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Precise knowledge of such fundamental quantity as the proton charge radius rp is extremely important both for the quantum chromodynamics (for quark-gluon structure) and for atomic physics (for atomic hydrogen spectroscopy). Yet the ambiguity in measuring rp persists for over a dozen of years by now—from the time when in 2010 the muonic hydrogen spectroscopy experiment yielded rp ≈ 0.84 fm in contrast to the form factor experiment by the Mainz group that produced rp ≈ 0.88 fm. Important was that this difference corresponded to about seven standard deviations and therefore was inexplicable. In the intervening dozen of years, more experiments of various kinds were performed in this regard. Nevertheless, the controversy remains, which is why several different types of new experiments are being prepared for measuring rp. In one of our previous papers, we pointed out the factor that was never taken into account by the corresponding research community: the flavor symmetry of electronic hydrogen atoms, whose existence was confirmed by four kinds of atomic or molecular experiments and also evidenced by two kinds of astrophysical observations. Specifically, in that paper there was discussed the possible presence of the second flavor of muonic hydrogen atoms (in the corresponding experimental gas) and its effect on the shift of the ground state of muonic hydrogen atoms due to the proton finite size. In the present paper we analyze the effect of the flavor symmetry of electronic hydrogen atoms on the corresponding elastic scattering cross-section and on the proton charge radius rp deduced from the cross-section. As an example, we use our analytical results for reconciling two distinct values of rp obtained in different elastic scattering experiments: 0.88 fm and 0.84 fm (which is by about 4.5% smaller than 0.88 fm). We show that if the ratio of the second flavor of hydrogen atoms to the usual hydrogen atoms in the experimental gas would be about 0.3, then the extraction of rp from the corresponding cross-section would yield by about 4.5% smaller value of rp compared to its true value. We also derive the corresponding general formulas that can be used for interpreting the future electronic and muonic experiments. [ABSTRACT FROM AUTHOR]

This paper presents a world-leading scintillation light yield among inorganic crystals measured from a 0.5 kg pure-CsI detector operated at 77 Kelvin. Scintillation photons were detected by two 2-inch Hamamatsu SiPM arrays equipped with cryogenic front-end electronics. Benefiting the light yield enhancement of pure-CsI at low temperatures and the high photon detection efficiency of SiPM, a light yield of 30.1 photoelectrons per keV energy deposit was obtained for X-rays and γ -rays with energies from 5.9 to 59.6 keV. Instrumental and physical effects in the light yield measurement are carefully analyzed. This is the first stable cryogenic operation of kg-scale pure-CsI crystal readout by SiPM arrays at liquid nitrogen temperatures for several days. The world-leading light yield opens a door for the usage of pure-CsI crystal in several fields, particularly in detecting the coherent elastic neutrino-nucleus scattering of reactor neutrinos. The potential of using pure-CsI crystals in neutrino physics is discussed in the paper. [ABSTRACT FROM AUTHOR]

This paper presents a detailed study of low energy positron scattering from formic acid, examining elastic scattering, electronic excitation and ionisation processes. Through detailed comparisons with previous experimental and theoretical data, it is clear that the picture for positron scattering from this target remains incomplete, with significant disagreement between experiment and theory in the comparisons of differential cross section data. Calculations of elastic electron scattering are unexpectedly in better agreement with the positron scattering experiments, and give some hints as to potential areas for improvement in the modelling of scattering for targets which tend to be dominated by dipole interactions. [ABSTRACT FROM AUTHOR]

The interior inverse elastic scattering problem is considered in this paper. The scattering in the cavity is illuminated by an time-harmonic elastic point source at fixed frequency. The boundary of the cavity is assumed to be a small and smooth perturbation of some circle. In this paper, we are interested in the reconstruction of the boundary according to the measured data on a closed curve inside the cavity. In implementation, we split the displacement field into compressional and shear waves by the Helmholtz decomposition. Then we use coordinate transformation, power series expansion based on perturbed parameters and Fourier expansion of corresponding power series coefficients to simplify the original boundary value problem to a successive sequence of one-dimensional boundary value problem. We linearize the inverse problem by eliminating the higher-order terms in the power series expansion; and design a reconstruction algorithm by the explicit relationship between the Fourier coefficients of the boundary function and the total field. In order to obtain better resolution, we also use a nonlinear correction method in the numerical experiments. The numerical results have shown the effectiveness and the stableness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, the scattering and vibration isolation of elastic waves from the open trench are analyzed and discussed in the time domain using the scaled boundary finite element method (SBFEM). Based on the theory of soil-structure interaction, the site with an open trench is decomposed into a near-field system and an infinite far-field system. The quadtree domain decomposition technique is employed for SBFEM mesh discretization of the near-field. The far-field is rigorously modeled by the displacement unit impulse response matrix. The obliquely plane elastic wave from the far-field is converted into a traction force acting on the near/far-field boundary. The time-space domain numerical model is established for elastic wave propagation in half-space with an open trench. Finally, through numerical examples to verify the effectiveness of the method of this paper, and parametric analyze the effect law of the incidence angle and the trench depth, etc., on the vibration isolation performance. [ABSTRACT FROM AUTHOR]

Purpose: The switching of motion states and grazing/sliding motion for an oscillator are typical dynamic phenomena in some discontinuous/non-smooth dynamical systems such as friction/vibro-impact systems with clearance. This work describes the behavior of discontinuous dynamics for a two-degree-of-freedom (2-DOF) frictional collision system with intermediate rigid constraint and unilateral elastic collision under periodic excitation by flow switching theory, where this kind of system considered in this paper can better reflect the actual working conditions of a class of mechanical vibration systems and is few researched at present. Methods: First, the physical model studied in this paper is introduced and analyzed in depth (such as motion state, motion equation, etc.). Second, based on the discontinuity/nonsmoothness of oscillator's movement, the absolute and relative phase planes of oscillator's movement are divided into multiple dynamic domains and dynamic boundaries such that the vector field in each dynamic domain is continuous. Third, according to the difference between the static friction coefficient and the dynamic friction coefficient of the system, the flow barrier which is generated on the velocity boundary and prevents the boundary flow from flowing to the domain is studied. Results: By means of the vector field and G-function, the criteria for the switching of each state of motion on the separation boundaries are obtained. And then, the conversions of some typical movements are more intuitively demonstrated through numerical simulation based on MATLAB software. A multi-body dynamics model of this 2-DOF system is developed in MSC Adams to help us visualize the actual dynamics behavior under real dimensional system parameters and compare it with the foregoing numerical simulation for a group of periodic motion data, and the results are nearly consistent. Conclusion: This work further improves the flow switching theory and brings a theoretical reference for multi-constrained mechanical systems. [ABSTRACT FROM AUTHOR]

In this paper, we have made a comparative study of α-α scattering using different phenomenological models like Morse, double Gaussian, double Hulthén, Malfliet-Tjon, and double exponential for the nuclear interaction, and atomic Hulthén as the screened Coulomb potential. The phase equations for S, D, and G channels have been numerically solved using the 5th -order Runge-Kutta method to compute scattering phase shifts (SPS) for the elastic scattering region consisting of energies up to 25.5 MeV. The model parameters in each of the chosen potentials were varied in an iterative fashion to minimize the mean absolute percentage error (MAPE) between simulated and expected SPS. A comparative analysis revealed that all the phenomenological models result in exactly similar optimized potentials with closely matching MAPE values for S, D, and G states. One can conclude that any mathematical function that can capture the basic features of two-body interaction will always guide the construction of optimized potentials correctly. [ABSTRACT FROM AUTHOR]

By extending the dipole Pomeron (DP) model, successful in describing elastic nucleon–nucleon scattering, to proton single diffractive dissociation (SD), we predict a dip-bump structure in the squared four-momentum transfer (t) distribution of proton's SD. Structures in the t distribution of single diffractive dissociation are predicted around t = − 4 GeV 2 at LHC energies in the range of 3 GeV 2 ≲ | t | ≲ 7 GeV 2 . Apart from the dependence on s (total energy squared) and t (squared momentum transfer), we predict also a dependence on missing masses. We include the minimum set of Regge trajectories, namely the Pomeron and the Odderon, indispensable at the LHC. Further generalization, e.g., by the inclusion of non-leading Regge trajectories, is straightforward. The present model contains two types of Regge trajectories: those connected with t -channel exchanges (the Pomeron, the Odderon, and non-leading (secondary) reggeons) appearing at small and moderate − t , where they are real and nearly linear, as well as direct-channel trajectories α (M 2) related to missing masses. In this paper, we concentrate on structures in t neglecting (for the time being) resonances in M 2 . [ABSTRACT FROM AUTHOR]

The paper is concerned with the problem of toppling propagation velocity in elastic, domino-like mechanical systems. We build on the work of Efthimiou and Johnson, who developed the theory of perfectly elastic collisions of thin rigid dominoes on a frictional foundation. This theory has been criticised for the lack of correspondence with the experimental observations, in particular, prediction of infinite propagation velocity for zero spacing between dominoes, as well as the inability to represent the collective nature of collisions in real domino systems. In our work we consider a more realistic scenario of dominoes of finite stiffness and obtain a theory of fast elastic domino waves, taking into account a limit velocity of the perturbation propagation in the system of dominoes. Moreover, finite collision time allows to extract dynamic quantities of collisions and establish upper and lower borders for domino separations where the theory could still be applied. Our discrete element simulations support our theoretical findings and shed light on the nature of collective interactions in the nearly-elastic domino chains. [ABSTRACT FROM AUTHOR]

In the present paper, a new technique is presented to study the problem of invertibility of unbounded block 3 × 3 operator matrices defined with diagonal domain. Sufficient criteria are established to guarantee our interest and to prove some interaction between such a model of an operator matrix and its diagonal operator entries. The effectiveness of the proposed new technique is shown by a physical example of an integro differential equation named the neutron transport equation with partly elastic collision operators. In particular, the obtained results answer the question in [H. Zguitti, A note on Drazin invertibility for upper triangular block operators, Mediterr. J. Math. 10 2013, 3, 1497–1507] and the conjecture in [A. Bahloul and I. Walha, Generalized Drazin invertibility of operator matrices, Numer. Funct. Anal. Optim. 43 2022, 16, 1836–1847]. [ABSTRACT FROM AUTHOR]

This paper is devoted to establishing the resonant modal expansion of the lowfrequency part of the scattered field for acoustic bubbles embedded in elastic materials. Due to the nanobubble with damping, the Minnaert resonance can be induced at certain discrete resonant frequencies, which forms the fundamental basis of effectively constructing elastic metamaterials via the composite material theory. There are two major contributions in this work. First, we ansatz a special form of the density, approximate the incident field with a finite number of modes, and then obtain an expansion with a finite number of modes for the acoustic-elastic wave scattering in the time-harmonic regime. Second, we show that the low-frequency part of the scattered field in the time domain can be well approximated by using the modal expansion with sharp error estimates. Interestingly, we find that the 0th mode is the main contribution to reconstruct the information of the low-frequency part of the scattered field. [ABSTRACT FROM AUTHOR]

The future Ricochet experiment aims to search for new physics in the electroweak sector by measuring the Coherent Elastic Neutrino-Nucleus Scattering process from reactor antineutrinos with high precision down to the sub-100 eV nuclear recoil energy range. While the Ricochet collaboration is currently building the experimental setup at the reactor site, it is also finalizing the cryogenic detector arrays that will be integrated into the cryostat at the Institut Laue Langevin in early 2024. In this paper, we report on recent progress from the Ge cryogenic detector technology, called the CryoCube. More specifically, we present the first demonstration of a 30 eVee (electron equivalent) baseline ionization resolution (RMS) achieved with an early design of the detector assembly and its dedicated High Electron Mobility Transistor (HEMT) based front-end electronics with a total input capacitance of about 40 pF. This represents an order of magnitude improvement over the best ionization resolutions obtained on similar phonon-and-ionization germanium cryogenic detectors from the EDELWEISS and SuperCDMS dark matter experiments, and a factor of three improvement compared to the first fully-cryogenic HEMT-based preamplifier coupled to a CDMS-II germanium detector with a total input capacitance of 250 pF. Additionally, we discuss the implications of these results in the context of the future Ricochet experiment and its expected background mitigation performance. [ABSTRACT FROM AUTHOR]

In Paper I of this series, the elastic collision was described via simultaneous processes, where the energy is conserved at any moment. In this paper, we critically review the kinetic theory of gases, which was developed based on Newtonian mechanics, and show that it violates the principle of the conservation of energy. By placing the energy conservation at the beginning of the deductive formalism, we derive the ideal gas law via equally strong simultaneous counter-processes at the walls, namely, momentum work and volume work. Several new insights into the state variables of an ideal gas are obtained: (i) pressure cannot be expressed via the kinetic energy of an ideal gas, and (ii) temperature can be interpreted as a particle-related (microscopic) state variable. The historical choice to set a zero point of the potential energy for a confined ideal gas needs to be corrected, and the internal energy of an ideal gas turns out to include more forms of energy than specified in the kinetic theory of gases. Finally, and importantly, we show that the process approach to an ideal gas and thus to collisions is experimentally confirmed. [ABSTRACT FROM AUTHOR]

Basic kinetic process of plasmas is studied by a first principle based N-body simulation. By confirming Coulomb collisional relaxation process, this paper is extended to investigate the dynamics of Debye shielding. Some of the key numerical techniques are discussed, including how to avoid singularities at the near encounter of two charged particles. Electron distribution function in Debye shielding is revealed, which deviates from conventional Maxwellian distribution function. [ABSTRACT FROM AUTHOR]

The drift velocity of a particle under a driving force has its roots in the theory of electrical conduction. Although it has been studied for over 100 years, it still yields surprises. At the heart of a particle's drift velocity is an interplay of classical, quantum, and statistical mechanics. Irreversibility and energy loss have been assumed as essential features of drift velocities and very little effort has been made to isolate the aspects of particle transport that are due to elastic mechanisms alone. In this paper, we remove energy loss and quantum mechanics to investigate the classical and statistical factors that can produce a drift velocity using only elastic scattering. A Monte Carlo simulation is used to model a particle in a uniform force field, subject to randomly placed scatterers. Time-, space-, and energy-dependent scattering models, with varied ranges of scattering angles, are investigated. A constant drift velocity is achieved with the time scattering model, which has a constant average time between scattering events. A decreasing drift velocity is observed for space and energy-dependent models. The arrival of a constant drift velocity has to do with a balance of momentum gained between collisions and momentum lost after a collision. [ABSTRACT FROM AUTHOR]

Optical model or coupled-channels calculation serves as an entrance to sophisticated calculation of nuclear data. It gives the optical quantities such as total, shape elastic scattering, absorption cross sections, direct inelastic scattering cross sections, angular distributions of elastic and inelastic scattering, and transmission coefficients for subsequent statistical model calculations. Traditionally, coupling of the elastic scattering channel to excited states of the target nucleus was ignored or treated with a simplified model such as rigid rotor or harmonic oscillator. It was a great contribution of Dr. Efrem Sh. Soukhovitsukii who has developed an excellent computation scheme which takes account of the low-lying collective nuclear structure in terms of the soft-rotator + vibrational model, and integrated it into the coupled-channels calculation. This methodology was realized as 2 computer codes, SHEMMAN and OPTMAN. In Japan, we had a fortuitous experience with him to employ this methodology in nuclear data evaluation, which started as a nuclear physics work to analyze neutron-scattering cross section of 12 C which were published as a series of 3 papers in Nuclear Physics A journal. After recognizing the usefulness of this methodology, it was applied to evaluation of nuclear data gradually and extensively, which resulted in obtaining awards of Atomic Energy Society of Japan (AESJ) by one of the authors (SK). This paper describes our collaborative works and recent findings on light-nuclei based on what he had developed. [ABSTRACT FROM AUTHOR]

The discrete event simulation with simultaneous events is discussed. Discrete models are treated as some points in the general space of models. The main topic of this paper is the convergence of sequences of continuous models to the corresponding discrete event model. It is pointed out that the discrete event models may represent some singularities in the space of models. This fact is related to the problem of validity of discrete event simulation. The models presented here are not the topic of the paper. These are known models, used as examples. The model of the "chicken game" and multiple elastic collisions are considered. It is shown that if a discrete event model is some special limit case of a sequence of continuous models with finite event duration, then that limit model is a singularity. It may provide results very different from the expected limit value of the results from the converging sequence of models. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations provide information on atomic displacement cascades due to the ionic collisions on the time scale of picoseconds and simultaneously account for the effects of crystal structure and temperature. Thus, molecular dynamics can help to understand the specific material behaviour during ion irradiation and make predictions for long-term neutron exposure as well. The latter is especially important for new generations of high-temperature reactors which use ceramics as construction materials. The paper presents the preliminary molecular dynamics simulations of argon irradiation of the SiC sample at very low energies, where mainly elastic collisions dominate, and two different sample temperatures are presented. The obtained results clearly illustrate the time-dependent reduction of the crystal defect number and the influence of the electronic stopping power. Additionally, the number of sustainable crystal defects depends largely on the sample temperature. [ABSTRACT FROM AUTHOR]

In this paper, some properties of resonances for multi-dimensional quantum walks are studied. Resonances for quantum walks are defined as eigenvalues of complex translated time evolution operators in the pseudo momentum space. For some typical cases, we show some results of existence or nonexistence of resonances. One is a perturbation of an elastic scattering of a quantum walk which is an analogue of classical mechanics. Another one is a shape resonance model which is a perturbation of a quantum walk with a non-penetrable barrier. [ABSTRACT FROM AUTHOR]

We report absolute elastic differential cross sections (DCSs) for electron collisions with phosphorus trifluoride, PF3, molecules (e- + PF3) in the impact energy range of 2.0-200 eV and over a scattering angle range of 10°-150°. Measured angular distributions of scattered electron intensities were normalized by reference to the elastic DCSs of He. Corresponding integral and momentum-transfer cross sections were derived by extrapolating the angular range from 0° to 180° with the help of a modified phase-shift analysis. In addition, due to the large dipole moment of the considered molecule, the dipole-Born correction for the forward scattering angles has also been applied. As a part of this study, independent atom model calculations in combination with screening corrected additivity rule were also performed for elastic and inelastic (electronic excitation plus ionization) scattering using a complex optical potential method. Rotational excitation cross sections have been estimated with a dipole-Born approximation procedure. Vibrational excitations are not considered in this calculation. Theoretical data, at the differential and integral levels, were found to reasonably agree with the present experimental results. Furthermore, we explore the systematics of the elastic DCSs for the four-atomic trifluoride molecules of XF3 (X = B, N, and P) and central P-atom in PF3, showing that, owing to the comparatively small effect of the F-atoms, the present angular distributions of elastic DCSs are essentially dominated by the characteristic of the central P-atom at lower impact energies. Finally, these quantitative results for e- - PF3 collisions were compiled together with the previous data available in the literature in order to obtain a cross section dataset for modeling purposes. To comprehensively describe such a considerable amount of data, we proceed by first discussing, in this paper, the vibrationally elastic scattering processes whereas vibrational and electronic excitation shall be the subject of our following paper devoted to inelastic collisions. [ABSTRACT FROM AUTHOR]

The main objective of this research is to study the properties of a billiard system in an unbounded domain with moving boundary. We consider a system consisting of an infinite rod (a straight line) and a ball (a massless point) on the plane. The rod rotates uniformly around one of its points and experiences elastic collisions with the ball. We define a mathematical model for the dynamics of such a system and write down asymptotic formulae for its motions. In particular, we determine existence and uniqueness of solutions. We find all possible grazing impacts of the ball. Besides, we demonstrate that for almost every initial condition, the ball goes to infinity exponentially fast, with the time intervals between neighboring collisions tending to zero. The approach developed in this paper is an original combination of methods of Billiards and Vibro-Impact Dynamics. It could be a base for studying more complicated systems of similar types. [ABSTRACT FROM AUTHOR]

Big data is a large set of data that is analyzed with the calculation to manifest myriad sources. Big data is capable of handling various challenges to processing huge amounts of data. To handle issues based on large-scale databases, a MapReduce framework is employed which provides robust and simple infrastructure for huge datasets. This paper proposes a novel Elastic collision seeker optimization based Faster R-CNN (ECSO-FRCNN) classifier for efficient big data classification. The proposed ECSO-FRCNN classifier is capable of handling missing attributes, and incremental learning and improves training performance effectively. As the proposed technique deals with large data samples, it necessitates the inclusion of the MapReduce framework. The adaption of MapReduce design in big data classification prevents the classification results from uncertainties such as data redundancy, misclassification, and storage issues. The proposed method is examined with three standard datasets, namely the skin segmentation dataset, mushroom dataset, and localization dataset, collected from the University of California, UCI machine learning repository. Finally, extensive experimental analysis is carried out for various parameters to depict the efficiency of the system. [ABSTRACT FROM AUTHOR]

In this paper, we extensively study the electronic structure, interactions, and dynamics of the (MgCs)+ molecular ion. The exchanges between the alkaline atom and the low-energy cationic alkaline earths, which are important in the field of cold and ultracold quantum chemistry, are studied. We use an ab initio approach based on the formalism of non-empirical pseudo-potential for Mg2+ and Cs+ cores, large Gaussian basis sets, and full-valence configuration interaction. In this context, the (MgCs)+ cation is treated as an effective two-electron system. Adiabatic potential energy curves and their spectroscopic constants for the ground and the first 20 excited states of 1,3Σ+ symmetries are determined. Furthermore, we identify the avoided crossings between the electronic states of 1,3Σ+ symmetries. These crossings are related to the charge transfer process between the two ionic limits, Mg/Cs+ and Mg+/Cs. Therefore, vibrational-level spacings and the transition and permanent dipole moments are presented and analyzed. Using the produced potential energy data, the ground-state scattering wave functions and elastic cross-sections are calculated for a wide range of energies. In addition, we predict the formation of a translationally and rotationally cold molecular ion (MgCs)+ in the ground-state electronic potential energy through a stimulated Raman-type process aided by ion–atom cold collision. In the low-energy limit (<1 mK), elastic scattering cross-sections exhibit Wigner law threshold behavior, while in the high-energy limit, the cross-sections act as a function of energy E go as E−1/3. A qualitative discussion about the possibilities of forming cold (MgCs)+ molecular ions by photoassociative spectroscopy is presented. [ABSTRACT FROM AUTHOR]

This paper presents a joint experimental and theoretical study of positron scattering from furan. Experimental data were measured using the low energy positron beamline located at the Australian National University and cover an energy range from 1 eV to 30 eV. Cross sections were measured for total scattering, total elastic and inelastic scattering, positronium formation, and differential elastic scattering. Two theoretical approaches are presented: the Schwinger multichannel method and the independent atom method with screening corrected additivity rule. In addition, our data are compared to corresponding electron scattering results from the same target with a number of significant differences observed and discussed. [ABSTRACT FROM AUTHOR]

Resonance is a remarkable feature in elastic scattering and the resonant states of eâ€"C60 scattering are benchmarked using Shannon entropy in the present work. The resonant wavefunction, total cross-section, partial cross-sections, and scattering phase shifts are calculated for the eâ€"C60 scattering to review the localization properties owing to resonance. Three different model interaction potentials are used in the paper to simulate the environment of the C60 shell; annular square well, Gaussian annular square well, and Lorentzian potential. This paper aims to establish a relationship between the Shannon entropy and resonant properties linked with e + C60 scattering. This work introduces the Shannon entropy as an indicator of resonance in elastic scattering and it unveils the susceptibility of entropic properties to the nature of the model potential. [ABSTRACT FROM AUTHOR]

This paper concentrates on an interaction scattering problem between the time-harmonic electromagnetic waves and an unbounded periodic elastic medium. The uniqueness results of the interaction problem are established for small frequencies or all frequencies except a discrete set in both the absorbing and nonabsorbing medium, and then the existence of solutions is derived by the classical Fredholm alternative. The perfectly matched layer (PML) method is proposed to truncate the unbounded scattering domain to a bounded computational domain. We prove the well-posedness of the solution for the truncated PML problem, where a homogeneous boundary condition is imposed on the outer boundary of the PML. The exponential convergence of the PML method is established in terms of the thickness and parameters of the PML. The proof is based on the PML extension and the exponential decay properties of the modified fundamental solution. [ABSTRACT FROM AUTHOR]

The propagation characteristics of elastic waves in polycrystalline materials depend not only on grain size, but also on grain size distribution. In this paper, based on Weaver's polycrystalline scattering model, two grain size distribution models, namely the truncated lognormal distribution and the fractal distribution based on fractal dimension, are considered. At the same time, the ultrasonic attenuation of polycrystalline materials is studied by considering the existence of finite interval of grain size. The grain size of the classical lognormal distribution ranges from zero to infinity, which is inconsistent with the actual situation. The present work modifies Turner's study based on the lognormal distribution and compares the numerical results with Turner's. The numerical results obtained from the two kinds of distributions show that the scattering attenuation in the Rayleigh scattering region is affected by both the grain size distribution and the average grain size. In the transition scattering region, the attenuation of P-wave scattering is related to the average grain size and size distribution, while the attenuation of S-wave scattering is mainly affected by the average grain size. In the stochastic scattering region, the scattering attenuation is mainly affected by the average grain size and is not sensitive to the grain size distribution. Moreover, the numerical results also show that the difference of scattering attenuation due to the grain size distribution is most obvious in the Rayleigh scattering region. [ABSTRACT FROM AUTHOR]

The two-phase emission detector RED-100 with 130 kg of liquid xenon as a working medium has been exhibited at a distance of 19 m from the core of the VVER-1000/320 nuclear power reactor at the fourth power unit of the Kalinin Nuclear Plant Power in 2021–2022. Due to the high sensitivity of the detector for weak ionization signals (down to single electrons), the detector has been used to search for the elastic coherent scattering of reactor electron antineutrinos off xenon nuclei. However, the observation of ~30 kHz single-electron noise did not quite allow for an effective selection of the useful events. The next experiment with the RED-100 detector is considered to be arranged with 62 kg of liquid argon as a working medium. The advantages of this approach are discussed in this paper. [ABSTRACT FROM AUTHOR]

We systematically investigate the relationship between the nuclear structure and reaction in the 10Be nucleus using a theoretical framework. The structure of the 10Be nucleus is constructed with a cluster model based on a microscopic viewpoint. In this paper, the 10Be nucleus is prepared with different structures by manipulating the parameters of an effective nucleon–nucleon interaction. The nuclear structure and expectation values of physical quantities are drastically changed by the modification. We summarize such changes and show the effects on the elastic and inelastic scatterings for proton and 12C targets in the microscopic coupled-channel calculation. Of especial interest, we recently reported the visualization of the dineutron correlation in 10Be on proton inelastic scattering in [Phys. Rev. C 104 , 034613 (2021)]. In this preceding work, we found that changing the degree of dineutron correlation in 10Be leads to drastic changes of the inelastic cross section for the 2 |$_2^+$| state. The development (or breaking) of the dineutron correlation is governed by the strength of the spin–orbit interaction of the structure calculation. However, in the previous work, some of the realistic physical points were missing, for example, the binding energy (BE). Therefore, we reconstruct the 10Be nucleus by adjusting the effective nucleon–nucleon interaction to obtain a reasonable BE of the ground state. With this improvement, we again discuss the dineutron correlation in the 10Be nucleus. We reconfirm the way to measure the degree of development (or breaking) of the dineutron cluster structure: its sensitivity to the inelastic cross section of the 2 |$_2^+$| state of 10Be. Subject Index cluster model, folding model, dineutron correlation, effective nucleon-nucleon interaction. [ABSTRACT FROM AUTHOR]

In a special run of the LHC with β ⋆ = 2.5 km, proton–proton elastic-scattering events were recorded at s = 13 TeV with an integrated luminosity of 340 μ b - 1 using the ALFA subdetector of ATLAS in 2016. The elastic cross section was measured differentially in the Mandelstam t variable in the range from - t = 2.5 · 10 - 4 GeV 2 to - t = 0.46 GeV 2 using 6.9 million elastic-scattering candidates. This paper presents measurements of the total cross section σ tot , parameters of the nuclear slope, and the ρ -parameter defined as the ratio of the real part to the imaginary part of the elastic-scattering amplitude in the limit t → 0 . These parameters are determined from a fit to the differential elastic cross section using the optical theorem and different parameterizations of the t-dependence. The results for σ tot and ρ are σ tot (p p → X) = 104.7 ± 1.1 mb , ρ = 0.098 ± 0.011. The uncertainty in σ tot is dominated by the luminosity measurement, and in ρ by imperfect knowledge of the detector alignment and by modelling of the nuclear amplitude. [ABSTRACT FROM AUTHOR]

Reducing ear damage is the key to improving the quality of maize harvests. In order to reduce the impact and damage of the ear caused by the ear snapping mechanism, this paper proposes a method to convert ear deformation energy during collision into elastic potential energy in the ear snapping mechanism. According to the above method, a low-damage maize snapping mechanism was designed. In order to verify the feasibility of energy conversion in reducing damage, the dynamic model of the contact between the ear and the snapping plate was established, and a dynamic simulation analysis was carried out based on the finite element method (FEM). In order to obtain better parameters for the improved mechanism, a test rig was established, after which a performance test was carried out on the test rig. The results showed that the primary and secondary order that affected the ear damage rate was the rotational speed of the snapping roller, the spring stiffness and the forward speed. The data processing software Design Expert was used to optimize the parameters, it was concluded that when the rotational speed was 805 r·min−1, the forward speed was 1.29 m·s−1, the spring stiffness was 33.5 N·mm−1, the model predicted that the ear damage rate was 0.023%. Therefore, this paper could provide further reference for research into maize low-damage ear snapping technology. [ABSTRACT FROM AUTHOR]

This paper concerns a time-domain scattering problem of elastic plane wave by a rigid obstacle, which is immersed in an open space filled with homogeneous and isotropic elastic medium in two dimensions. A new compressed coordinate transformation is developed to reduce the scattering problem into an initial boundary value problem in a bounded domain over a finite time interval. The well-posednesss is established for the reduced problem. This paper adopts Galerkin method to prove the uniqueness results and employs energy method to derive stability results for the scattering problem. Furthermore, we achieve a priori estimate with explicit time dependence. [ABSTRACT FROM AUTHOR]

The (3 + 1) -dimensional [ (3 + 1) -d] Mel'nikov equation describes an interaction between long-wave and short-wave packets in three-spatial dimensions, which is the coupling of (3 + 1) -d Kadomtsev–Petviashvili [KP] equation and nonlinear Schrödinger [NLS] equation. In this paper, its P T -symmetric version is introduced, and we call it (3 + 1) -d nonlocal Mel'nikov equation. General soliton solutions, including crossed soliton and parallel soliton, are presented in terms of KP hierarchy reduction method. Furthermore, the semi-rational solutions consisting of lumps and solitons are also constructed. These semi-rational solutions are elastic collision. However, the corresponding semi-rational solution of most nonlocal two-dimensional systems describes the inelastic collision between the lump waves and the solitons under the same conditions. Additionally, a new way to get the rational solution of Mel'nikov equation is given by reducing the semi-rational solution of the (3 + 1) -d nonlocal Mel'nikov equation. These novel dynamics have never been reported in (3 + 1) -d nonlocal systems. Moreover, it broadens our research field and inspires us to explore the mysteries of higher-dimensional nonlocal systems. [ABSTRACT FROM AUTHOR]

A great deal of attention is being paid by researchers to the multilevel modeling of complex gas-phase physicochemical processes occurring in the atmosphere, during combustion, and in plasma-chemical installations. One of the most important microscopic processes determining the transfer of radiation in these systems is the broadening of spectral lines in collisions of radiating atoms with atoms in the ground state. In this paper, we propose a formulation of the unified Franck-Condon theory of the broadening of spectral lines in gases in terms of the theory of slow atomic collisions and nonadiabatic transitions. This makes it possible to select the most efficient channels leading to the broadening of collisions based on the form of the adiabatic potential curves of the colliding atoms and, on this basis, apply fairly simple models developed in the theory of nonadiabatic transitions. As an example of using this approach, the center and wings of the of the spectral line contour of the Ar(3P1) → Ar(1S0) emission of excited argon atoms in their own gas are calculated. [ABSTRACT FROM AUTHOR]

Neutrino elastic scattering observation with NaI (NEON) is an experiment designed to detect neutrino-nucleus coherent scattering using reactor electron antineutrinos. NEON is based on an array of six NaI(Tl) crystals with a total mass of 13.3 kg, located at the tendon gallery that is 23.7 m away from a reactor core with a thermal power of 2.8 GW in the Hanbit nuclear power complex. The installation of the NEON detector was completed in December 2020, and since May 2021, the detector has acquired data at full reactor power. Based on the observed light yields of the NaI crystals of approximately 22, number of photoelectrons per unit keV electron-equivalent energy (keVee), and 6 counts/kg/keV/day background level at 2–6 keVee energy, coherent elastic neutrino-nucleus scattering (CE ν NS) observation sensitivity is evaluated as more than 3 σ assuming 1-year reactor-on and 100 days reactor-off data, 0.2 keVee energy threshold, and 7 counts/keV/kg/day background in the signal region of 0.2 - 0.5 keVee. This paper describes the design of the NEON detector, including the shielding arrangement, configuration of NaI(Tl) crystals, and associated operating systems. The initial performance and associated sensitivity of the experiment are also presented. [ABSTRACT FROM AUTHOR]

In this paper, vortex solitons are produced for a variety of 2D spinning quantum droplets (QDs) in a P T -symmetric potential, modeled by the amended Gross–Pitaevskii equation with Lee–Huang–Yang corrections. In particular, exact QD states are obtained under certain parameter constraints, providing a guide to finding the respective generic family. In a parameter region of the unbroken P T symmetry, different families of QDs originating from the linear modes are obtained in the form of multipolar and vortex droplets at low and high values of the norm, respectively, and their stability is investigated. In the spinning regime, QDs become asymmetric above a critical rotation frequency, most of them being stable. The effect of the P T -symmetric potential on the spinning and nonspinning QDs is explored by varying the strength of the gain–loss distribution. Generally, spinning QDs trapped in the P T -symmetric potential exhibit asymmetry due to the energy flow affected by the interplay of the gain–loss distribution and rotation. Finally, interactions between spinning or nonspinning QDs are explored, exhibiting elastic collisions under certain conditions. [ABSTRACT FROM AUTHOR]

In this paper, we study the low-energy d - α elastic scattering within the two-body cluster effective field theory (EFT) framework. The importance of the d (α , α) d scattering in the 6 Li production reaction leads us to study this system in an effective way. In the beginning, the scattering amplitudes of each channel are written in a cluster EFT with two-body formalism. Using the effective range expansion analysis for the elastic scattering phase shift of S, P and D partial waves, the unknown EFT low-energy coupling constants are determined and the leading and next-to-leading orders EFT results for the phase shift in each channel are presented. To verify the accuracy of the results, we compare experimental phase shift and differential cross section data with obtained results. The accuracy of the EFT results and consistency with the experimental data indicate that the EFT is an effective approach for describing low-energy systems. [ABSTRACT FROM AUTHOR]

This paper presents the calculation of new elastic scattering cross sections for the simulation of electron interactions in liquid water. The calculations are based on the "ELastic Scattering of Electrons and Positrons by neutral Atoms" code, which adopts a Dirac partial wave analysis. A Muffin-tin potential was used in order to account for the liquid-phase of water, and the optical parameters of the correlation-polarization and the inelastic absorption potentials were optimized against vapour-phase water data. The differential and total elastic scattering cross sections calculated in the present work show a global agreement with the experimental data. The impact of these elastic scattering cross sections on the transport of electrons in liquid water was evaluated by track-structure simulations of range, dose-point-kernel, microdosimetric spectra, and ionization clustering using the Geant4-DNA simulation toolkit. The results are compared against those obtained with the elastic scattering models already available in Geant4-DNA and are discussed. [ABSTRACT FROM AUTHOR]

This paper presents a study of both the elastic and inelastic scattering of a deuteron beam on 13 C at laboratory energy of 18 MeV. The first 10 excited states of the carbon isotope were studied in terms of single-particle and collective models of excitation. Experimental cross sections were obtained by the well-known Δ E–E method. Elastic scattering data were analyzed using an optical model including a nucleus–nucleus interaction potential, while inelastic scattering data were processed using the coupled-channels approach. For the single-particle model, the spectroscopic amplitudes were obtained through calculations of the large-scale shell model with the YSOXT effective NN-potential. A double folding potential was obtained for the d + 13 C system. A comparison of model calculations with the experimental cross sections was demonstrated. The extracted deformation parameters and calculated spectroscopic information are shown in tables. The ability of the collective model to describe all excited states was demonstrated by good agreement when comparing the calculated cross sections in the collective model and experimental data. The single-particle model turned out to be significant only for the excited state of 3.09 MeV. The dominant role in the formation of the corresponding cross section is played by the 12 C ground state core with the 2 S 1 / 2 neutron. [ABSTRACT FROM AUTHOR]

Because of the Internet of Things (IoT) and wearable devices, information obtained is subject to cyber attacks, making intrusion detection an essential component. The increased number of attacks on IoT devices exposes them to ongoing exploitation and data theft. Mirai, denial of Service (DoS), scan, etc are the major types of attacks conducted on IoT. Traditional attack detection algorithms have more disadvantages like lack of adaptability in all scenarios, low local minima computational complexity, etc. Thus developing a method that is suitable for all environments and has good convergence speed is taken as the motivation of this study. This paper presents a novel Symbiotic Organisms Search Algorithm (SOSA) optimized Faster region-based convolutional neural network (FRCNN) for attack detection and data type classification. The data to be stored in the cloud is analyzed whether they have restricted access, confidential, or unclassified. Depending upon the variety of data, the Optimal homomorphic encryption (OHE) approach is provided for security. The key selection process is done by an Elastic Collision Seeker Optimization Algorithm (ECSOA) which offers secure access to the data owner and prevents the data from unauthorized access. The model is optimized using the algorithm which improves the feature extraction performance. The effectiveness of the proposed model in attack detection is evaluated using two datasets namely the CSE-CIC-ID2018 dataset and the IoTID20 dataset. When compared to the existing techniques, the proposed model offers optimal performance in terms of multiclass attack detection. [ABSTRACT FROM AUTHOR]

In this paper, we report on the 6 Li + 1 6 O system to which the crystal model (CM), the coupled reaction channel method (CRC), and continuum discretized coupled channel (CDCC) method were applied in addition to the distorted waves-Born approximation (DWBA), which was also applied to the 6 Li + 1 6 O system. Also, CM is folded with inelastic scattering. The analysis of the experimental data was performed simply with elastic and inelastic scattering in a first step. Then transfers have been studied like pp, nn, dd, p p + n n and 1 0 B using the CRC method. The CRC method was used to study many suggested combinations of transfers with elastic scattering. The analyses were performed for 6Li elastically scattered from 1 6 O in the energy range of 13–50 MeV. The cluster structure of 6 Li ≡ 4 He + 2 H has been examined during the CDCC method in addition to the breakup of the weakly bound structure of the same nucleus. A dynamic polarization potential (DPP) was used at E ( 6 Li) = 3 0 MeV. A comparison between different models was performed. A general agreement was found between the experimental data and the proposed theoretical methods. [ABSTRACT FROM AUTHOR]

An incoming elastodynamic wave impinges on an elastic obstacle is embedded in an infinite elastic medium. The objective of the paper is to examine the subsequent elastic fields scattered by and transmitted into the elastic obstacle. By applying a boundary-field equation method, we are able to formulate a nonlocal boundary problem (NBP) in the Laplace transformed domain, using the field equations inside the obstacle and boundary integral equations in the exterior elastic medium. Existence, uniqueness and stability of the solutions to the NBP are established in Sobolev spaces for two different integral representations. The corresponding results in the time domain are obtained. The stability bounds are translated into time domain estimates that can serve as the starting point for a numerical discretization based on Convolution Quadrature. [ABSTRACT FROM AUTHOR]

This paper is concerned with the inverse elastic scattering problem for a random potential in three dimensions. Interpreted as a distribution, the potential is assumed to be a microlocally isotropic Gaussian random field whose covariance operator is a classical pseudodifferential operator. Given the potential, the direct scattering problem is shown to be well-posed in the sense of distributions by studying the equivalent Lippmann--Schwinger integral equation. For the inverse scattering problem, we demonstrate that the microlocal strength of the random potential can be uniquely determined with probability one by a single realization of the high frequency limit of the averaged compressional or shear backscattered far-field pattern of the scattered wave. The analysis employs the integral operator theory, the Born approximation in the high frequency regime, the microlocal analysis for the Fourier integral operators, and the ergodicity of the wave field. [ABSTRACT FROM AUTHOR]