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This work is devoted to study the structural and reactional properties of the prototypical example of the core–halo ( 9 Li– 11 Li) nuclei. The halo nucleus 11 Li consists of a central core of 9 Li surrounded by 2n–halo with very low separation energy ε 2 n = 378±5 KeV, reflecting the huge calculated root mean square radius value 4.11 fm. The elastic scattering potential at low and intermediate incident energies was a puzzle for decades of research on nuclear reactions. Single– and double–folding potentials describing the elastic scattering of 11 Li from the proton and 12 C, based on different effective interactions were constructed. Systematic comparison between the considered methods in terms of the renormalization coefficients is done. Based on the considered methods, the obtained potentials doesn’t need any renormalization in case of using real folding potential together with phenomenological imaginary potential and merely need renormalization almost approach unity in case of using complex folding potential to fit the total reaction cross sections and angular distributions along the measured data. Furthermore, correlations between real volume integrals and nucleon incident energies for the neutron drip–line 11 Li nucleus were proven along the whole scale of energies. [ABSTRACT FROM AUTHOR]

We employ the single folding model to calculate the optical potential (OP) for the p + 16 O scattering system, in which the exchange term of the OP is nonlocal. In most studies, this term is approximated to a local form to simplify the calculations. In this work, the folding OP, including the nonlocal exchange term, is constructed based on the CDM3Y3 effective nucleon-nucleon (NN) interaction. The Schrödinger equation for the nucleon-nucleus scattering with the nonlocal OP is solved exactly using the Lagrange-mesh R-matrix method. By comparing the scattering cross sections calculated with the nonlocal potential and the localized approximation, we can assess the impact of the nonlocality effects in proton-nucleus elastic scattering. The calculated results demonstrate that the nonlocality effect of the OP significantly influences the low-energy elastic scattering cross sections of p + 16 O. [ABSTRACT FROM AUTHOR]

By mapping the scalar Helmholtz equation (SHE) to the Schrödinger form we investigate the behavior of optical structure when the refractive index distribution n admits variation in the longitudinal direction only. Interpreting the Schrödinger equation in terms of a superpotential we determine the supersymmetric partners for n. We also obtain new analytical solutions for the refractive index profiles and provide graphical illustrations for them. [ABSTRACT FROM AUTHOR]

A nonlocal velocity-dependent optical potential was used to study the angular distribution of the differential cross section of nucleon–nucleus elastic scattering. The potential parameters were calculated by fitting elastic angular distributions over a wide range of energy (10-65 MeV) and mass (12-208). The real part of the local optical potential was calculated using the CDM3Y6-Paris interaction, whereas the imaginary part was a Woods-Saxon form factor and its derivative.

In order to model the spectroscopic and scattering properties of a quantum system, we propose and explore a new absorbing complex-type optical potential based on a combination of cosine functions. This function provides a high degree of smoothness to joint with a physical real-type potential. The capabilities of this function are investigated in terms of its effect on otherwise freely evolving quantum dynamics. We use our open-source programs to implement the Fourier Grid method with the Optimizer package (in Matlab), freely available at https://sourceforge.net/projects/optimizer-sovkov/. [ABSTRACT FROM AUTHOR]

Analysis of the latest high–precision cross sections of (α,γ) and (α,n) reactions on 144Sm below the Coulomb barrier is carried out using a consistent parameter set of the statistical model. This prevents the need to use empirical rescaling factors of either γ or neutron widths. Particular attention is paid to uncertainties of the calculated cross sections which are related to the accuracy of the primary data that were used to set up the consistent input parameters. The calculated cross sections are found in good agreement with the new experimental data for the 144Sm(α,n)147Gd reaction; however, the same is not true for the excitation function of 144Sm(α,γ)148Gd which decreases faster at incident energies below ∼12 MeV. An increase of the α-particle direct collective inelastic scattering at lower energies is found responsible for this decrease of the (α,γ) reaction cross sections. The consequent lower nuclear effects may correspond to the Coulomb excitation effect assumed, although in a different manner, within the so-called “α-potential mystery” for the same optical–potential account of α-particle absorption and emission as well.

A microscopic approach was used to analyze the elastic scattering of protons on 1 0 , 1 1 Be at incident energies of 9.1, 15.1, 39.1, and 59.3 MeV/nucleon for 1 0 Be and 1 1 Be (38.4 MeV/nucleon and 49.3 MeV/nucleon) within the framework of single folding (SF) and São-Paulo (SP) potentials. Also, the energy dependence of the reaction cross-sections of the considered reactions is investigated. The study was performed using FRESCO code on the free parameters ( N r , N I , N S , W s , W v , r I and a I ). The DFPOT code was used to compute the SF and SP potentials microscopically for the real and imaginary parts of the optical potential (OP), respectively. The OP was derived using two different nuclear density distributions since 1 1 Be as Gaussian–Gaussian (GG) ρ GG and Gaussian–Oscillator (GO) ρ GO , and the effective N–N interactions were represented in the Gaussian form. The resulting differential cross-sections agreed well with the given experimental data. [ABSTRACT FROM AUTHOR]

Experimental 7 Li + 27 Al elastic scattering angular distributions in the 6–89 MeV laboratory energy range have been re-analysed using different phenomenological and microscopic potentials to investigate the cluster nature of the weakly-bound 7 Li projectile and the associated break-up effect on the elastic scattering data. The consistency of the results obtained within the various implemented potentials was also analysed. A new microscopic dynamical polarisation potential was applied to simulate the significant coupling effect to the break-up channel, which is responsible for the observed reduction in the strength of the implemented real potentials. A reasonable agreement between the considered experimental results and the present theoretical calculations was obtained. The study confirms the absence of the usual threshold anomaly present in nuclear systems involving tightly-bound projectiles. [ABSTRACT FROM AUTHOR]

This article incorporates details of our calculations of the observable quantities for the scattering of electrons and positrons from a post transition metal Thallium (Tl), in the energy range of 1 eV ≤ E i ≤ 1 MeV, using the relativistic Dirac partial wave (phase-shift) analysis employing a complex optical-potential. Absolute differential, integrated elastic and inelastic, transport, total ionization, and total cross sections and a thorough study of the critical minima in the elastic differential cross sections along with the associated angular positions of the maximum polarization points in the Sherman function are provided to study the collision dynamics. The optical potential model incorporates the interactions of the incident electron and/or positron with both the nucleus and the bound electrons of the target atom. In-depth analyses of the spin asymmetry, which are sensitive to phases related interference effect, brought on by the various ingredients of the lepton-atom interaction, are also presented. The performance of the current approach to explain the observations, with the exception of the extremely low energy domain, is shown by a comparison of the previous experimental and theoretical results on this target atom. [ABSTRACT FROM AUTHOR]

Angular distribution of the differential cross section of α 40Ca elastic scattering has been investigated in the anomalous large angle scattering (ALAS) region by a nonlocal velocity dependent optical potential with surface term. The geometrical potential parameters were fixed and the depths of the potential were determined by fitting elastic angular distribution over the energy range (23–53.9 MeV). The real and the imaginary parts of the optical potential used here are of Woods–Saxon form factors. An energy dependence of the potential depths has been investigated at fixed geometrical potential parameters.

A concurrent assessment of all measured excitation functions for various reactions induced by neutrons on 93Nb, in addition to the results of TENDL-2021 and default parameters in TALYS-1.96, is given in this work. We use consistent parameter sets that were formerly obtained or validated by the analysis of other independent data, while no empirical rescaling factors of γ and/or neutron widths have been used. The correlation between the measured error bars of the primary data providing the consistent input parameters and the final uncertainty bands of the calculated results have been pointed out. At the same time, a proper account in this work of all available data for competitive reaction channels prevented compensation effects of less accurate model parameters. Remaining questions and the need for additional measurements are emphasized.

Experimental data on elastic and inelastic scattering of 50.5 MeV α-particles and 60 MeV 3He ions by 28Si nuclei were analyzed within the framework of the standard optical model of the nucleus, in which the effect of inelastic channels is taken into account by the phenomenological introduction of an imaginary absorbing part into the interaction potential between colliding nuclei. The optimal values of the internuclear interaction potential obtained as a result of the theoretical analysis were used to study the cross sections for inelastic scattering of helium ions with the excitation of the 1.78 and 4.61 MeV states of the nucleus under study. From the analysis by the channel coupling method, where the calculation was performed taking into account both elastic and inelastic channels, the value of the quadrupole deformation parameter for α-particles β2 = 0.37 and for 3He ions β2 = 0.49 was determined. Optimal agreement between the calculated values and experimental data was achieved by varying the parameters V, W, and β2. The found parameters agree with the previously obtained values from the scattering of protons, deuterons and α-particles. Taking into account only the quadrupole deformation extracted from the 0+ – 2+ bond, a good description of all three experimental data on elastic and inelastic scattering of the cross sections was achieved.

This article reports on the scattering of unpolarized and spin polarized electrons and positrons from 28 Ni 58 , 29 Cu 63 , 46 Pd 108 , and 78 Pt 196 , covering light to heavy precious metal targets. To cover the wide energy domain of 1 eV ≤ E i ≤ 300 MeV, Dirac partial-wave phase-shift analysis is employed, using a complex optical potential for E i ≤ 1 MeV and a potential derived from the nuclear charge distribution for E i > 1 MeV. Results are presented for the differential and integral cross-sections, including elastic, momentum transfer, and viscosity cross-sections. In addition, the inelastic, ionization, and total (elastic + inelastic) cross-section results are provided, together with mean free path estimates. Moreover, the polarization correlations S , T , and U, which are sensitive to phase-dependent interference effects, are considered. Scaling laws with respect to collision energy, scattering angle, and nuclear charge number at ultrahigh energies are derived using the equivalence between elastic scattering and tip bremsstrahlung emission. In addition, a systematic analysis of the critical minima in the differential cross-section and the corresponding total polarization points in the Sherman function S is carried out. A comparison with existing experimental data and other theoretical findings is made in order to test the merit of the present approach in explaining details of the measurements. [ABSTRACT FROM AUTHOR]

A nonlocal velocity-dependent optical potential was used to study the angular distribution of the differential cross section of nucleon–nucleus elastic scattering. The potential parameters were calculated by fitting elastic angular distributions over a wide range of energy (10-65 MeV) and mass (12-208). The real part of the local optical potential was calculated using the CDM3Y6-Paris interaction, whereas the imaginary part was a Woods-Saxon form factor and its derivative. • Optical potential. • Elastic scattering of nucleus off nucleus. • Differential cross section an analyzing power of nucleon–nucleus elastic and inelastic of scattering. [ABSTRACT FROM AUTHOR]

This article incorporates details of our calculations of the observable quantities for the scattering of electrons and positrons from a post transition metal Thallium (Tl), in the energy range of 1 eV ≤ Ei ≤ 1 MeV, using the relativistic Dirac partial wave (phase-shift) analysis employing a complex optical-potential. Absolute differential, integrated elastic and inelastic, transport, total ionization, and total cross sections and a thorough study of the critical minima in the elastic differential cross sections along with the associated angular positions of the maximum polarization points in the Sherman function are provided to study the collision dynamics. The optical potential model incorporates the interactions of the incident electron and/or positron with both the nucleus and the bound electrons of the target atom. In-depth analyses of the spin asymmetry, which are sensitive to phases related interference effect, brought on by the various ingredients of the lepton-atom interaction, are also presented. The performance of the current approach to explain the observations, with the exception of the extremely low energy domain, is shown by a comparison of the previous experimental and theoretical results on this target atom.

In this study, the available 6Li + 58Ni angular distributions in the energy range 9.9–600 MeV are reanalyzed theoretically within the framework of various interaction potentials based on both phenomenological and microscopic approaches. The well-known cluster structure of 6Li as a core of α-particle and a deuteron revolving around this core was observed and considered for generating the 6Li + 58Ni cluster folding potential. At all energies, the analyses performed within the framework of the considered potentials gave reasonable fits of data. The performed cluster folding analysis showed the necessity to reduce the potential’s strength by ~ 50–53% for describing the data fairly. The observed reduction in the strength of microscopic potential is mainly due to the dissociation of 6Li in the field of the target nucleus and consequently the high 6Li clusterization probability. The data has been also successfully reanalyzed using unrenormalized real São Paulo potential. [ABSTRACT FROM AUTHOR]

The adiabaticity assumption (AA) and the resulting concept of optical potential in the context of atom focusing with lasers were examined numerically for various experimentally controllable laser parameters. The Schrödinger equations for the atomic center‐of‐mass dynamics in a laser field were calculated using with or without the AA, and the results were compared. The validity of the AA was tested over a wide range of the Rabi frequency to detuning ratios and the optical potential depths. From the analysis, several specific guidelines were provided on choosing laser parameters that sustain the validity of the AA and improve atom focusing outcomes. [ABSTRACT FROM AUTHOR]

We use a phenomenological optical potential constructed in consideration of a versatile potential developed by Joseph N. Ginocchio. The optical potential uses less number of energy-dependent parameters to analyse nuclear scattering data. We study the ratios of elastic to Rutherford differential scattering cross sections of the system ^6 Li + ^90 Zr at various energies, namely, 10.19, 11.11, 12.07, 13.95, 15.84, 17.71, 19.60, 23.36, 28.05 and 31.87 MeV in the centre-of-mass system. The study of angular distributions is performed in a wide angular range. Our theoretical calculations explain the experimental results and follow breakup threshold anomaly phenomenon near the Coulomb barrier. We discuss the variation of reflection function |S _l | with ‘ l ’ for each contributing partial wave and calculate reaction cross section for the system against the projectile energy 31.87 MeV with permissible error.

These lectures, held at a school at the Galileo Galilei Institute for Theoretical Physics, give a survey of the formalism, the methods and achievements of nuclear direct reaction theory. After recapitulating the principles of quantum scattering theory, projection techniques are used to reduce the complexities of nuclear reactions to the manageable level of a set of a few selected coupled channels interacting via effective operators. Direct reactions are introduced as fast reactions proceeding preferentially through the excitation of doorway components of the nuclear many-body configurations, corresponding to a separation of scales in energy and momentum transfer. The concept of the optical model is introduced and applied to elastic scattering on nuclei. The coupled channel T-matrix formalism is discussed for pion-induced reactions on the nucleon. Applications of direct reaction to theory are illustrated for transfer reactions, inelastic scattering, and single and double charge exchange reactions with light and heavy ions. [ABSTRACT FROM AUTHOR]

Experimental data on elastic and inelastic scattering of 50.5 MeV a-particles and 60 MeV 3He ions by 28Si nuclei were analyzed within the framework of the standard optical model of the nucleus, in which the effect of inelastic channels is taken into account by the phenomenological introduction of an imaginary absorbing part into the interaction potential between colliding nuclei. The optimal values of the internuclear interaction potential obtained as a result of the theoretical analysis were used to study the cross sections for inelastic scattering of helium ions with the excitation of the 1.78 and 4.61 MeV states of the nucleus under study. From the analysis by the channel coupling method, where the calculation was performed taking into account both elastic and inelastic channels, the value of the quadrupole deformation parameter for a-particles ß2 = 0.37 and for 3He ions ß2 = 0.49 was determined. Optimal agreement between the calculated values and experimental data was achieved by varying the parameters V, W, and ß2. The found parameters agree with the previously obtained values from the scattering of protons, deuterons and a-particles. Taking into account only the quadrupole deformation extracted from the 0+ - 2+ bond, a good description of all three experimental data on elastic and inelastic scattering of the cross sections was achieved. [ABSTRACT FROM AUTHOR]

Kinetic equations whose solution requires the cross sections of elastic and inelastic electron scattering on atoms and molecules are used to solve numerous problems in plasma physics. To construct cross sections, modern calculations of the characteristics of resonant electron scattering are required, which are based on the use of methods operating with a complex Hamiltonian. The complex absorbing potential (CAP) method is used for a similar class of problems, but is characterized by unstable estimates of the resonance parameters. In this study, for a single-channel problem with an explicit parameterization of the scattering matrix, we analyze the features of the CAP method. It is shown that, depending on the choice of the initial conditions, there are two types of CAP-trajectories with real limits as the complex scaling factor tends to zero. The trajectories of the first type are characterized by the presence of the optimal point, and the trajectories of the second type are characterized by the presence of a closed section in the vicinity of the resonance. It is also shown that for finite values of the scaling factor, the CAP trajectory does not pass through resonance. These conclusions are qualitatively confirmed by the results of the independent application of the CAP method to the calculations of model and many-electron systems. [ABSTRACT FROM AUTHOR]

Differential, integral, momentum-transfer, viscosity, inelastic and total cross sections as well as spin asymmetries are calculated for electron and positron scattering from the gold atom with nuclear spin 32. The impact energies of the projectiles range from low-energy atomic physics regime to high-energy nuclear physics. This is accomplished by employing two different theoretical approaches, applicable for the aforesaid two domains of energies, and are based on the partial-wave analysis. In one approach, the phase shifts analysis is done at Ei

This article reports on the scattering of unpolarized and spin polarized electrons and positrons from 28Ni58,29Cu63,46Pd108, and 78Pt196, covering light to heavy precious metal targets. To cover the wide energy domain of 1 eV ≤Ei≤300 MeV, Dirac partial-wave phase-shift analysis is employed, using a complex optical potential for Ei≤1 MeV and a potential derived from the nuclear charge distribution for Ei>1 MeV. Results are presented for the differential and integral cross-sections, including elastic, momentum transfer, and viscosity cross-sections. In addition, the inelastic, ionization, and total (elastic + inelastic) cross-section results are provided, together with mean free path estimates. Moreover, the polarization correlations S,T, and U, which are sensitive to phase-dependent interference effects, are considered. Scaling laws with respect to collision energy, scattering angle, and nuclear charge number at ultrahigh energies are derived using the equivalence between elastic scattering and tip bremsstrahlung emission. In addition, a systematic analysis of the critical minima in the differential cross-section and the corresponding total polarization points in the Sherman function S is carried out. A comparison with existing experimental data and other theoretical findings is made in order to test the merit of the present approach in explaining details of the measurements.

This paper reports on the differential, integral, momentum transfer and viscosity cross sections along with spin polarisation for elastically scattered electrons and positrons from iron atoms in the incident energy ( E i ) range 1 ≤ E i ≤ 10 4 eV. In addition, we report here systematically the details of the critical minima in the elastic differential cross sections, and the absorption and total cross sections. An optical model using a complex optical potential, composed of static, exchange, polarisation and imaginary terms, is used to solve the Dirac relativistic equation in partial-wave analysis. A comparison of our evaluated cross sections with the available experimental data and other theoretical findings shows a reasonable agreement over the studied energy range. [ABSTRACT FROM AUTHOR]

This article presents an investigation into the electron impact ionization of diverse prebiotic molecules that exist within the interstellar medium. Specifically, the molecules under consideration here include ethylene glycol, ethanolamine, glycolonitrile, aminoacetonitrile, acetamide, and glycolaldehyde. These molecules hold the potential to serve as precursor compounds, playing a critical role in the formation of essential building blocks necessary for life's emergence. To understand the chemistry in these regions when such molecules interact with particles like electrons, we require reaction rates and cross sections. In this work, the electron impact ionization cross section is calculated using the robust optical potential approach and the complex scattering potential-ionization cross section method over a wide range of energies from 10 eV to 5000 eV on a fine grid. The incorporation of screening correction in this approach effectively addresses the superimposition of charge densities originating from distinct atoms within each molecule. Additionally, the binary-encounter Bethe ionization cross section is computed to facilitate comparison and validation of the presented data. [Display omitted] • Astrobiologically relevant molecules are studied upon irradiation of electron. • Complex optical potential is used to depict the electron-target interaction. • Ionization cross section of all the molecules are reported for the first time. • Two different theoretical methods CSP-ic and BEB are used for verification. • Screening correction is incorporated to increase accuracy of reported data. [ABSTRACT FROM AUTHOR]

Recent progress in the numerical solution of the nuclear many-body problem and in the development of nuclear Hamiltonians rooted in Quantum Chromodynamics, has opened the door to first-principle computations of nuclear reactions. In this article, we discuss the current status of ab initio calculations of nucleon-nucleus optical potentials for medium-mass systems, with a focus on results obtained with the coupled-cluster method.

The example of the lowest 1S resonance of the H– anion demonstrates that the resonance energy and its width calculated by way of finding the optimal point using the method of the complex absorbing potential has a systematic error, whose magnitude depends on the parameters of the absorbing potential and on the approximation used to solve the Schrödinger equation. It is shown that the accuracy of the calculation of resonance parameters can be improved if you replace finding the optimal point with averaging over the trajectory closure interval. [ABSTRACT FROM AUTHOR]

Within a macroscopic framework, the plasma-optical effect, relative to the far-infrared range, in a given narrow-gap, heavily doped and dilute, n-type semiconductor, is investigated theoretically by considering that the electron effective mass almost does not depend on the electron concentration and conceiving the corresponding dilute electronic plasma as an ensemble of quantum harmonic oscillators. Manifestly new results are obtained. In fact, the magnitude of the quantized electron velocity is calculated. In addition, the corresponding refractive index is regarded in relation to the optical potential. [ABSTRACT FROM AUTHOR]

Angular distributions of 3He elastic scattering reactions from stable Selenium isotopes have systematically calculated within the theoretical framework. Optical-model parameters for Woods-Saxon real and imaginary volume potentials have been used to illustrate the data. The corresponding ratios to Rutherford scattering and relevant barrier distributions of elastic scattering cross-sections have attained from 0° to 180°. The theoretical calculations shed light on a well-rounded definition of the empricial angular distribution data. [ABSTRACT FROM AUTHOR]

The analysis of the features of the method of complex absorbing potential (CAP) is carried out for a single-channel problem with an explicit parameterization of the scattering matrix. It is shown that there can be several types of CAP trajectories depending on the choice of the initial conditions. In any case, the estimation of the resonance parameters from the position of the optimal trajectory point can lead to a systematic error or an ambiguous result. In special cases, the search for the optimal point can be replaced by the averaging over a closed section of the trajectory. The CAP trajectories constructed in the H− and Li resonance calculations correlate well with the model trajectories, which have a curl around the resonance. The averaging over a closed area of the trajectory leads to better estimates of the energy and width of the resonance in comparison with the technique of searching for the optimal point.

Manufacturing technology for three-dimensional nano/micro-structures has been desired. In this study, we newly proposed the laser additive manufacturing method in vapor phase, by utilizing optical trapping potential to confine particles in a range smaller than diffraction limit of laser beam. In this paper, we have developed the optical trapping system with Bessel beam in order to investigate feasibility of the proposed fabrication methods. The water droplet of several µm in diameter containing particles suspended in space were successfully trapped in the optical potential of Bessel beam and then the only particles were deposited on the substrate. As a result of processing experiment, the silica particles with a diameter of 1 µm could be three dimensionally structured on the axis of the Bessel beam.

Double charge exchange (DCE) reactions could provide experimentally driven information about nuclear matrix elements of interest in the context of neutrinoless double-β decay. To achieve this goal, a detailed description of the reaction mechanism is mandatory. This requires the full characterization of the initial and final-state interactions, which are poorly known for many of the projectile-target systems involved in future DCE studies. Among these, we intend to study the 20Ne + 130Te and 18O + 116Sn systems at 15.3 AMeV, which are particularly relevant due to their connection with the 130Te→130Xe and 116Cd→116Sn double-β decays. We measure the elastic and inelastic scattering cross-section angular distributions and compare them with theoretical calculations performed in the optical model, one-step distorted wave Born approximation, and coupled-channel approaches using the São Paulo double-folding optical potential. A good description of the experimental data in the whole explored range of transferred momenta is obtained provided that couplings with the 21+ states of the projectile and target are explicitly included within the coupled-channel approach. These results are relevant also in the analysis of other quasi-elastic reaction channels in these systems, in which the same couplings should be included.

The method of impulse approximation is used to check the validity of the first-order optical potential for the elastic scattering problem of the neutron on the bound system, namely, C 1 2 (n. n) C 1 2 , Ca 4 0 (n , n) Ca 4 0 and Pb 2 0 8 (n , n) Pb 2 0 8 at incident neutron energies of 155 and 225 MeV. The optical potential is derived as the first-order term within the spectator expansion of a nonrelativistic multiple scattering terms using the Lippmann–Schwinger equation. The Modern realistic two-body potential ArgonneV18 in the momentum space was used as input in the Lippmann–Schwinger equation. The obtained results for the elastic differential cross-sections are in a good agreement with the experimental data taken from EXFOR Database for all studied targets at neutron energy above 200 MeV. As the neutron energy decreases down to approximately 155 MeV, the discrepancies with experimental data appear, which is in accordance with the impulse approximation formalism. [ABSTRACT FROM AUTHOR]

Alpha elastic scattering of p -nuclei was studied for calculating optical potentials. Choice of the α -optical potentials is important to measure the reaction rates of p -process. 1 0 6 Cd (α , α) 1 0 6 Cd and 1 1 3 In (α , α) 1 1 3 In elastic scattering cross-section data were used to determine the potential parameter sets at E lab = 1 6. 1 – 2 7 MeV for 1 0 6 Cd and E CM = 1 5. 5 9 , 18.8 MeV for 1 1 3 In system. A Wood–Saxon potential form factor is used for both real and imaginary parts. The potential parameters extracted in the present study exhibit a satisfactory result with respect to existing global potential parameters. [ABSTRACT FROM AUTHOR]

We present the first example of a rigorous uncertainty quantification on elastic nucleus-nucleus scattering at energies near the Coulomb barrier. Experimental data has been analyzed using an energy-dependent effective optical model potential with physical constraints imposed. We confirm the compatibility of these uncertainties with the well known Coulomb threshold anomaly, explained in terms of a dispersive relation, and contrast our results with previous analyses that suggest otherwise. [ABSTRACT FROM AUTHOR]

Abstract A brief overview of various approaches to the optical-model description of nuclei is presented. A survey of some of the formal aspects is given which links the Feshbach formulation for either the hole or particle Green's function to the time-ordered quantity of many-body theory. The link between the reducible self-energy and the elastic nucleon–nucleus scattering amplitude is also presented using the development of Villars. A brief summary of the essential elements of the multiple-scattering approach is also included. Several ingredients contained in the time-ordered Green's function are summarized for the formal framework of the dispersive optical model (DOM). Empirical approaches to the optical potential are reviewed with emphasis on the latest global parametrizations for nucleons and composites. Various calculations that start from an underlying realistic nucleon–nucleon interaction are discussed with emphasis on more recent work. The efficacy of the DOM is illustrated in relating nuclear structure and nuclear reaction information. Its use as an intermediate between experimental data and theoretical calculations is advocated. Applications of the use of optical models are pointed out in the context of the description of nuclear reactions other than elastic nucleon–nucleus scattering. [ABSTRACT FROM AUTHOR]