 °C should present good thermal stability. The TL intensity of LiF:Mg,Cu,P with a maximum intensity at 280 °C was about 54% of the standard LiF:Mg,Cu,P, it should have a minimum measurable dose in the range of micro-Gy. LiF:Mg,Cu,P with a maximum intensity at 280 °C could be re-used by the 660 °C/30 min annealing, followed by 270 °C/20 min, 240 °C/10 min and 460 °C/30 min. It's possible for LiF:Mg,Cu,P to be extended application for low dose test in an environment with elevated temperature.     

Determination of the factorized atomic part of the X-ray absorption cross section in the near-edge spectrum: Application to the analysis of structural changes in β zeolite with an increase in the aluminum content

A technique for determining the factorized atomic part σ_at(k) of the X-ray absorption cross section in the near-edge range of small photoelectron wave numbers k, based on the selection of this function from the experimental absorption spectrum of the atom in a compound, has been developed. This technique has been tested using the X-ray absorption near-edge structure (XANES) spectra of aluminum and silicon in a number of model compounds with known structure and applied to investigation of changes in the character of the short-range environment of a silicon atom in β zeolite with a variable Si/Al ratio. Use of the function σ_at(k) obtained by the developed technique in the ab initio calculation of the XANES spectra of silicon in a model β zeolite with Si/Al = 100 makes it possible to reduce the effect of the errors of the muffin-tin approximation on the fine structure of the calculated spectrum and substantiate the possibility of comparing relative changes in a certain spectral range with a change in the structure of the short-range environment of silicon in β zeolite with an increase in the aluminum content. On the basis of this approach, the formation of local distortions in the oxygen tetrahedron coordinating an ionized silicon atom with an increase in the aluminum content (decrease in the Si/Al ratio from 100 to 12) has been established.     

Production of the neutral top-pion πt^0 in association with a high-pw jet at the LHC＊

In the framework of the topcolor-assisted technicolor （TC2） model, we study the production of the neutral top-pion πt^0 in association with a high-pw jet at the LHC, which proceeds via the partonic processes gg→πt^0g, gq →πt^0q, qq→πt^0g, gb（b）→πt^0b（b）, and bb→πt^0g. We find that it is very challenging to detect the neutral top-pion πt^0 via the process pp → πt^0 ＋jet ＋ X＋ tt＋jet ＋X, while the possible signatures of πt^0 might be detected via the process pp→πt^0 ＋jet ＋ X→（tc＋tc）＋jet＋X at the LHC.     

Entanglement in the Ground State of an Isotropic Three-Qubit Transverse XY Chain with Energy Current

The ground state entanglement in an isotropic three-qubit transverse XY chain with energy current is analysed. A quantum phase transition from a no-energy-current phase to energy-current phase is found when the magnetic field changes. It has also been found that the ground state changes in company with the quantum phase transition.     

Precision measurements of strangeness photoproduction at threshold energies with the Crystal Ball at MAMI-C

The photoproduction of K＋ mesons from the nucleon provides important constraints on the nucleon excitation spectrum and at threshold energies challenges effective field theories based on chiral perturbation in the strange quark sector. Preliminary cross-section measurements for γ（P, K＋）A are presented at an unprecedented beam energy resolution. The data was collected at the MAMI-C facility in Mainz using the Crystal Ball Detector. A new method of K＋ detection was used in which the K＋ is tagged from its weak decay products in the detector crystals. This technique has application with other calorimeters at present and future hadron facilities.     

Application of the Wiener–Hopf method for describing the propagation of sound in cylindrical and rectangular channels with an impedance jump in the presence of a flow

Exact solutions to problems of the propagation of acoustic modes in lined channels with an impedance jump in the presence of a uniform flow are constructed. Two problems that can be solved by the Wiener- Hopf method—the propagation of acoustic modes in an infinite cylindrical channel with a transverse impedance jump and the propagation of acoustic modes in a rectangular channel with an impedance jump on one of its walls—are considered. On the channel walls, the Ingard–Myers boundary conditions are imposed and, as an additional boundary condition in the vicinity of the junction of the linings, the condition expressing the finiteness of the acoustic energy. Analytical expressions for the amplitudes of the transmitted and reflected fields are obtained.