Oscillation Parameters Research Articles

KM3NeT/ARCA: Status of construction and recent physics results

KM3NeT is a multi-site detector devoted to the detection and study of cosmic neutrinos and their sources in the Universe, and to the measurement of the neutrino oscillation parameters. Two underwater detectors are under construction in the Mediterranean Sea, ARCA (Portopalo di Capo Passero, Italy) and ORCA (Toulon, France), optimised respectively for neutrinos in the energy range of 1 TeV–100 PeV and 10 GeV–10 TeV. The mass construction of the detectors has started, and a long-term plan for the completion is in place. At the time of writing this article, 21 (14) detection units are already in operation in the ARCA (ORCA) site from a total of 230 (115). In these proceedings, the major milestones achieved for the construction of the ARCA telescope are discussed. The main physics results obtained with ARCA, in its partial configurations are reported. Finally, an overview of the expected performances of the full detectors will be given.

Simulation of a tubular cultivator rack of tillage machines under static and dynamic loads

Curved tubes of non-circular cross section are widely used in various fields of technology. The change in the planned operating modes of various technological processes is associated with the wear of the executing mechanisms, which is caused by unstable frequencies and amplitudes of oscillations. Thus, the issue of determining the oscillation parameters of these elements becomes more significant. The technique and results of tests for stresses, displacements and frequencies of natural oscillations of a tubular cultivator tine made in the form of a curved tube of various sections (mainly flat-oval with an inverse ratio of semiaxes) in the ANSYS software package are presented, the maximum allowable loads and the effect of a rigid tip on oscillation frequencies are determined.

ДОСЛІДЖЕННЯ НЕРЕЗОНАНСНИХ КОЛИВАНЬ СИСТЕМИ «ТЕЛЕСКОПІЧНИЙ ГВИНТ – СИПКЕ СЕРЕДОВИЩЕ»

In the article it is substantiated the value of the angular speeds of rotation of the auger screw, which leads to the breakdown of its lateral vibrations. The dependences describing the law of change of amplitude or natural frequency at slowly variable length of the telescopic screw are deduced. Based on the Van der Paul’s method, in the developed system differential equations are obtained that determine the laws of change of amplitude and frequency of the wave process in the system of a telescopic propeller. It is established that for nonresonant oscillations for this system the main parameters of bending oscillations are a continuous flow of bulk medium - the screw does not depend on its small torsional oscillations and external periodic perturbation. The analysis of the given regression equations shows that to reduce the torque of the auger it is necessary to reduce the frequency of its rotation and the angle of the conveyor. The constructive diagram and the results of theoretical calculations for assessing the influence of constructive-kinematic parameters on the torque indicators of the telescopic screw conveyor are presented.

Regulation of the Natural Oscillations Parameters of a Building Spatial Frame in the LIRA Software

Introduction. In recent years many researchers have become interested in applying the various types of finite element method to studying of the buildings oscillation problems. In recent decades the finite element method is being successfully used for natural oscillations analysis along with the physical modeling. The scaled physical modeling and experimental approaches are also suitable for solving the complex problems. The main aim of our research is to identify the dependence of dynamic characteristics of a building frame on geometric characteristics of the frame elements. The objective of this research is to make an analysis and overview of the topic, to determine the scientific deficit, to conduct numerical and experimental studies, to formulate conclusions, to model and analyse the results. The scientific novelty consists in the possibility to use the obtained data on building frame natural oscillations depending on the geometric characteristics of the frame elements as an optimal rigidness ratio. The practical significance of the research consists in development of specific analytical relations for choosing a building frame design solution with an optimal natural frequencies parameter to be used in design and construction practice.Materials and methods. The creation and calculation of the finite element model was carried out in the LIRA software package.Results. As a result of calculation the frequencies and periods of building frame natural oscillations were obtained.Discussion and conclusions. Based on the results of the building natural oscillations analysis the conclusion was made that by changing the frame elements rigidity it’s possible to select its dynamic characteristics to find the optimal design solution of structures.

Measurement of proton-carbon forward scattering in a proof-of-principle test of the EMPHATIC spectrometer

The next generation of long-baseline neutrino experiments will be capable of precision measurements of neutrino oscillation parameters, precision neutrino-nucleus scattering, and unprecedented sensitivity to physics beyond the Standard Model. Reduced uncertainties in neutrino fluxes are necessary to achieve high precision and sensitivity in these future precise neutrino measurements. New measurements of hadron-nucleus interaction cross sections are needed to reduce uncertainties of neutrino fluxes. We report measurements of the differential cross-section as a function of scattering angle for proton-carbon interactions with a single charged particle in the final state at beam momenta of 20, 30, and 120 GeV/c. These measurements are the result of a beam test for EMPHATIC, a hadron-scattering and hadron-production experiment. The total, elastic and inelastic cross-sections are also extracted from the data and compared to previous measurements. These results can be used in current and future long-baseline neutrino experiments, and demonstrate the feasibility of future measurements by an upgraded EMPHATIC spectrometer.

Structurally Stable Subharmonic Regime of a Driven Quantum Josephson Circuit

Driven quantum nonlinear oscillators, while essential for quantum technologies, are generally prone to complex chaotic dynamics that fall beyond the reach of perturbative analysis. By focusing on subharmonic bifurcations of a harmonically driven oscillator, we provide a recipe for the choice of the oscillator's parameters that ensures a regular dynamical behavior independently of the driving strength. We show that this suppression of chaotic phenomena is compatible with a strong quantum nonlinear effect reflected by the confinement rate in the degenerate manifold spanned by stable subharmonic orbits.

Entanglement Dynamics of Coupled Quantum Oscillators in Independent NonMarkovian Baths.

This work strives to better understand how the entanglement in an open quantum system, here represented by two coupled Brownian oscillators, is affected by a nonMarkovian environment (with memories), here represented by two independent baths each oscillator separately interacts with. We consider two settings, a 'symmetric' configuration wherein the parameters of both oscillators and their baths are identical, and an 'asymmetric' configuration wherein they are different, in particular, a 'hybrid' configuration, where one of the two coupled oscillators interacts with a nonMarkovian bath and the other with a Markovian bath. Upon finding the solutions to the Langevin equations governing the system dynamics and the evolution of the covariance matrix elements entering into its entanglement dynamics, we ask two groups of questions: (Q1) Which time regime does the bath's nonMarkovianity benefit the system's entanglement most? The answers we get from detailed numerical studies suggest that (A1) For an initially entangled pair of oscillators, we see that in the intermediate time range, the duration of entanglement is proportional to the memory time, and it lasts a fraction of the relaxation time, but at late times when the dynamics reaches a steady state, the value of the symplectic eigenvalue of the partially transposed covariance matrix barely benefit from the bath nonMarkovianity. For the second group of questions: (Q2) Can the memory of one nonMarkovian bath be passed on to another Markovian bath? And if so, does this memory transfer help to sustain the system's entanglement dynamics? Our results from numerical studies of the asymmetric hybrid configuration indicate that (A2) A system with a short memory time can acquire improvement when it is coupled to another system with a long memory time, but, at a cost of the latter. The sustainability of the bipartite entanglement is determined by the party which breaks off entanglement most easily.

Schlieren imaging and spectroscopic approximation of the rotational-vibrational temperatures of a microwave discharge igniter with a resonating cavity.

A microwave discharge igniter (MDI) with a resonating cavity was developed and optimized for practical applications in an internal combustion engine. In contrast to the typical microwave ignition, the resonating cavity of the MDI induces a discharge through dielectric resonance. Its source of microwave (MW) is a 2.45GHz semiconductor oscillator that is capable of numerous oscillation patterns. To verify and demonstrate the optimum ignition performance and combustion, we varied the oscillation parameters (signal factors) of the MW to optimize the performance of the MDI using the Taguchi method. Plasma spectroscopy was used for ignition condition analysis. Two sets of microwave pulses, a first pulse followed by a second set of pulse bursts, were used to ignite a propane-air fuel. The flame kernel growth rate and O I species generation were used as the response outputs, which were obtained, respectively from Schlieren imaging and emission spectroscopy experiments. The extended pulse periods and higher MW pulse numbers of the second set of pulses improved the response outputs of the MDI. To further analyze the effect of MW oscillation patterns on plasma properties and performance, measurements were done on MW superimposed operation with the high-voltage ignition from spark plugs. The MW transmission on a typical spark plug enhanced the air plasma ignition. Higher input MW energy and more extended MW pulse widths results in increased spectral intensity and radical generation of OH, O, and N 2. An inverse relation between the temperature and spectral intensity functions of the MW pulse width was observed, which was attributed to the cutoff density of the MW-enhanced plasma.

Tuning structural, optical, and dispersion functions of polystyrene via addition of meso-tetraphenylporphine manganese (III) chloride towards optoelectronic applications

Using a standard casting procedure, a polymeric composite of polystyrene (PS) and 5,10,15,20-tetraphenyl-21H,23H-porphine manganese (III) chloride (MnTPPCl) has been created. The structural alteration in the PS matrix brought on by MnTPPCl filling is confirmed by X-ray diffraction (XRD). According to vibrational groups that defined the prepared samples, the main distinctive peaks were found using Fourier transform infrared (FTIR). After filling, the majority of these absorption intensities have randomly varied from their values in the virgin polymer. Furthermore, new peaks at 1230 and 3642 cm−1 appeared and steadily increased with the increase in MnTPPCl content. Changes in the main vibrational bands in the FTIR spectra indicated the interaction of the composite components. The optical properties of the PS/MnTPPCl composite were investigated utilizing measurements of transmittance and reflectance. The absorption coefficient spectra demonstrate the emergence of new peaks (372–618 nm) after filling, which can be related to π→π* orbital transition of MnTPPCl. The optical energy gaps for the indirect and direct allowed transition were found to decrease with increasing MnTPPCl contents. A normal dispersion was found in the wavelength range of 830–2500 nm and an anomalous dispersion in the wavelength range of 190–830 nm, according to an analysis of the refractive index n. Calculations were made for the oscillator parameters, including oscillator and dispersion energies. The possibility of their employment in optoelectronic devices is implied by the reduction of the optical energy gap and the rise in refractive index caused by the addition of MnTPPCl.

Analysis of pressure oscillation and structural parameters on the performance of deflector jet servo valve

The performance of deflector jet servo-valve is highly affected by the flow field characteristics in the pilot stage of the deflector jet servo-valve. This research used the large eddy simulation method to study the pressure pulsation characteristics of the front stage flow field of DJSV, which has a high significance for the reasonable design of DJSV and the suppression of self-excited oscillation. The geometric model of the three-dimensional flow field of the jet pilot stage of the servo valve deflection plate was established. LES method was used to analyze the influence of the geometric parameters of the jet outlet, amplifier and receiving port on the flow field distribution characteristics of the pre-stage. The results show that pressure oscillation is highly affected by the inlet pressure. Structure optimization is a good solution for decreasing pressure oscillation in deflector jet servo valve.

PROCESSING OF BULK AND ROD MATERIALS IN COMBINED VESSELS

Purpose and task is making research on the dynamics of a vibrating installation to process tubular materials and the kinematics of their movement (circulation) in hemispherical chambers.
 Methodology. To achieve the target goal, an expert assessment of existing approaches to methods of processing bulk and rod materials in air and liquid environments has been carried out.
 Research methods. Using vibrations for heat treatment of bulk and tubular materials makes it possible to intensify the heat exchange process, significantly reduce processing time, save fuel and electricity consumption, improve product quality, reduce costs on maintenance and environmental protection. The materials of theoretical studies on vibrating machine dynamics under different types of working body oscillations and the number of vibration drives are presented. Analytical dependences of vibration parameters have been obtained.
 The main results. Using vibrations to develop highly reliable and efficient technological units incorporating the performance of low technological operations in one device.
 Conclusions and practical significance. Based on the analysis of vibrating machines with a liquid environment, the results of research aimed at improving technologies and appropriate technical means to process bulk, lump and rod materials in air and liquid environments are provided. The solution of linear differential equations resulted in obtaining amplitude parameters of steady oscillations of an installation working body with relevance to the movement of working camera points and the installation angular oscillations as well. It has been proved that the amplitude of the vertical oscillations of the point is equal to the amplitude of the circular oscillations of the installation gravity center. Obtained rational trajectories of installation point oscillations to determine rational parameters are based on the requirements of material processing technology. The developed calculation methods can be used while studying machine dynamics of other types of a similar class containing liquid in the working space. Installation design makes it possible to adjust the oscillation amplitude and the nature of the trajectory of the installation working body points within wide limits.
 Keywords: rod or bulk material, motion kinematics, processing, vibrating machines, vibration trajectories, liquid, or air environment.

Quasi-Continuous Wave Pulsed Laser Welding of Copper Lap Joints Using Spatial Beam Oscillation.

Laser beam welding of copper (Cu) using near-infrared radiation is extremely challenging due to its high thermal conductivity and large laser reflectivity. In the present study, the challenges and benefits of using spatial beam oscillation during quasi-continuous wave (QCW) pulsed laser beam welding of 0.4 mm Cu to 1 mm Cu in lap joint configuration are presented. This work demonstrates how laser beam oscillating parameters can be used to control the laser weld quality and laser weld dimensions for Cu-Cu joining. Compared to a non-oscillated laser beam, welds made using laser beam oscillation showed fewer spatters, porosities, and better surface quality. Four levels of oscillating amplitudes (0.2 mm, 0.4 mm, 0.6 mm, and 0.8 mm) and oscillating frequencies (100 Hz, 200 Hz, 300 Hz, and 400 Hz) were compared to reveal the effect of beam oscillation parameters. The weld width was mainly controlled by oscillating amplitude, while weld penetration was affected by both oscillating amplitude and frequency. As the oscillating amplitude increased, the weld width increased while the weld penetration decreased. Increasing the oscillating frequency reduced the weld penetration but had a negligible effect on the weld width. The maximum tensile force of approximately 1944 N was achieved for the joint with a high width-to-depth ratio with an oscillating amplitude of 0.8 mm and an oscillating frequency of 200 Hz.

WIMP and FIMP dark matter in singlet-triplet fermionic model

We present an extension of the SM involving three triplet fermions, one triplet scalar and one singlet fermion, which can explain both neutrino masses and dark matter. One triplet of fermions and the singlet are odd under a Z2 symmetry, thus the model features two possible dark matter candidates. The two remaining Z2-even triplet fermions can reproduce the neutrino masses and oscillation parameters consistent with observations. We consider the case where the singlet has feeble couplings while the triplet is weakly interacting and investigate the different possibilities for reproducing the observed dark matter relic density. This includes production of the triplet WIMP from freeze-out and from decay of the singlet as well as freeze-in production of the singlet from decay of particles that belong to the thermal bath or are thermally decoupled. While freeze-in production is usually dominated by decay processes, we also show cases where the annihilation of bath particles give substantial contribution to the final relic density. This occurs when the new scalars are below the TeV scale, thus in the reach of the LHC. The next-to-lightest odd particle can be long-lived and can alter the successful BBN predictions for the abundance of light elements, these constraints are relevant in both the scenarios where the singlet or the triplet are the long-lived particle. In the case where the triplet is the DM, the model is subject to constraints from ongoing direct, indirect and collider experiments. When the singlet is the DM, the triplet which is the next-to-lightest odd particle can be long-lived and can be probed at the proposed MATHUSLA detector. Finally we also address the detection prospects of triplet fermions and scalars at the LHC.

Diffuse supernova neutrino background as a probe of late-time neutrino mass generation

The relic neutrinos from old supernova explosions are among the most ancient neutrino fluxes within experimental reach. Thus, the diffuse supernova neutrino background (DSNB) could teach us if neutrino masses were different in the past (redshifts $z\ensuremath{\lesssim}5$). Oscillations inside the supernova depend strongly on the neutrino mass-squared differences and the values of the mixing angles, rendering the DSNB energy spectrum sensitive to variations of these parameters. Considering a purely phenomenological parametrization of the neutrino masses as a function of redshift, we compute the expected local DSNB spectrum here on Earth. Given the current knowledge of neutrino oscillation parameters, especially the fact that $|{U}_{e3}{|}^{2}$ is small, we find that the ${\ensuremath{\nu}}_{e}$ spectrum could be significantly different from standard expectations if neutrinos were effectively massless at $z\ensuremath{\gtrsim}1$ as long as the neutrino mass ordering is normal. On the other hand, the ${\overline{\ensuremath{\nu}}}_{e}$ flux is not expected to be significantly impacted. Hence, a measurement of both the neutrino and antineutrino components of the DSNB should allow one to test the possibility of recent neutrino mass generation.

Uncertainties in neutrino oscillation parameter sensitivity due to resonance processes at NOνA

The long baseline (LBL) neutrino experiments use heavy nuclear targets for neutrino scattering in which nuclear effects give rise to complications in measuring the neutrino oscillation parameters up to high precision. These nuclear effects are not yet fully understood and therefore need to be quantified as they contribute to the systematic uncertainties. Precision reconstruction of neutrino energy is one of the main components in measuring the oscillation parameters, and it is required that the neutrino energy is reconstructed with very high precision. In this work, we investigate the effects of the resonance (RES) interaction process using two models for carbon target for [Formula: see text] disappearance channel of the NO[Formula: see text]A experiment, on neutrino-nucleus scattering cross-section, events, and neutrino oscillation parameter sensitivity. We also incorporate the realistic detector specifications of NO[Formula: see text]A. To quantify the systematic uncertainties due to RES interactions, we compare the cross-sections, events, and sensitivity analysis for two models of RES processes—Rein–Sehgal (RS) and Berger–Sehgal (BS), and comment on which model produces more precision. We observe that RES processes contribute significantly, and should be included carefully in models while extracting neutrino oscillation parameters.

Two-Zero Textures Based on A4 Symmetry and Unimodular Mixing Matrix

We propose a phenomenological model of two-zeros Majorana neutrino mass matrix based on the A4 symmetry, where the structure of mixing matrix is a unimodular second scheme of trimaximal TM2, and the charged lepton mass matrix is diagonal. We show that, among seven possible two-zero textures with A4 symmetry, only two textures, namely the texture with Mee=0 and Meμ=0 and its permutation, are acceptable in the non-perturbation method, since the results associated with these two textures are consistent with the experimental data. We obtain a unique relation between our phases, namely ρ+σ=ϕ±π, and an effective equation sin2θ13=23Rν where Rν=δm2Δm2. Then, only by using the experimental ranges of Rν, we obtain the allowable range of the unknown parameter ϕ as the phase of TM2 mixing matrix, which leads to obtaining not only the ranges of all neutrino oscillation parameters of the model (which agree well with experimental data) but also with the masses of neutrinos, the Dirac and Majorana phases and the Jarlskog parameter, and to predict the normal neutrino mass hierarchy. Finally, we show that all the predictions regarding our two specific textures agree with the corresponding data reported from neutrino oscillation, cosmic microwave background and neutrinoless double beta decay.

Beam oscillating parameters on pore inhibition, recrystallization and grain boundary characteristics of laser-arc hybrid welded AZ31 magnesium alloy

Oscillating laser-arc hybrid welding of AZ31B magnesium alloy was carried out, the effects of beam oscillation parameters on pore inhibition, microstructure, grain boundary characteristics and tensile properties were investigated. The results showed that the pore formation can be inhibited with oscillating frequency higher than 75 Hz and radius smaller than 0.5 mm. The columnar grains neighboring the fusion line can be broken by the beam oscillation behavior, while the grain growth was promoted with the increase of frequency or radius. It should be noted that the coincidence site lattice (CSL) boundaries were mainly Σ13b and Σ29 boundaries, which were contributed by {101¯2} tensile twins and {112¯2} compression twins, respectively. The total fraction of CSL boundaries reached maximum at radius of 0.25 mm and frequency of 75 Hz, which was also confirmed as the optimized parameters. In this case, the elongation rate increased up to 13.2%, 12.8% higher than that of the weld without beam oscillation. Finally, the pore formation and inhibition mechanisms were illustrated according to the state of melt flow and keyhole formation, the abnormal growth was discussed basing on secondary recrystallization, and the relationship among the pore formation, grain size, boundary characteristics and weld toughness were finally established.

Dispersion of fine settling particles in a tidal wetland flow

An investigation on transport of fine sediment particles in a tidal wetland flow is presented in the current research. The model of this work is based on an advection diffusion equation whose solution reveals the water phase based concentration of settling particles. Using the method of moments, a system of moment equations are derived from the governing equation. A finite difference implicit scheme is employed to solve the equations of moment. The behavior of Taylor effective dispersivity due to the variation of settling velocity of fine particles for oscillatory current with or without nonzero mean is predicted. The mean concentration distribution along the longitudinal direction is obtained using the Hermite polynomial and first four central moments. It is shown that for greater settling velocity, the dispersion procedure is inhibited. Some significant effects of vegetation factor, time period, oscillation parameter on environmental dispersivity, skewness and mean concentration profile are shown. The results of the present study are very important to understand the process of sedimentation and wastewater treatment in a tidal wetland flow.

Simulation study of tau neutrino events at the ICAL detector in INO

We present the first detailed simulation study of tau neutrino-induced charged current (CC) events from atmospheric neutrino interactions in the Iron Calorimeter (ICAL) detector at the proposed India-based Neutrino Observatory (INO) laboratory. Since the intrinsic atmospheric neutrino flux at few to 10s of GeV energy comprises only electron and muon neutrinos (and anti-neutrinos) with negligible tau neutrino component, any signature of atmospheric tau neutrinos is a signal for neutrino oscillations. We study the tau leptons produced through these CC interactions via their hadronic decay. These events appear as an excess over the neutral current (NC) background where hadrons are the only observable component. We find that the presence of tau neutrinos in the atmospheric neutrino flux can be demonstrated to nearly $4\sigma$ confidence with 10 years data; in addition, these events are sensitive to the neutrino oscillation parameters, $\sin^2\theta_{23}$ and $\vert \Delta m_{31}^2 \vert$ (or $\vert \Delta m_{32}^2 \vert$), in the 2--3 sector. Finally, we show that combining these events with the standard muon analysis which is the core goal of ICAL further improves the precision with which these parameters, especially the octant of $\theta_{23}$, can be measured.

Light as a quantum back-action nullifying meter

We propose a new, to the best of our knowledge, method to overcome quantum back-action in a measurement process using oscillators. An optical oscillator is used as a meter to measure the parameters of another open oscillator. The optical oscillator is synthesized such that the optical restoring force counters any perturbations induced by the quantum back-action phenomena. As a result, it is shown that the quantum back-action in continuous measurement is suppressed in the low frequency regime, i.e., for frequencies much smaller than the resonance frequency of the open oscillator. As the meter plays the role of measuring parameters as well as suppressing the quantum back-action, we call it a quantum back-action nullifying meter. As an application of this method, synthesis of the quantum back-action nullifying optical oscillator for suppressing radiation pressure force noise in linear and non-linear optomechanics is described.