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The four-body distorted-wave approximation (DW-4B) is used to investigate the electron removal from water molecules by the impact of hydrogen-like projectiles. The incident energy is considered in a range of 20 to 2000 keV/amu. Our goal is to establish the relative importance of the intermediate ionization continua of the active electron and the electron–electron correlations. The calculations are based on the independent electron model. The description of initial ground state molecular orbitals of water are described by a complete-neglect-of-differential-overlap method based on the linear combination of atomic orbitals. Numerical results for the total cross sections are compared with other results and found to be in good agreement with the available experimental findings. Differentiation between the reactions of single-electron ionization and single-electron capture in electron removal process as a function of impact energies is also analyzed. Finally, the dependence of cross sections regarding electron removal on different descriptions of molecular orbitals as well as the simplest additivity rule are discussed. • Four body distorted-wave model is used to study the electron removal process. • Theoretical cross sections data about the ionization and capture are needed in fundamental studies of charged particle interaction in biological matter. • Dressed projectile effects the cross sections of electron ionization and electron capture. [Display omitted] [ABSTRACT FROM AUTHOR]

The nature of equation of state for the neutron star matter is crucially governed by the density dependence of the nuclear symmetry energy. We attempt to probe the behaviour of the nuclear symmetry energy around the saturation density by exploiting the empirical values for volume and surface symmetry energy coefficients extracted from the precise data on the nuclear masses. [ABSTRACT FROM AUTHOR]

Empirically determined values of the nuclear volume and surface symmetry energy coefficients from nuclear masses are expressed in terms of density distributions of nucléons in heavy nuclei in the local density approximation. This is then used to extract the value of the symmetry energy slope parameter L. The density distributions in both spherical and well deformed nuclei calculated within microscopic framework with different energy density functionals give L = 59.0 ± 13.0 MeV. Application of the method also helps in a precision determination of the neutron skin thickness of nuclei that are difficult to measure accurately. [ABSTRACT FROM AUTHOR]

The density dependence of nuclear symmetry energy remains poorly constrained. Starting from precise empirical values of the nuclear volume and surface symmetry energy coefficients and the nuclear saturation density, we show how in the ambit of microscopic calculations with different energy density functionals, the value of the symmetry energy slope parameter L along with that for neutron skin can be put in tighter bounds. The value of L is found to be L = 64 ± 5 MeV. For 208Pb, the neutron skin thickness comes out to be 0.188 ± 0.014 fm. Knowing L, the method can be applied to predict neutron skin thicknesses of other nuclei. [ABSTRACT FROM AUTHOR]

Aims: Recent foodborne disease outbreaks have caused farmers to re‐evaluate their practices. In particular, concern that soil amendments could introduce foodborne pathogens onto farms and promote their survival in soils has led farmers to reduce or eliminate the application of animal‐based composts. However, organic amendments (such as composts and cover crops) could bolster food safety by increasing soil microbial diversity and activity, which can act as competitors or antagonists and reduce pathogen survival. Methods and Results: Leveraging a study of a 27‐year experiment comparing organic and conventional soil management, we evaluate the impacts of composted poultry litter and cover crops on soil chemistry, bacterial communities and survival of Salmonella enterica and Listeria monocytogenes. We found that bacterial community composition strongly affected pathogen survival in soils. Specifically, organic soils managed with cover crops and composts hosted more macronutrients and bacterial communities that were better able to suppress Salmonella and Listeria. For example, after incubating soils for 10 days at 20°C, soils without composts retained fourfold to fivefold more Salmonella compared to compost‐amended soils. However, treatment effects dissipated as bacterial communities converged over the growing season. Conclusions: Our results suggest that composts and cover crops may be used to build healthy soils without increasing foodborne pathogen survival. Significance and Impact of the Study: Our work suggests that animal‐based composts do not promote pathogen survival and may even promote bacterial communities that suppress pathogens. Critically, proper composting techniques are known to reduce pathogen populations in biological soil amendments of animal origin, which can reduce the risks of introducing pathogens to farm fields in soil amendments. Thus, animal‐based composts and cover crops may be a safe alternative to conventional fertilizers, both because of the known benefits of composts for soil health and because it may be possible to apply amendments in such a way that food‐safety risks are mitigated rather than exacerbated. [ABSTRACT FROM AUTHOR]

The nuclear matter parameters define the nuclear equation of state (EoS), they appear as coefficients of expansion around the saturation density of symmetric and asymmetric nuclear matter. We review their correlations with several properties of finite nuclei and of neutron stars within mean-field frameworks. The lower order nuclear matter parameters such as the binding energy per nucleon, incompressibility and the symmetry energy coefficients are found to be constrained in narrow limits through their strong ties with selective properties of finite nuclei. From the correlations of nuclear matter parameters with neutron star observables, we further review how precision knowledge of the radii and tidal deformability of neutron stars in the mass range 1 - 2 M ⊙ may help cast them in narrower bounds. The higher order parameters such as the density slope and the curvature of the symmetry energy or the skewness of the symmetric nuclear matter EoS are, however, plagued with larger uncertainty. From inter-correlation of these higher order nuclear matter parameters with lower order ones, we explore how they can be brought to more harmonious bounds. [ABSTRACT FROM AUTHOR]

Motivated by the interrelationships found between the various symmetry energy elements of the energy density functionals (EDF) based on the Skyrme forces, possible correlations among them are explored. A total of 237 Skyrme EDFs are used for this purpose. As some of these EDFs yield values of a few nuclear observables far off from the present acceptable range, studies are done also with a subset of 162 EDFs that comply with a conservative set of constraints on the values of nuclear matter incompressibility coefficient, effective mass of the nucleon and the isovector splitting of effective nucleon masses to see the enhancement of the correlation strength, if any. The curvature parameter K sym 0 and the skewness parameter Q sym 0 of the symmetry energy are found to be very well correlated with the linear combination of the symmetry energy coefficient and its density derivative L 0 . The isovector splitting of the effective nucleon mass, however, displays a somewhat meaningful correlation with a linear combination of the symmetry energy, its slope and its curvature parameter. [ABSTRACT FROM AUTHOR]

From empirically determined values of some of the characteristic constants associated with homogeneous nuclear matter at saturation and subsaturation densities, within the framework of a Skyrme-inspired energy density functional, we construct an equation of state (EoS) of nuclear matter. This EoS is then used to predict values of density slope parameters of symmetry energy L(ρ), isoscalar incompressibility K(ρ), and a few related quantities. The close consonance of our predicted values with the currently available ones for the density dependence of symmetry energy and incompressibility gleaned from diverse approaches offers the possibility that our method may help in settling their values in tighter bounds. Extrapolation of our EoS at supranormal densities shows that it is in good harmony with the one extracted from experimental data. [ABSTRACT FROM AUTHOR]

The thermal evolution of a few thermodynamic properties of the nuclear surface like its thermodynamic potential energy, entropy, and the symmetry free energy are examined for both semi-infinite nuclear matter and finite nuclei. The Thomas-Fermi model is employed. Three Skyrme interactions, namely, SkM*, SLy4, and SK255, are used for the calculations to gauge the dependence of the nuclear surface properties on the energy density functionals. For finite nuclei, the surface observables are computed from a global liquid-drop-inspired fit of the energies and free energies of a host of nuclei covering the entire periodic table. The hot nuclear system is modeled in a subtracted Thomas-Fermi framework. Compared to semi-infinite nuclear matter, substantial changes in the surface symmetry energy of finite nuclei are indicated; surface thermodynamic potential energies for the two systems are, however, not too different. Analytic expressions to fit the temperature and asymmetry dependence of the surface thermodynamic potential of semi-infinite nuclear matter and the temperature dependence of the surface free energy of finite nuclei are given. [ABSTRACT FROM AUTHOR]