We discuss Z-production in deep inelastic scattering \(e + p \rightarrow e + Z + X\) using the parton model, in the context of the Standard Model at leading order. In contrast to the deep inelastic ep-scattering (\(e + p \rightarrow e + X\)), where \(\tilde{Q}^{2}\), the momentum transfer square, is unambiguous, in the case of boson production it depends upon the mechanism involved, that is, it is

Using the same diffuser, linear, quadratic and Hamming apertures can form static speckle images. The distribution of the obtained speckle images using modulated apertures is computed by examining the full width at half maximum (FWHM) of the autocorrelation function of the sampled speckle pattern. The FWHM results are compared with the results obtained with open circular aperture. In addition, the effects

The heat transfer effects in rotating flow above an extensible surface immersed in a non-Newtonian fluid obeying Sisko fluid model is considered in this article. The model is widely accepted for analysing flow behaviour of many industrial liquids including lubricating greases. Thermal transport existing in the non-linear radiative heat flux is investigated. Conservation equations are simplified using

Design, fabrication, characterisation and calibration of a three-axis, ring-core, second harmonic fluxgate magnetometer is described in detail. Owing to the good material selection, precise structural fabrication, and high-performance processing unit, in addition to implementation of a novel and effective calibration algorithm, the sensor features good characteristics such as \(0.1^{\circ }\) non-orthogonality

By using the theory of group-invariant solutions, the symmetries of the motion equation of plane curve in \(SL'(2)\) geometry is presented. Group-invariant solutions associated with one-dimensional optimal system are obtained and classified.

In this article, analytical and numerical solutions to the simplified modified Camassa–Holm (MCH) equation by using the Riccati–Bernoulli (RB) sub-ODE method and moving mesh method are obtained. Some new solutions are given. The discrtisation of the presented model is introduced in the form of finite difference operators. Some 3D graphs for the presented solution are plotted with the aid of the Matlab

The coherent light interacting with a direct band-gap semiconductor is modelled as two coupled harmonic oscillators with Kerr-type nonlinearity in one of the oscillators. By considering the nonlinearity in the exciton mode, we derive approximate analytical solutions of the coupled differential equations involving two bosonic modes. For both photon and exciton modes which are in initial coherent states

A wide-band, compact size, long-range surface-tolerant ultrahigh frequency (UHF) radiofrequency identification (RFID) sensor is proposed for internet of things (IOT) applications. The proposed sensor is designed and fabricated on a rigid FR4 substrate. The equivalent circuit analysis is performed to validate the performance of the sensor. The RFID tag exhibits a wide bandwidth of 455 MHz, long reading

A study in nonlinear mechanical sciences on modelling has been carried out to analyse the combined effect of rotation and Darcy parameter with forced convective heat transfer on the steady flow of magnetic nanofluid over a rotating disk. The basic idea of the Neuringer–Rosensweig (NR) model has been used for the equations of motion and the governing nonlinear time-independent coupled partial differential

The bismuth-based non-toxic and lead-free alloys have been investigated for their advanced photon attenuation and photon energy absorption characteristics over wide \(\upgamma \)-ray energy regime from 1 keV to 20 MeV. For this study, we selected five bismuth containing alloys with composition: Bi50Sn\({(50-x)}\)Znx where \(x=0, 10, 20, 30, 40 \,\hbox {wt}.\%\). The mass attenuation coefficient values

Cluster decay of the superheavy nuclei \(^{270\text {--}318}118\) has been studied taking Coulomb and proximity potentials as interacting barriers. This study is based on the concept of cold valley. Cluster decay half-lives and other characteristics are computed for various clusters. The predicted \(\alpha \) decay half-life values are compared with other theoretical models and also with the sole experimental

The aim of this work is to provide energy level calculations among the lowest 71 levels arising out of \(1s^{2}\) and 1snl (\(n\le 6\), \(l\le (n-1)\)) configurations of He-like lithium. The calculations are carried out through the relativistic configuration interaction approach and the second-order many-body perturbation theory implemented in the flexible atomic code. We provide accurate calculations

Present paper studies the contribution of both the quantum effect and the dust size distribution effect on the shock wave characters. It is concluded that the quantum effect of dust particles is negligible, while the quantum effects of both electrons and ions on the shock wave of a quantum dusty plasma cannot be neglected in certain cases. It is found that the speed and the amplitude of the shock wave

The effects of different axisymmetric forebody shapes have been studied on the non-axisymmetric (helical) global modes of the boundary layer developed on a circular cylinder. Sharp cone, ellipsoid and paraboloid shapes have been considered with the fineness ratio (FR) of 2.5, 5.0 and 7.5. The base flow is in line with the cylinder’s axis at the inflow boundary, and hence the base flow is axisymmetric

We report a new microscopic equation of state (EoS) of pure neutron matter (PNM) at zero temperature using the recent realistic two-body interaction derived in the framework of chiral perturbation theory (ChPT). The EoS is derived using the Brueckner–Bethe–Goldstone quantum many-body theory in the Brueckner–Hartree–Fock approach. We have calculated the EoS of PNM at low and high densities using LO

This work provides an analytical investigation of the time-fractional Kundu–Eckhaus (KE) equation. We use the symmetry of the Lie group as an appropriate tool which deals with the wide class of fractional-order differential equations in Riemann–Liouville sense. In the current work, firstly, we employ classical Lie symmetries to obtain similarity reductions of nonlinear generalised time-fractional KE

The effect of nuclear magnetic dipole moment of hydrogen, deuterium and tritium isotopes on the electron atomic energy has been studied and analysed in this work. The electromagnetic Hamiltonian was rewritten in terms of the orbital angular momentum \(L_e\) of the electron, the gyromagnetic ratio \(\gamma _N\) of the nucleus and its total angular momentum \(J_N\). The first-order energy correction

An equivalent energy-dependent local potential corresponding to Coulomb plus Graz separable potential is constructed through simple rearrangement of the Schrödinger equation. It is conjectured that local Coulomb-like potential is equally applicable for the traditional phase function method. The merit of our constructed potential is thus judged by studying nucleon–nucleon and alpha–nucleon systems through

Breakup reactions at deep sub-barrier incident energies are the less investigated in the breakup of loosely-bound systems. Motivated by a recent study by Pakou et al (Phys. Rev. C 102:031601(R), 2020), we further analyse the breakup of \(^8{\mathrm{B}}\) nucleus on a lead target at deep sub-barrier incident energies. It is found that at these energies, continuum–continuum couplings enhance the breakup

We consider Kasner space–time describing anisotropic three-dimensional expansion of RHIC and LHC fireball and study the generalisation of Bjorken’s one-dimensional expansion by taking into account second-order relativistic viscous hydrodynamics. Using time-dependent AdS/CFT correspondence, we study the late-time behaviour of the Bjorken flow. From the conditions of conformal invariance and energy–momentum

In this paper, structural, electronic, thermal and thermoelectric properties of \(\hbox {Al}_{\mathrm {0.75}}\hbox {B}_{\mathrm {0.25}}\)As under 0, 2, 4 and 6 GPa pressure have been investigated based on density functional theory. Values of band gaps under 4 and 6 GPa pressure have been increased. The values of group velocity have been increased with increment in pressures from 0 GPa, too. The value

We study and present the results of curvature for different symmetry classes (BDI, AIII and A) of model Hamiltonians and also present the transformation of model Hamiltonian from one distinct symmetry class to the other based on the curvature property. We observe the mirror symmetric curvature for the Hamiltonian with BDI symmetry class but there is no evidence of such behaviour for Hamiltonians of

By exploiting higher partial wave solutions for the Hulthén potential, constructed via the factorisation method, closed form analytical expressions of the Fredholm determinants for motion in Hulthén plus modified Graz separable potential are constructed to study on-shell scattering up to partial wave \(\ell =2\). Phase shifts for different states of \(\alpha \)-\(^{{3}}\)H and \(\alpha \)-\(^{{3}}\)He

By employing the asymptotic iteration method (AIM), we solved the three-dimensional time-independent Schrödinger equation with the anharmonic Eckart potential model. The expression for the eigensolution of the anharmonic Eckart potential was obtained. With the help of the ro-vibrational energy spectra obtained, we derived the expressions for the ro-vibrational partition function and other thermodynamic

The study of defects or vacancies helps to understand the transport mechanism that occurs electrically and thermally in materials. It also deals with the mechanical properties of materials. In the present study, the extension of qualitative size-dependent model proposed by Jiang for cohesive energy of nanomaterials is done and size dependence of vacancy formation energy, vibrational frequency and vacancy

The main purpose of this paper is to investigate the complicated dynamical behaviours as well as the mechanism of a Filippov-type system. By introducing a non-smooth term and a periodic external excitation to a four-dimensional laser system, a new Filippov-type system with two scales can be obtained. When an order gap exists between the exciting frequency and the natural one, the whole excitation term

The structural, electronic, magnetic and thermodynamic properties of the half-Heusler alloy CoTcSn are determined using FP-LAPW method based on density functional theory (DFT). The exchange-correlation potential is treated with the generalised gradient approximation (GGA) described by Perdew–Burke–Ernzerhof (PBE-GGA), GGA plus band-correlated Hubbard parameter (GGA\(+U\)) and GGA\(+U\) plus Tran–Blaha-modified

By studying the time series of logistic maps, dark lines in bifurcation diagrams and cobweb diagrams, characteristics of sequential iterations of the map are found. Before the merging together two chaotic bands, sequential iterations of the map present an ordered state. After that, with the instability of the hyperstable periodic orbit, sequential iterations of the map appear disordered. Therefore

Emergence of different interesting and insightful phenomena in different length scales is the heart of quantum many-body system. We present emergence of quantum phases for the interacting helical liquid of topological quantum matter. We also observe that Luttinger liquid parameter plays a significant role to determine different quantum phases. We use three sets of renormalisation group (RG) equations

We simulate triaxial deformation of a single crystal iron at \(10^6\ \hbox {s}^{-1}\) strain rate to investigate the void evolution dynamics in a single crystal iron. We find that the peak tensile pressure is very close to the spall strength of the single crystal iron. As strain rate decreases, the peak tensile pressure approaches the void nucleation threshold of the single crystal iron. The damage

In the present study, zero field splitting (ZFS) parameters are investigated for Mn(II) ion doped perovskites, viz. \(\hbox {PbTiO}_{3},\hbox {BaTiO}_{3}\) and \(\hbox {SrTiO}_{3}\). The ZFS parameter and magnetisation induced in the host are investigated using quantum mechanical perturbation theory and classical statistics. A mathematical derivation is proposed to study magnetisation and ZFS due to

We study the symmetry and integrability of a modified Camassa–Holm equation (MCH), with an arbitrary parameter k, of the form $$\begin{aligned} u_{t}+k(u-u_{xx})^2u_{x}-u_{xxt}+(u^{2}-{u_{x}}^2)(u_{x}-u_{xxx})=0. \end{aligned}$$ The commutator table and adjoint representation of the symmetries are presented to construct one-dimensional optimal system. By using the one-dimensional optimal system, we

The emergent Universe scenario is obtained in flat Universe with equation of state (EoS) (\(P =B\rho -A\rho ^{{1}/{2}}\)) (where A and B are constants) as per Mukherjee et al. The EoS of this emergent Universe (EU) model can describe the current accelerated expansion and the initial singularity of the Universe. Following the standard thermodynamical criteria, stability of the EU models has been discussed

In this paper, we report the existence of bursting oscillations in systems governed by a second-order differential equation with only one signum nonlinearity term and time-delay feedback, driven by the slowly varying external force. Depending on the sign of the strength of signum nonlinearity, two cases are studied: two-well and single-well potentials. The external force acts as the control parameter

The unsteady flow of the ferrofluid between two rotating and contracting disks has been investigated in the presence of a uniform magnetic field. A similarity transformation is used to convert the governing partial differential equations into a set of nonlinear ordinary differential equations. The transformed system is then solved numerically through mathematical modelling in COMSOL Multiphysics in

Employing the dielectric tensor elements and taking into account the time variations of a rotating magnetic field (RMF) leading to the electric field generation responsible for particle acceleration, we develop a closed mathematical form for the radiated power absorbed by a long column containing multilayer inhomogeneous drift plasma with elliptical cross-section. To this end, cold-fluid equations

We find new stellar models to the field equations for charged anisotropic spheres. We use linear quark equation of state for strange quark matter. We choose a new form of pressure anisotropy as a rational function. In our model, we regain previous isotropic and anisotropic stellar models as specific cases. Isotropic models regained are those found by Komathiraj and Maharaj, Mak and Harko, and Misner

We model and investigate the dynamics and modulation performance of semiconductor laser integrated with two short external cavities facing the front and back facets with the aim to enhance the modulation bandwidth of the laser for use in high-speed photonics. The coupled cavities provide double optical feedback (DOFB) to the laser cavity through the partially reflecting facets of the laser cavity.

Al-doped ZnO (AZO) thin films have been deposited onto the glass substrate via sol–gel spin coating method with different Al concentrations (0, 2, 4, 6, 8, 10 at.%). The growth orientation and crystalline structure were investigated by studying the X-ray diffraction (XRD) pattern. The XRD results reveal that the thin films show wurtzite phase with preferential orientation along the c-axis (002) plane

Under the classical (strong) pump condition, the Hamiltonian involving the signal and the idler modes of a non-degenerate parametric oscillator is exhibited. Without using the usual rotating wave approximation (RWA), the analytical solutions of the field operators are used to investigate the antibunching of photons of the input radiation field coupled to the non-degenerate parametric oscillator. By

Two-dimensional transition metal chalcogenides like GeSe, GeS and SnSe are widely used in a variety of electrical and optoelectrical applications. Alloying becomes the most important tool to alter the structural, optical and electrical properties of the material. Here, efforts have been applied to grow the crystals of GeS\(_{x}\)Se\(_{1-x}\) \((x = 0,0.5,1)\) using iodine (I\(_{2})\) as a transporting

Rare earth (RE)-based \(\hbox {MgCu}_2\)-type intermetallic compounds are studied by first-principles calculations to search their spintronic applications and thermodynamic stability. We found in our observations that both \(\hbox {EuPt}_2\) and \(\hbox {GdPt}_2\) have half-metallic properties. The band gap arises in spin-down channel which is found to be enhanced when we move from \(\hbox {EuPt}_2\)

In this paper, the problem of exponential synchronisation between time-delay spatiotemporal network and target system is studied. Based on the Lyapunov stability principle, the Lyapunov–Krasovskii generic function with exponential form is designed, and the form of the synchronisation controller is determined, so that the exponential synchronisation is realised between the time-delay spatiotemporal

In this article, a novel shifted Gegenbauer operational matrix (SGOM) of fractional derivative in the Caputo sense is derived. Based on this operational matrix, an accurate and effective numerical algorithm is proposed. The SGOM of fractional derivative in conjunction with the tau method are used for solving the constant and variable coefficients space–time fractional telegraph equations (FTE) with

In this paper we have made use of reductive perturbation technique (RPT) and carried out homotopy analysis method (HAM) to investigate the effect of exchange correlation and quantum diffraction on the electrostatic waves in quantum magnetoplasma. We have derived a nonlinear Schrödinger equation (NLSE) by using RPT that describes the spatiotemporal evolution of an initial waveform. Apart from this technique

This article is concerned with the influences of the pressure work and Hall currents on the motion of a non-Newtonian nanofluid with heat and mass transfer inside a vertical symmetric channel. The fluid conforms to the Bingham–Papanastasiou model. The walls of the channel are assumed to be flexible, movable and sinusoidal. Thermal radiation, heat generation/absorption and chemical reaction are thus

Noise improves the reliability of logic operations if noise parameter is in certain proper region (reliable region), which is known as logical stochastic resonance (LSR). LSR attracts much attention due to its potential application in new-style logic devices. However, nothing is reported about the effect of cross-correlated sine-Wiener (CCSW) bounded noises on the reliability and agility of logic operations

Spintronic heterostructures are considered to be the new generation terahertz (THz) sources because of their capability of producing high power and broadband THz radiation. Here, we provide a brief review on the state-of-the-art in this field. The optically excited bi- and tri-layer combinations of ferromagnetic and non-magnetic thin films have become increasingly popular. Towards optimising the THz

The rheology of Burgers nanofluid flow over a stretching cylinder with convective transport of thermal and solutal energy is studied in the present article. The relaxation and retardation properties of viscoelastic fluid are examined for flow field and energy distribution. Moreover, the thermophoretic and Brownian forces are also incorporated in the phenomena of thermal and solutal energy distribution

The characteristics of ion-acoustic solitary waves in rotating, weakly relativistic, magnetised and collisionless plasma system comprising electron, positron and ion (EPI) under a periodic external force, whose constituents electron and positron obey Boltzmann distribution, are investigated by deriving forced Zakharov–Kuznetsov (FZK) equation. FZK equation is constructed using reductive perturbation

Due to the fluctuation of membrane potential of neuron, there are complex time-varying electromagnetic fields in nervous systems, and the exciting electromagnetic field will further regulate the discharge activities of neurons. In this paper, the coupling of magnetic flux variables to the membrane potential is realised by using a magnetron memristor, and then a 5D extended Hindmarsh–Rose (e-HR) neuron

In the present work, electro-optical and electronic properties of 4-n-pentyl-\(4^{\prime }\)-cyanobiphenyl (5CB) and \(4^{\prime }\)-cyano-4-n-pentyl-p-terphenyl (5CT) liquid crystal molecules have been investigated. The 5CB compound transforms from crystal to nematic phase at 24\(^\circ \)C and nematic to isotropic phase at 35.3\(^\circ \)C while 5CT compound transforms from crystal to nematic phase

The polycrystalline samples of gadolinium (Gd)-modified lead-zirconate-titanate (\(\hbox {Pb}_{\mathrm {1-}{x}}\hbox {Gd}_{x}\) (\(\hbox {Zr}_{\mathrm {0.52}}\hbox {Ti}_{\mathrm {0.48}})_{\mathrm {1-}{x}\mathrm{/4}} \hbox {O}_{\mathrm {3}})\) (\(x = 0, 0.07, 0.10\) and 0.12) (PGZT) ceramics near morphotropic phase boundary (MPB) were prepared by high-temperature solid-state reaction route. Electrical

In this work, we have performed the chemical functionalisation of metallic graphene nanoribbons (GNRs) with different functional groups. The analysis of graphene in terms of relative stability and electronic properties has been done. The HOMO–LUMO gaps are quantitatively analysed to reveal the influence of different functional groups including hydroxyl, carboxyl and hydrogen sulphide groups. Interestingly

Entropy generation analysis in steady two-dimensional, viscous, incompressible forced convective Falkner–Skan flow of Maxwell nanofluid over a static wedge embedded in a porous medium with temperature-dependent viscosity is examined. The Buongiorno’s model has been utilised, to get the flow governing higher-order coupled nonlinear partial differential equations (PDEs) from mass, momentum, energy and

A single diode laser and an electro-optic modulator (EOM)-operated magneto-optical trap (MOT) has been developed for a compact atomic fountain. For generating the required cooling and re-pumping laser beams for the MOT, an EOM operating at 6.58 GHz has been used to modulate the input laser beam. In the trapped cold atom cloud, the population in the two ground hyperfine states (\(F=1\) and \(F=2\))

A new terahertz (THz) temperature sensor, which is based on surface plasmon resonance (SPR) by prism coupling excitation at THz frequency, is proposed. A novel prism coupling structure is designed for the temperature sensor by using unique features of thermo-optic effect for silicon at 1 THz and the high THz emission effiency of InSb. The medium thickness for the THz temperature sensor structure is

In an ion beam plasma system, the effect of magnetically quantised degenerate trapped electron and positron, on small-amplitude ion-acoustic solitary waves are studied with the help of Korteweg–de Vries (KdV) equation. Here the magnetised positive ions and beam ions are considered as non-degenerate. The effect of magnetic quantisation, degenerate temperature, normalised positron concentration, normalised

Cosmic ray muon flux is measured by the coincidence technique using plastic scintillation detectors in the High Energy Physics Detector Laboratory at Bose Institute, Kolkata. Due to the COVID-19 outbreak and nationwide complete lockdown, the laboratory was closed from the end of March 2020 till the end of May 2020. After lockdown, although the city is not in its normal state, we still were able to

The versatile and exactly solvable Scarf II potential has been predicting, confirming and demonstrating interesting phenomena in complex PT-symmetric sector, most impressively. However, for the non-PT-symmetric sector, it has gone underutilised. Here, we present the most simple analytic forms for the scattering coefficients \((T(k),R(k),|\det S(k)|)\). On the one hand, these forms demonstrate earlier