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In this work, the angular distribution of atmospheric cosmic muons is studied using PYTHIA8 simulations, comparing it to the experimental data. The standalone code in PYTHIA8 consists of an atmosphere of only nitrogen molecules. Here, the standalone code has been augmented adding oxygen molecules with a relative abundance of 78:22 (Nitrogen:Oxygen) to resemble a more realistic atmosphere. The vertical flux intensity ( I μ (θ)) of cosmic muons varies with zenith angle as a function of cos n θ , where θ is the zenith angle and n is the exponent term. The vertical flux intensity of cosmic muons has been characterized as a function of zenith angle (θ), momentum (p) and energy (E). Simulations are compared to the experimental results found in the literature and to the measurements performed at the surface laboratories of SINP (Kolkata) and JUSL (Jadugoda) at two different latitudes and altitudes in May 2024. The integrated vertical muon flux ( I μ (0)) and the exponent term (n) are extracted by fitting each experimental dataset. The simulated vertical flux intensity ( I μ (θ)) as a function of the zenith angle (θ) of cosmic muons shows a good level of agreement with the spectral shape of our experimental data as well as with that from literature. This study highlights the relevance of PYHTIA8 in the context of air-shower simulations, improving its predictive power by incorporating a more realistic atmospheric model. [ABSTRACT FROM AUTHOR]

The critical points were calculated using the Dirac equation and real optical potential model, in addition to calculating differential, integrated elastic, transfer momentum and viscosity cross sections, and Sherman function for elastic scattering of Potassium atoms at the range 4 to 150 eV and in the angular range θ = 0–180°. We obtained two critical positions (38.1 eV, 141.1°) and (128.1 eV, 120.2°) at these positions we obtained the highest polarisation of spin, and the amplitude of the spin–flip is greater than the amplitude of the direct scattering. This study is considered the first calculation of the critical points in the differential cross sections for electron scattering by potassium atom. [ABSTRACT FROM AUTHOR]

The emission angular distributions, the transverse momentum distributions and the temperature parameters of projectile fragments produced in fragmentation of 2 8 Si on C target at 736 A MeV are measured. It is found that the scattering angle of primary silicon ions is smaller than the emission angle of their fragments. The average value and the width of the angular distribution and the transverse momentum distribution are increased with the decrease of the charge of projectile fragments. The cumulative squared transverse momentum distribution of projectile fragments can be well fitted by a single Rayleigh distribution, which indicates that the projectile fragments are emitted from a single temperature emission source. Most of the temperature parameters of projectile fragments emission source are in the range of 2–5 MeV, which does not obviously depend on the charge of the projectile fragments. [ABSTRACT FROM AUTHOR]

Laser-induced fluorescence spectroscopy (LIFS) is actively used for remote sensing of atmospheric aerosols and is currently one of the most sensitive and selective techniques for determining small concentrations of substances inside particles. The use of high-power femtosecond laser sources for LIFS-based remote sensing of aerosols contributes to the development of new-generation fluorescence atmospheric lidars since it makes it possible to overcome the energy threshold for the nonlinear-optical effects of multiphoton absorption in particles and receive the emission signal at long distances in the atmosphere. Our study is aimed at the development and experimental demonstration of the technique of nonlinear laser-induced fluorescence spectroscopy (NLIFS) based on the remote excitation of aerosol fluorescent emission stimulated by a spatially structured high-power femtosecond laser pulse. Importantly, for the first time to our knowledge, we demonstrate the advances in using stochastically structured plasma-free intense light channels (postfilaments) specially formed by the propagation of femtosecond laser radiation through a turbulent air layer to improve NLIFS efficiency. A multiple increase in the received signal of two-photon-excited fluorescence of polydisperse-dyed aqueous aerosols by the structured postfilaments is reported. [ABSTRACT FROM AUTHOR]

Using the Monte Carlo method, the impact of the angular distribution of the electron source on the dose distribution for the 2.5 MeV ELV electron accelerator was explored. The experiment measured the 3-D dose distribution in the irradiation chamber for electron energies of 1.0 MeV and 2.5 MeV. The simulation used the MCNP6.2 code to evaluate three angular distribution models of the source: a mono-directional beam, a cone shape, and a triangular shape. Of the three models, the triangular shape with angles θ = 30°, φ = 0° best represents the angle of the scan hood through which the electron beam exits. The MCNP6.2 simulation results demonstrated that the triangular model is the most accurate representation of the angular distribution of the electron source for the 2.5 MeV ELV electron accelerator.

The results of calculating the energy spectra of protons transmitted and reflected from thin layers of gold are presented. The simulation results are compared with experimental data. It is shown that the stopping measurement results are affected by such factors as the multiple scattering, the geometry of the experiment, and the morphology and roughness of the target. An analysis of the angular dependence for particles passing through a thin film makes it possible to obtain information about the interaction potential between a particle and a solid. The obtained results on the potential agree with the data from experiments on the reflection of particles from the surface of a solid and differ markedly from the data on the potential determined from the scattering of particles in the gas phase. [ABSTRACT FROM AUTHOR]

Laser-induced fluorescence spectroscopy (LIFS) is actively used for remote sensing of atmospheric aerosols and is currently one of the most sensitive and selective techniques for determining small concentrations of substances inside particles. The use of high-power femtosecond laser sources for LIFS-based remote sensing of aerosols contributes to the development of new-generation fluorescence atmospheric lidars since it makes it possible to overcome the energy threshold for the nonlinear-optical effects of multiphoton absorption in particles and receive the emission signal at long distances in the atmosphere. Our study is aimed at the development and experimental demonstration of the technique of nonlinear laser-induced fluorescence spectroscopy (NLIFS) based on the remote excitation of aerosol fluorescent emission stimulated by a spatially structured high-power femtosecond laser pulse. Importantly, for the first time to our knowledge, we demonstrate the advances in using stochastically structured plasma-free intense light channels (postfilaments) specially formed by the propagation of femtosecond laser radiation through a turbulent air layer to improve NLIFS efficiency. A multiple increase in the received signal of two-photon-excited fluorescence of polydisperse-dyed aqueous aerosols by the structured postfilaments is reported.

The angular distribution of photons emitted at interaction of low-energy electrons with atoms of noble gases is investigated. The angular asymmetry of the bremsstrahlung cross section is significant and strongly depends on the electron and photon energies. The effect of polarization radiation is considered. It is shown that this effect is noticeable even below the electroluminescence threshold, in contrast to the generally accepted point of view. In the case of argon, the account for the polarization radiation improves the agreement between the predictions and the available experimental data for the yield of bremsstrahlung photons. [ABSTRACT FROM AUTHOR]

A simple analytical formulas for estimation of the yield and angular distribution of neutrons from thick targets would be useful for calculating the biological protection of heavy ion accelerators with energy (1–6) MeV/nucleon. The results of the calculation with this formulas were compared with those obtained using the LISE++ and FLUKA programs as well as with the available experimental data. As a result, it can be stated that the proposed calculation method can be used for quick assessment. The deviation of the results of such calculations from more accurate ones does not exceed a factor of two, which is comparable with the deviations in the calculation of biological shielding due to a variety in the protection properties of the materials used or in their thickness. [Display omitted] [ABSTRACT FROM AUTHOR]

We present an analytical method to study the angular distribution of THz radiation driven by two-colour laser-induced microplasma in nitrogen gas. Directionally dependent temporal waveforms of the radiated THz pulse is calculated. To do so, we have extended the photo-current model to calculate three-dimensional distribution of the photo-induced current from which the far-field THz radiation is computed. We have also studied the effect of optical polarization state and phase difference on the angular distribution of radiation. Our study shows that for two orthogonally-polarized colours, not only THz polarization state, but also the angular distribution of THz radiation is mostly influenced by the second optical harmonic. The possibility of rotating the angular radiation pattern around the axis of the laser propagation is illustrated for circularly-polarized laser drivers by changing the optical phase difference. [ABSTRACT FROM AUTHOR]

Angular distribution of the differential cross section of α 40Ca elastic scattering has been investigated in the anomalous large angle scattering (ALAS) region by a nonlocal velocity dependent optical potential with surface term. The geometrical potential parameters were fixed and the depths of the potential were determined by fitting elastic angular distribution over the energy range (23–53.9 MeV). The real and the imaginary parts of the optical potential used here are of Woods–Saxon form factors. An energy dependence of the potential depths has been investigated at fixed geometrical potential parameters.

Knowledge distillation as a broad class of methods has led to the development of lightweight and memory efficient models, using a pre-trained model with a large capacity (teacher network) to train a smaller model (student network). Recently, additional variations for knowledge distillation, utilizing activation maps of intermediate layers as the source of knowledge, have been studied. Generally, in computer vision applications, it is seen that the feature activation learned by a higher-capacity model contains richer knowledge, highlighting complete objects while focusing less on the background. Based on this observation, we leverage the teacher's dual ability to accurately distinguish between positive (relevant to the target object) and negative (irrelevant) areas. We propose a new loss function for distillation, called angular margin-based distillation (AMD) loss. AMD loss uses the angular distance between positive and negative features by projecting them onto a hypersphere, motivated by the near angular distributions seen in many feature extractors. Then, we create a more attentive feature that is angularly distributed on the hypersphere by introducing an angular margin to the positive feature. Transferring such knowledge from the teacher network enables the student model to harness the teacher's higher discrimination of positive and negative features, thus distilling superior student models. The proposed method is evaluated for various student–teacher network pairs on four public datasets. Furthermore, we show that the proposed method has advantages in compatibility with other learning techniques, such as using fine-grained features, augmentation, and other distillation methods. [ABSTRACT FROM AUTHOR]

Accelerated protons and C-ions are used by means of radiation therapy (RT) for cancer treatment for over 50 years. Monte Carlo simulations with FLUKA transport code were performed to simulate particle therapy with either protons or C-ions at a given radiation therapy energy. The average Human Body (AHUBO) Phantom has been used to create a human head model (sphere of 8 cm radius). The AHUBO head was placed in (0, 0, 0) the Cartesian system of the Flair graphical interface of FLUKA, and the ion source at Z=-30 cm apart from the centre. The primary beams consisted of 107 protons of 100 MeV and 107 C-ions with 190 MeV/u, energies pertaining to a Bragg peak positioned in the centre of the AHUBO head model (coinciding with the position of the pituitary). The Angular distribution of secondary neutrons with respect to the incident direction of the primaries was scored with a USRBDX for angles 0-180 degrees of solid angle (step 15 degrees). Results showed that there are three typical maxima in the neutron spectra, one thermal and two high energy (HE) peaks. The position and the intensity of the HE peaks change with the change of the solid angle for both incident particle type simulations. The neutron fluence near the margin of the 8 cm radius sphere (region inwards) for the treatment with primary protons was estimated to be in the range of 10-5cm-2, while in the case of treatment with primary C-ions, the fluence was one order of magnitude greater (10-4). [ABSTRACT FROM AUTHOR]

Experimental data concerning projectile and target fragmentation is limited, increasing the uncertainty on the dose in the entrance channel in particle therapy treatments. The FOOT experiment measures nuclear fragmentation cross sections with two complementary detectors. The performance of the FOOT nuclear emulsion detectors in identifying the charge of nuclear fragments has recently been studied using 16 O beams at 200 and 400 MeV/n , directed at carbon and polyethylene targets. This work extends the previous analysis, comparing experimental data and FLUKA Monte Carlo predictions, focusing on the angular distribution and relative abundances of fragments with Z ≤ 5 originating from the interactions of a 400 MeV/n oxygen beam with a carbon target. [ABSTRACT FROM AUTHOR]

This work reports atomic alignment of silver after L3-subshell ionization in collisions with electrons in energy range 10–50 keV, i.e., (3∼15)EL3, where EL3(=3.351 keV) is the binding energy of electrons in the L3-subshell. The characteristic spectra are measured at different emission angles from -40∘ to 40∘ intervals of 10∘. The angular dependence of X-ray emission is studied for Lα(L3→M4,5) and Lβ2(L3→N5) lines respectively, using a thin target. The anisotropy parameter β is determined from two angular distribution measurements of differential X-ray intensity ratios dI(Lα,θ)/dI(Lβ1,θ) and dI(Lβ2,θ)/dI(Lβ1,θ). This served to reduce the experimental uncertainties. For the derivation of the alignment factor A20 we took into account the Coster–Kronig (CK) correction factor κ, which allows for, CK transition probabilities fij among L-subshells. We found that the sign of A20 is mostly negative, and the influence of CK transition is significant for large alignment parameters. In addition, the experimental results are compared to theoretical predictions within the framework of Plane Wave Born Approximation (PWBA) and reasonable agreement is found in the energy range studied in the present work. Simultaneously, good scaling property of atomic alignment is demonstrated when we consider also previous experimental results. Our measurement extends the scaled velocity V (=vp/vt) to a range of 1∼4 for medium-Zt targets, and the results of atomic alignment can provide a fundamental testing ground for ionization models.

Dynamics and radiation of a relativistic charged particle moving in a linear restoring force field is studied. Solutions to the equations of motion are presented in a compact form in terms of Jacobi elliptic functions. The intensity of radiation, its angular distribution and radiation spectrum of a relativistic oscillator are investigated. It is shown that, unlike a non-relativistic oscillator, the maximum intensity is emitted not at the turning points, but at some intermediate points of the particle’s trajectory. The emission spectrum consists of lines at frequencies that are multiples of the oscillation frequency of the oscillator. As the oscillator energy increases, the number of harmonics in the spectrum increases. The maximum in the spectrum of highly relativistic oscillator occurs on high numbers of harmonics. [ABSTRACT FROM AUTHOR]

The process of T-lymphocyte migration involves a complex interplay of chemical and mechanical signals. Mechanotransduction mechanisms in T lymphocytes enable them to efficiently navigate through diverse architectural and topographical features of the dynamic tissue macro- and micro-niches encountered during immune responses. Piezo1 mechanosensors are crucial for driving optimal T-cell migration by driving actin-cytoskeletal remodeling. Chemokine-stimulated T lymphocytes demonstrate significant asymmetry or polarity of Piezo1 and actin along the cell axis. The establishment and maintenance of polarity in migrating cells are paramount for facilitating coordinated and directional movements along gradients of chemokine signals. Live-cell imaging techniques are widely employed to study the trajectories of migrating cells. Our approach expands upon current methodologies by not only tracking migrating cells but also imaging fluorescently labeled cellular components. Specifically, our method enables measurement of protein enrichment in the front and rear halves of the moving cell by analyzing the temporal direction of cell trajectories, subsequently bisecting the cell into front-back halves, and measuring the intensities of the fluorescent signals in each cell half at each time frame. Our protocol also facilitates the quantification of the angular distribution of fluorescent signals, enabling visualization of the spatial distribution of signals relative to the direction of cell migration. The protocol describes the examination of polarity in chemokine-treated Jurkat cells transfected with Piezo1-mCherry and actin-GFP constructs. This approach can be extended to live-cell imaging and polarity assessment of other fluorescently labeled proteins. Key features • This experimental protocol allows real-time imaging of Jurkat cells expressing two fluorescent proteins (Piezo1 mCherry and actin-GFP). • Measures cell polarity by examining spatial enrichment of Piezo1 and actin proteins within the front and rear halves of a moving Jurkat cell. • The protocol enables analysis of cell polarity in 2D tracks of moving cells. • Polarity analysis includes measuring fluorescent signal intensities in front-rear halves of a moving cell and calculation of signal polarization angles relative to the cell trajectory., Competing Interests: Competing interestsThe authors declare no competing financial interests., (©Copyright : © 2024 The Authors; This is an open access article under the CC BY-NC license.)

Nuclear Reaction Analysis (NRA) is employed to perform depth profiling of the light elements (carbon, nitrogen, oxygen …) in the heavy element substrates. To conduct the analysis, the availability and reliability of the respective differential cross-sections are among crucial factors to achieve the reliable results. In this work, we made a theoretical attempt to calculate the angular distribution of the transfer reaction (stripping reaction) 16O (d,p0)17O reaction at 1.3 and 1.6 MeV energies in the lab frame, which are usable in NRA. Moreover, the optical potential parameters, which are obtained through the work, can be utilized by the global optical potentials.

It has been shown that this method is quite suitable for surface studies and diagnostics of many component materials. The values of the azimuthal angle of distribution of Ne, Ar and Xe ions scattered from InGaP (001) are obtained. The relationship between the spatial variables of the scattered beam (mainly azimuthal angular spectra) and the type of ions has been established. The correlation between focusing properties of surface semichannel with a type of bombardment ion at the different angle of incidence has been shown.

Using the tagged neutron method at the "TANGRA" facility at Frank Laboratory of Neutron Physics of the Joint Institute for Nuclear Research based on the ING-27 standard neutron generator, a study of the 14.1 MeV inelastic neutron scattering reaction on different nuclei was carried out. The angular distributions of g-quanta accompanying inelastic neutron scattering on atomic nuclei were measured. This article presents a GEANT4-based program that allows calculating the interaction of fast neutrons with matter and simulating the experiment and also presenting the results of the experiment in a convenient and visual form. Using the written program, optimal target parameters were determined. The algorithm used by the program is given in this work. The general description of the experimental installation, data collection and processing systems is given.

A study of the reaction of inelastic scattering of 14.1 MeV neutrons by 23 Na nuclei was carried out at the TANGRA facility using the tagged neutron method. In this work, the energies of visible . transitions are determined, the yields of . -quanta are obtained, the angular distributions of . -quanta for 23 Na are measured. The results obtained are in good agreement with the data of other published experimental works.

The angular distributions of various spectral components of terahertz radiation generated by filament plasma are measured in a wide range of numerical apertures NA of the laser beam from 0.003 to 0.1. It is shown that propagation angles of terahertz radiation are inversely proportional to the square root of the terahertz frequency. It is shown that an increase in the numerical aperture of the laser beam leads to an increase in propagation angles of terahertz radiation in the entire range of observed frequencies. [ABSTRACT FROM AUTHOR]

Atomic alignment of Au ions with L 3 -subshell ionization by H+ and He2+ ions impact is reported for low incident velocity range, i.e., (0.06-0.11) ▪ for H+ and (0.04-0.08) ▪ for He2+ ions. Experimental results are compared with PWBA and SCA models. It is demonstrated that PWBA model cannot predict the measured values well for both projectiles. For SCA model, it can aptly anticipate the experimental outcomes when subjected to H+ impact., while it overestimates the measured alignment (absolute value) for He2+ ions impact. Discrepancies for He2+ ions impact are ascribed to utilization of the CK transition coefficients determined for single ionization, while multiple ionization occurring in the practical situation. Moreover, magnetic sub-state ionization cross sections σ (3 2 , 3 2) and σ (3 2 , 1 2) are determined with the measured alignment parameter A 20 , and the results are further explained by taking into account collision dynamics and spatial distribution of the m = 0 and m = 1 wavefunctions. • Robust connection between P 2 (cos θ) and intensity ratios is demonstrated. • Anisotropy of L β 2 is twice that of L α across different collision scenarios. • SCA reliably predicts proton impact outcomes. • Multiple ionization occurs even in ultra-low energy regimes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Angular thickness and composition profiles of Ba x Sr 1-x TiO 3 (x = 0.2) thin films in PED. • Forward shaped peaks in PED like in PLD for film thickness profiles. • Measurable thickness up to 80-90° for major axis and 25° for minor axis. • The film composition depends on the element and background gas used. The angular thickness and composition profiles of thin films obtained by irradiating a Ba x Sr 1-x TiO 3 (x = 0.2) target with a pulsed electron beam were investigated by Rutherford backscattering spectrometry for argon and oxygen background gases at a pressure of about 10-2 mbar. A "semi-sphere" holder was used, resulting in a fixed target to substrate distance of about 40 mm. The film thickness profiles have forward shaped peaks, with measurable thickness up to 80-90° for major axis and 25° for minor axis, and presents similar trend for both argon and oxygen background gas. The analysis of the congruent transfer of the elements from the target as a function of the angle showed that the film composition is not uniform over this wide angular range and differs with respect of the ablated target depending on the element used and on background gas. [ABSTRACT FROM AUTHOR]

The convergence performance of nonlinear acceleration methods for the method of characteristics (MOC) with flat source (FS) approximation (FS MOC) or linear source (LS) approximation (LS MOC) is numerically investigated by focusing on the spatial and angular approximations in the acceleration calculations. The convergence of nonlinear acceleration depends on the consistency of the calculation models between the higher-order and lower-order (acceleration) methods. The convergence of four acceleration methods is evaluated to clarify the relationship between model consistency and convergence performance. These methods consist of FS or LS for the spatial source distribution and P1 or discrete angle for the angular distribution, i.e., (1) FS analytic coarse mesh finite difference (ACMFD) acceleration (FS ACMFD), (2) LS ACMFD, (3) FS angular-dependent discontinuity factor MOC (ADMOC) acceleration (FS ADMOC), and (4) LS ADMOC. The ACMFD and ADMOC accelerations are based on P1 and discrete angle approximations, respectively. The FS MOC and LS MOC are considered higher-order methods. The FS MOC and LS MOC with five acceleration methods, i.e., the aforementioned four acceleration methods and the conventional coarse mesh finite difference acceleration method, are used to perform fixed-source calculations in one-group one-dimensional homogeneous slab geometry, and the spectral radii are numerically evaluated. The numerical results indicate that (1) the nonlinear acceleration methods that are unconditionally stable for FS MOC also show similar convergence properties for LS MOC in one-dimensional slab geometry; (2) better convergence is observed when the consistency of higher- and lower-order models is high; and (3) when a coarse mesh is optically thick, the spatial homogenization degrades the convergence performance, even if spatial and angular approximations are consistent between the higher- and lower-order models. [ABSTRACT FROM AUTHOR]

The article examines the angular distribution of cosmic ray intensity and identifies the triads using two different empirical formulas for their distribution. The total absorption coefficient of soft and hard components was measured. [ABSTRACT FROM AUTHOR]

The advent of mini-light-emitting diodes (mini-LEDs) represents a recent advancement in display technology. The biggest advantage of mini-LEDs over traditional backlight LED panels is that the LED array facilitates the local dimming of light intensity. This paper presents a large-view-angle (LVA) GaN-based mini-LED chip with batwing angular light distribution. By placing a translucent layer on the mini-LED, the angular light-intensity distribution can be modified from the Lambertian type to that resembling a batwing using translucent sublayer pairs. Compared to conventional mini-LEDs, the proposed mini-LED chip requires fewer LEDs and a shorter light-diffusing distance to maintain good uniformity without additional lens packaging. Further, the increased sublayer pair count in the translucent layer affords an increase in the radiation half-power angle from 137.5° to 173.2°. This increases the half-power angle of the mini-LED array from 47.4% to 89.1%. The findings of this study demonstrate significant potential for use in the development of ultrathin backlight panels, which are finding commercial utility in modern television designs. This work should provide the applications solution in mini-LED backlit and wide color gamut RGB backlight display.

Molecular frame photoelectron angular distributions (MFPADs) are measured in electron-ion momentum imaging experiments and compared with complex Kohn variational calculations for carbon K-shell ionization of carbon tetrafluoride (CF4), ethane (C2H6) and 1,1-difluoroethylene (C2H2F2). While in ethane the polarization averaged MFPADs show a tendency at low energies for the photoelectron to be emitted in the directions of the bonds, the opposite effect is seen in CF4. A combination of these behaviors is seen in difluoroethylene where ionization from the two carbons can be distinguished experimentally because of their different K-shell ionization potentials. Excellent agreement is found between experiment and simple static-exchange or coupled two-channel theoretical calculations. However, simple electrostatics do not provide an adequate explanation of the suggestively simple angular distributions at low electron ejection energies.

The ion energies and fluxes in the high power impulse magnetron sputtering plasma from a Nb target were analysed angularly resolved along the tangential direction of the racetrack. A reactive oxygen-containing atmosphere was used as such discharge conditions are typically employed for the synthesis of thin films. Asymmetries in the flux distribution of the recorded ions as well as their energies and charge states were noticed when varying the angle between mass-energy analyser and target surface. More positively charged ions with higher count rates in the medium energy range of their distributions were detected in +EB than in -EB direction, thus confirming the notion that ionisation zones (also known as spokes or plasma bunches) are associated with moving potential humps. The motion of the recorded negatively charged high-energy oxygen ions was unaffected. NbOxthin films at different angles and positions were synthesised and analysed as to their structure and properties in order to correlate the observed plasma properties to the film growth conditions. The chemical composition and the film thickness varied with changing deposition angle, where the latter, similar to the ion fluxes, was higher in +EB than in -EB direction.

The ion energies and fluxes in the high power impulse magnetron sputtering plasma from a Nb target were analysed angularly resolved along the tangential direction of the racetrack. A reactive oxygen-containing atmosphere was used as such discharge conditions are typically employed for the synthesis of thin films. Asymmetries in the flux distribution of the recorded ions as well as their energies and charge states were noticed when varying the angle between mass-energy analyser and target surface. More positively charged ions with higher count rates in the medium energy range of their distributions were detected in +EB than in -EB direction, thus confirming the notion that ionisation zones (also known as spokes or plasma bunches) are associated with moving potential humps. The motion of the recorded negatively charged high-energy oxygen ions was unaffected. NbOxthin films at different angles and positions were synthesised and analysed as to their structure and properties in order to correlate the observed plasma properties to the film growth conditions. The chemical composition and the film thickness varied with changing deposition angle, where the latter, similar to the ion fluxes, was higher in +EB than in -EB direction.

Neutron scattering from a copper sample was measured at Rensselaer Polytechnic Institute utilizing the quasi-differential method. The measurement spanned the energy range from 0.5 to 20 MeV using the high-energy scattering system and from 2 keV to 0.5 MeV using the new mid-energy scattering system. Copper was selected as a material of interest to measure due to large discrepancies between experiments and simulations of the Zeus benchmark. The Zeus benchmark consists of a copper reflected highly enriched uranium system, and the angular distribution of copper scattering was thought to potentially be the cause of the discrepancy. The copper measurements found differences in the scattering response particularly in the incident energy region from 1 to 2 MeV for the high-energy measurement and from 2 to 4 keV in the mid-energy system. These differences are particularly noticeable at angles near 90 deg in the high-energy system and back angles in the mid-energy system. Additionally, for ENDF/B-VIII.0 there is a large discrepancy at the forward angle in the energy range around 0.5 MeV. For these reasons, a new evaluation of copper scattering utilizing these results is recommended and perhaps could help to improve the agreement with the Zeus benchmarks. [ABSTRACT FROM AUTHOR]

Разработка программных генераторов расчета случайных величин соответсвующих основным угловым распределениям на окружности, фрактальных броуновских движений (ФБД) на окружности, поверхности и сфере с применением численных методов, метода обратной функции и спектрального метода фильтрации ФБД.

The present work is dedicated to study of the possibilities of improving the production method of 11C and 18F medical isotopes using a linear electron accelerator. Experimental studies of 11C and 18F isotopes production by the photonuclear technique were carried out in [1]. Various targets were irradiated by bremsstrahlung photons following by measurements targets’ activities. This experimental research has been carried out in the energy range from 10 to 40 MeV. The current work studies an angular distribution of bremsstrahlung photons in order to estimate the possibilities of producing maximum achievable levels of medical isotopes 18F and 11С activities. The angular distribution of bremsstrahlung photons is an important property of the irradiation stand which contains an assembly of targets. This important property allows designing necessary changes in the target assembly setup used to produce medical isotopes. The research presented in the current work was done as a computer simulation. The computer software package ‘KIPT’ was developed in С++ programming language, using the Geant4 toolkit in order to obtain the angular distribution of bremsstrahlung photons. Experimental setup materials as well as structural elements positions were defined in the DetectorConstruction class of our program. The parameters of an electron beam were defined in the PrimaryGeneratorAction class. The electron beam diameter was defined as 8 mm, energy Ее=36.7 MeV, corresponding to the real experiment carried out at the “Accelerator” Science and Research Establishment of Kharkiv Institute of Physics and Technology [1]. Models of physical processes occurring while the electron beam crosses the target assembly were defined in the PhysicsList class. All classes and modules necessary for the analysis of simulation results were included to our program together with visualization modules. Visualization modules use the OpenGL graphics library and the Qt5 software to represent the relative position of experimental setup parts and to visualize particle trajectories. As a result of this work, the angular distributions were obtained for the beam of electrons and bremsstrahlung photons directly before the target. This result will allow target assembly parameter optimization for optimal production of medical isotopes by the photonuclear technique.

We calculate the angular distribution of cosmic rays at a given point of the heliosphere under the assumption that the incoming flux from outer space is isotropic. The static magnetic field is shown to cause no anisotropy provided that the observation point is situated out of the trapped particle area. We consider a coronal ejection model in the form of a static cylinder with an axial homogeneous magnetic field inside. We calculate angular distribution samples in the trapped particle area (inside the cylinder) and show that there is a certain cone of directions with a reduced flux. For the same model with the moving cylinder, the angular distribution samples are calculated for different positions of the observation point outside the cylinder. Anisotropy of order of the ejection to light velocity ratio is shown to arise. The calculated samples are in qualitative agreement with URAGAN muon hodoscope data.

High resolution and wide color gamut are two key requirements for novel display technologies. Owing to the distinguishing advantages over conventional displays, such as intrinsic wide color gamut and the possibility to achieve high resolution, quantum dot light-emitting diodes (QLED) have drawn considerable attention in recent years. On the other hand, indium phosphide quantum dots (InP QDs) have shown a great potential as a replacement for cadmium selenide (CdSe) QDs in display applications due to the inherent toxicity of cadmium-based QDs. In this study, we investigate a top-emission InP-based green QLED with optimized angular distribution. By adjusting the electrical and optical architecture, the device exhibits improved properties with a maximum current efficiency of 30.1 cd/A and a narrowed full width at half maxima (FWHM)of 31 nm, which are the best results ever reported to our knowledge. [ABSTRACT FROM AUTHOR]

The Vlasov–Maxwell (VM) equations have been solved by the forward semi-Lagrangian (FSL) method to calculate the argon ion beam angular distribution in the dense plasma focus (DPF) device. The validity of the VM employment was investigated through the Dreicer field, the mean free path, and the Debye length of the plasma pinch. The simulations have shown that the ion beams were emitted in a direct way at the initial pressures of 10 and 20 Pa. The ion beam angular distribution expanded for pressures bigger than 20 Pa. It has been shown that this was because the radial component of the electric field inside the pinch was increased and the axial component of the electric field was decreased by increasing the initial pressure of the working gas. The places of the ion beam micro-sources (hotspots) have been illustrated by means of the ion and electron density profiles. [ABSTRACT FROM AUTHOR]

Angular distributions of atoms sputtered from a copper target under 5‐keV Kr+ bombardment at normal incidence were simultaneously and independently studied by experiments and computer simulation. The sputtered particles are collected on a Mylar™ foil placed around the target. Deposited particles on the substrate were analyzed by optical transmission spectroscopy. The surface roughness of the irradiated target was studied by atomic force microscopy, surface profilometry, and scanning electron microscopy. The experimental results were compared with the simulated angular distributions (programs OKSANA, SDTrimSP, and SRIM) and were found to be in reasonable agreement. In all cases, the angular distribution of sputtered particles showed an over‐cosine shape, which may be associated with noncompensated scattering of ejected particles by surface atoms when exiting the target. The results obtained are compared with the data from the literature. [ABSTRACT FROM AUTHOR]

When setting up physical experiments involving the use of the polarization properties of synchrotron radiation (SR) or a monoenergetic photon beam, detailed calculation of the spectral angular distribution of SR and its polarization components is of interest. Consideration of the electron beam size shows that in real conditions the radiation propagating in the plane of the equilibrium orbit will not be completely polarized, and the shape and dimensions of the angular distribution of radiation will be distorted. The motion of electrons in the uniform magnetic field and SR of the beam of relativistic particles in the storage ring of "NESTOR" are considered. The effect of the size of the electron beam with the energy of E=225 MeV in the 6-dimensional space on the formation of images of the flux of quanta of SR is analyzed. It is shown that the main contribution to the formation of images is made by the two-dimensional distribution of particles along the vertical direction axis and vertical oscillations. A software simulation code has been developed, the use of which made it possible to simulate the process of optical image formations by the flux of SR quanta (Этого предложения нет в русской аннотации). The formation of images of the radiation of electrons with an energy of E=225 MeV with change in the longitudinal distance L to the registration plane is considered. It is determined that at small longitudinal distances the main contribution to the image is made by the vertical distribution of particles in the beam. With an increase in the basic distance L, the contribution of the distribution of particles over vertical oscillations increases, which becomes decisive for large L value. Numerical simulation of image formation has been carried out. For the base distance of 300 cm and beam parameters with the vertical root mean square size of 0.2 mm and a vertical root mean square size of 0.15 mrad, the family of angular distributions is presented in the form of two-dimensional histograms for wavelengths , , , where , is the critical wavelength of SR. The dimensions of the optical window are obtained, the size of which makes it possible to reliably register the entire flux of SR quanta for the indicated registration characteristics.