Study of the matter density distributions of halo nuclei 6He and 16C using the binary cluster model

The harmonic oscillator (HO) and Gaussian (GS) wave functions within the binary cluster model (BCM) have been employ to investigate the ground state neutron, proton and matter densities as well as the elastic form factors of two-neutron 6He and 16C halo nuclei. The long tail is a property that is clearly revealed in the density of the neutrons since it is found in halo orbits. The existence of a long tail in the neutron density distributions of 6He and 16C indicating that these nuclei have a neutron halo structure. Moreover, the matter rms radii and the reaction cross section (σr) of these nuclei have been calculated using the Glauber model.

Dispersion relation analysis of the radiative corrections to gA in the neutron β-decay

We present the first and complete dispersion relation analysis of the inner radiative corrections to the axial coupling constant gA in the neutron β-decay. Using experimental inputs from the elastic form factors and the spin-dependent structure function g1, we determine the contribution from the γW-box diagram to a precision better than 10−4. Our calculation indicates that the inner radiative corrections to the Fermi and the Gamow-Teller matrix element in the neutron β-decay are almost identical, i.e. the ratio λ = gA/gV is almost unrenormalized. With this result, we predict the bare axial coupling constant to be $$ {\overset{\circ }{g}}_A=-1.2754{(13)}_{\mathrm{exp}}{(2)}_{\mathrm{RC}} $$ g ∘ A = − 1.2754 13 exp 2 RC based on the PDG average λ = −1.2756(13).

Study of the Density Distributions and Elastic form Factors of the Exotic Nuclei, 8He And 26F, Via the Three-Body Model

The matter, proton, and neutron density distributions of the ground state, the nuclear root-mean-square (rms) radii, and the elastic form factors of a two- neutron, 8He and 26F, halo nuclei have been studied by the three body model of within the harmonic oscillator (HO) and Woods-Saxon (WS) radial wave functions. The calculated results show that the two body model within the HO and WS radial wave functions succeeds in reproducing the neutron halo in these exotic nuclei. Moreover, the Glauber model at high energy (above several hundred MeV) has been used to calculate the rms radii and reaction cross sections of these nuclei.

Low-Energy Quark Mass Test for U and D Via Elastic Form Factors

The study was aimed at providing a device to estimate the range of values of the u- and d-quark masses through the elastic ep-scattering form factors at the low energy regime. ROOT generated dcsep data sets, from theoretical and experimental form factors, were compared to modified dcseq and their intersections were determined from the average of a total of 3000 events for each dcs at various scattering angles selected randomly from 0o to 180o. The proton mass was required as a parameter used in the relativistic recoil factor of dcseq to shift its distribution closer to dcsep thereby attaining the critical intersections. For quarks carrying effective masses, the extrapolated energy intersection of dcsep generated from the average of all form factors with the modified dcseu is 226.00013MeV2 and this is lesser than that of the modified dcsed at 1093.00004MeV2 with bin size of 1MeV2 and their respective dcs intersections are 10.07049x10-4 and 0.36976x10-4, in barns. Summary of results are also given for quark masses derived from MS scheme and Lattice QCD. By considering all possible scattering angles at fixed transfer momentum, the relativistic recoil factor was treated as a constant that shifted the distribution and gave rise to a tool in estimating quark mass range.

Study of the proton halo structure of nuclei 23Al and 27P using the binary cluster model

The neutron, proton, and matter densities of the ground state of the proton-rich 23Al and 27P exotic nuclei were analyzed using the binary cluster model (BCM). Two density parameterizations were used in BCM calculations namely; Gaussian (GS) and harmonic oscillator (HO) parameterizations. According to the calculated results, it found that the BCM gives a good description of the nuclear structure for above proton-rich exotic nuclei. The elastic form factors of the unstable 23Al and 27P exotic nuclei and those of their stable isotopes 27Al and 31P are studied by the plane-wave Born approximation. The main difference between the elastic form factors of unstable nuclei and their stable isotopes is caused by the variation in the proton density distributions, especially the details of the outer part. Moreover, the Glauber model is used to calculate the matter rms radii and reaction cross-section of these exotic nuclei. The calculated results of the mentioned nuclei give a good accordance with the experimental data.

Hybrid nature of the abnormal solutions of the Bethe–Salpeter equation in the Wick–Cutkosky model

In the Wick–Cutkosky model, where two scalar massive constituents interact by means of the exchange of a scalar massless particle, the Bethe–Salpeter equation has solutions of two types, called “normal” and “abnormal”. In the non-relativistic limit, the normal solutions correspond to the usual Coulomb spectrum, whereas the abnormal ones do not have non-relativistic counterparts – they are absent in the Schrödinger equation framework. We have studied, in the formalism of the light-front dynamics, the Fock-space content of the abnormal solutions. It turns out that, in contrast to the normal ones, the abnormal states are dominated by the massless exchange particles (by 90 % or more), what provides a natural explanation of their decoupling from the two-body Schrödinger equation. Assuming that one of the massive constituents is charged, we have calculated the electromagnetic elastic form factors of the normal and abnormal states, as well as the transition form factors. The results on form factors confirm the many-body nature of the abnormal states, as found from the Fock-space analysis. The abnormal solutions have thus properties similar to those of hybrid states, made here essentially of two massive constituents and several or many massless exchange particles. They could also be interpreted as the Abelian scalar analogs of the QCD hybrid states. The question of the validity of the ladder approximation of the model is also examined.

Study of the Exotic Structure of Neutron-Rich 14B and 17C Nuclei Using the Binary Cluster Model

The neutron, proton, and matter densities of the ground state of the 14B and 17C exotic nuclei are analyzed using the binary cluster model (BCM). Two density parameterizations are used in BCM calculations namely; Gaussian (GS) and harmonic oscillator (HO) parameterizations. According to the calculated results it found that, the BCM gives a good description of the nuclear structure for above neutron-rich exotic nuclei. The elastic form factors of theunstable 14B and 17C exotic nuclei and those of their stable isotopes 10B and 13C are determined using the plane-wave Born approximation. The main difference between the elastic form factors of unstable nuclei and their stable isotopes is due to the difference in the center of mass correction. Moreover, the Glauber model is used to calculate the matter rms radii and reaction cross section of these exotic nuclei. The calculate results of the mentioned nuclei give a good accordance with the experimental data.

Electronic Skins for Healthcare Monitoring and Smart Prostheses

The human skin is a unique organ that embeds multiple functions that no artificial systems can currently replicate. Advances in materials science and engineering are driving the design of electronic skins—large-area sensor arrays that mimic some sensory modalities and have the soft, elastic form of natural skin. Here, we focus on electronic skins designed to be worn on the human body for healthcare monitoring or prosthetic applications. The primary sensing modalities are mechanical, thermal, and electrophysiological. We review key materials and associated designs needed to manufacture electronic devices that can conform to the human body and move along with it. Electronic skins offer exciting opportunities for human–machine interfaces. Expected final online publication date for the Annual Review of Control, Robotics, and Autonomous Systems, Volume 4 is May 3, 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Electron Scattering from Some Fp- Shell Nuclei with Inclusion the Effect of Short-Range Correlation

The effects of short-range correlation on elastic Coulomb (charge) form factors, charge density distributions as well as root mean square charge radii of various nuclei (for instance, 46, 48, 50Ti, 52, 54Cr, 56, 58Fe, and 72, 74, 76Ge nuclei) are examined. The one- and two body terms of the cluster expansion together with the single-particle harmonic oscillator wave functions are utilized. For the purpose of embedding these effects into the formulae of charge density and form factor we employ the correlation function of Jastrow-type. These formulae depend upon the short-range correlation parameter (which instigates from the Jastrow function) and the oscillator size parameter Both and are found by the fitting to the measured elastic form factors. It is noticed that the embedding of short-range correlation effects into the calculations of and is a requisite for the achievement of a vital change in the computed results and remarkably vital for the characterization of the measured data.