E. Moya De Guerra

• Professor
• Professor Emeritus at Complutense University of Madrid

A different alternative approach to calculate the ratio of the surface to volume components of the nuclear symmetry energy is proposed in the framework of the coherent density fluctuation model (CDFM). An alternate expression (scheme II) for the ratio is derived consistently within the model. This expression appears in a form more direct and physic...

A new alternative approach to calculate the ratio of the surface to volume components of the nuclear symmetry energy is proposed in the framework of the coherent density fluctuation model (CDFM). A new expression (scheme II) for the ratio is derived consistently within the model. This expression appears in a form more direct and physically motivate...

Backward elastic electron scattering from odd-A nuclear targets is characterized by magnetic form factors containing precise information on the nuclear structure. We study the sensitivity of the magnetic form factors to structural effects related to the evolution and shape transitions in both isotopic and isotonic chains. Calculations of magnetic f...

Backward elastic electron scattering from odd-A nuclear targets is characterized by magnetic form factors containing precise information on the nuclear structure. We study the sensitivity of the magnetic form factors to structural effects related to the evolution and shape transitions in both isotopic and isotonic chains. Calculations of magnetic f...

The neutron skin of nuclei is an important fundamental property, but its accurate measurement faces many challenges. Inspired by charge symmetry of nuclear forces, the neutron skin of a neutron-rich nucleus is related to the difference between the charge radii of the corresponding mirror nuclei. We investigate this relation within the framework of...

The neutron skin of nuclei is an important fundamental property, but its accurate measurement faces many challenges. Inspired by charge symmetry of nuclear forces, the neutron skin of a neutron-rich nucleus is related to the difference between the charge radii of the corresponding mirror nuclei. We investigate this relation within the framework of...

The neutron skin of nuclei is an important fundamental property, but its accurate measurement faces many challenges. Inspired by charge symmetry of nuclear forces, the neutron skin of a neutron-rich nucleus is related to the difference between the charge radii of the corresponding mirror nuclei. We investigate this relation within the framework of...

We derive the values of nuclear symmetry energy, its components, as well as pressure in finite nuclei at saturation density from their corresponding values in nuclear matter obtained in nonrelativistic Brueckner-Hartree-Fock calculations with the realistic Bonn B and Bonn CD potentials using the coherent density fluctuation model in the framework o...

We derive the values of nuclear symmetry energy, its components, as well as pressure in finite nuclei at saturation density from their corresponding values in nuclear matter obtained in non-relativistic Brueckner-Hartree-Fock calculations with the realistic Bonn B and Bonn CD potentials using the coherent density fluctuation model in the framework...

We investigate the temperature dependence of the volume and surface components of the nuclear symmetry energy (NSE) and their ratio in the framework of the local density approximation. The results of these quantities for finite nuclei are obtained within the coherent density fluctuation model (CDFM). The CDFM weight function is obtained using the t...

Magnetic form factors from odd-A spherical and deformed nuclei corresponding to elastic electron scattering are calculated in the plane-wave Born approximation. The nuclear structure of the target is described within a deformed self-consistent mean-field calculation with effective interactions of Skyrme type and pairing correlations in the BCS appr...

Magnetic form factors corresponding to elastic electron scattering from odd-A nuclei are presented. The calculations are carried out in plane-wave Born approximation. The one-body properties are obtained in a deformed self-consistent mean-field calculation based on a Skyrme HF+BCS method. Collective effects are also included in the cranking approxi...

The temperature dependence of the volume and surface components of the nuclear symmetry energy (NSE) and their ratio is investigated in the framework of the local density approximation. The results of these quantities for finite nuclei are obtained within the coherent density fluctuation model (CDFM). The CDFM weight function is obtained using the...

The temperature dependence of the volume and surface components of the nuclear symmetry energy (NSE) and their ratio is investigated in the framework of the local density approximation (LDA). The results of these quantities for finite nuclei are obtained within the coherent density fluctuation model (CDFM). The CDFM weight function is obtained usin...

We derive the volume and surface components of the nuclear symmetry energy (NSE) and their ratio within the coherent density fluctuation model. The estimations use the results of the model for the NSE in finite nuclei based on the Brueckner and Skyrme energy-density functionals for nuclear matter. The obtained values of the volume and surface contr...

DOI:https://doi.org/10.1103/PhysRevC.95.039903

The temperature dependence of the symmetry energy for isotopic chains of even-even Ni, Sn, and Pb nuclei is investigated in the framework of the local density approximation (LDA). The Skyrme energy density functional with two Skyrme-class effective interactions, SkM* and SLy4, is used in the calculations. The temperature-dependent proton and neutro...

The temperature dependence of the symmetry energy for isotopic chains of even-even Ni, Sn, and Pb nuclei is investigated in the framework of the local density approximation (LDA). The Skyrme energy density functional with two Skyrme-class effective interactions, SkM* and SLy4, is used in the calculations. The temperature-dependent proton and neutro...

We study the two-neutrino double-beta decay in 76Ge, 116Cd, 128Te, 130Te, and 150Nd, as well as the two Gamow-Teller branches that connect the double-beta decay partners with the states in the intermediate nuclei. We use a theoretical microscopic approach based on a deformed selfconsistent mean field with Skyrme interactions including pairing and s...

We study the two-neutrino double-beta decay in 76Ge, 116Cd, 128Te, 130Te, and 150Nd, as well as the two Gamow-Teller branches that connect the double-beta decay partners with the states in the intermediate nuclei. We use a theoretical microscopic approach based on a deformed selfconsistent mean field with Skyrme interactions including pairing and s...

The volume and surface components of the nuclear symmetry energy (NSE) and their ratio are calculated within the coherent density fluctuation model (CDFM). The estimations use the results of the model for the NSE in finite nuclei based on the Brueckner energy-density functional for nuclear matter. In addition, we present results for the NSE and its...

The volume and surface components of the nuclear symmetry energy (NSE) and their ratio are calculated within the coherent density fluctuation model (CDFM). The estimations use the results of the model for the NSE in finite nuclei based on the Brueckner energy-density functional for nuclear matter. In addition, we present results for the NSE and its...

We briefly review the motivation to search for sterile neutrinos in the keV mass scale, as dark matter candidates, and the prospects to find them in beta decay or electron capture spectra, with a global perspective. We describe the fundamentals of the neutrino flavor-mass eigenstate mismatch that opens the possibility of detecting sterile neutrinos...

SuperScaling model (SuSA) predictions to neutrino-induced charged-current π+ production in the Δ-resonance region are explored under MiniBooNE experimental conditions. The SuSA charged-current π+ results are in good agreement with data on neutrino flux-averaged double-differential cross sections. The SuSA model for quasielastic scattering and its e...

We study various ground-state properties of neutron-rich and neutron-deficient Mg isotopes with A=20-36 in the framework of the self-consistent deformed Skyrme-Hartree- Fock plus BCS method. The nuclear symmetry energy is investigated for the same isotopic chain following the theoretical approach based on the coherent density fluctuation model. The...

SuperScaling model (SuSA) predictions to neutrino-induced charged-current π⁺ production in the Δ-resonance region are explored under MiniBooNE experimental conditions. The SuSA charged-current π⁺ results are in good agreement with data on neutrino flux-averaged double-differential cross sections. The SuSA model for quasielastic scattering and its e...

We briefly review the motivation to search for sterile neutrinos in the keV mass scale, as dark matter candidates, and the prospects to find them in beta decay or electron capture spectra. We describe the fundamentals of the neutrino flavor-mass eigenstate mismatch that opens the possibility of detecting sterile neutrinos in such ordinary nuclear p...

Neutron-deficient isotopes in the lead region are well established examples of the shape coexistence phenomenon in nuclei. In this work, bulk and decay properties, including deformation energy curves, charge mean square radii, Gamow-Teller (GT) strength distributions, and β-decay half-lives, are studied in neutron-deficient Pt, Hg, and Pb isotopes....

Neutral current quasielastic (anti)neutrino scattering cross sections on a $^{12}$C target are analyzed using a realistic spectral function $S(p,E)$ that gives a scaling function in accordance with the ($e,e'$) scattering data. The spectral function accounts for the nucleon-nucleon (NN) correlations by using natural orbitals (NOs) from the Jastrow...

Recent progresses on the relativistic modeling of neutrino-nucleus reactions are presented and the results are compared with high precision experimental data in a wide energy range.

The symmetry energy, the neutron pressure and the asymmetric compressibility of spherical Ni, Sn, Pb and deformed Kr, Sm neutron-rich even-even nuclei are calculated within the coherent density fluctuation model using the symmetry energy as a function of density within the Brueckner energy-density functional. The correlation between the thickness o...

The symmetry energy, the neutron pressure and the asymmetric compressibility of spherical Ni, Sn, and Pb and deformed Kr and Sm neutron-rich even-even nuclei are calculated within the coherent density fluctuation model using the symmetry energy as a function of density within the Brueckner energy-density functional. The correlation between the thic...

A comprehensive study of various ground-state properties of neutron-rich and neutron-deficient Mg isotopes with $A$=20-36 is performed in the framework of the self-consistent deformed Skyrme-Hartree-Fock plus BCS method. The correlation between the skin thickness and the characteristics related with the density dependence of the nuclear symmetry en...

Charge-current quasielastic (CCQE) (anti)neutrino scattering cross sections on a $^{12}$C target are analyzed using a spectral function $S(p,{\cal E})$ that gives a scaling function in accordance with the ($e,e'$) scattering data. The spectral function accounts for the nucleon-nucleon (NN) correlations, it has a realistic energy dependence and natu...

We present a theoretical analysis of the single-state dominance hypothesis for the two-neutrino double-beta decay process. The theoretical framework is a proton-neutron QRPA based on a deformed Hartree-Fock mean field with BCS pairing correlations. We focus on the decays of 100Mo, 116Cd and 128Te. We do not find clear evidences for single-state dom...

We study the spectra of the emitted charged leptons in charge current weak nuclear processes to analyze the effect of neutrino masses. Standard active neutrinos are studied here, with masses of the order of 1 eV or lower, as well as sterile neutrinos with masses of a few keV. The latter are warm dark matter (WDM) candidates hypothetically produced...

keV sterile neutrinos are important as extensions of the Standard Model of particle physics and as serious keV dark matter (DM) candidates (Warm DM) in agreement with both cosmological and galaxy observations. We study the possible detection of a keV sterile neutrino through its mixing with a light active neutrino in the Rhenium 187 and Tritium bet...

We investigate the Gamow-Teller (GT) strength distributions in the double-β decaying nuclei 128Te and 130Te, as well as in their respective partners 128Xe and 130Xe. Theoretical calculations based on a deformed quasiparticle random phase approximation built on Skyrme selfconsistent mean fields are compared with measured GT- strength distributions e...

The weak interaction between an atomic nucleus and the orbiting electrons is responsible for small parity mixings in the electron wave functions that give rise to atomic transitions forbidden between pure-parity states. The degree of the parity mixing, and thus the strength of the nominally forbidden atomic transitions, depends on the weak charge o...

We investigate the Gamow-Teller (GT) strength distributions in the double-beta decaying nuclei Te-128 and Te-130, as well as in their respective partners Xe-128 and Xe-130. Theoretical calculations based on a deformed quasiparticle random phase approximation built on Skyrme selfconsistent mean fields are compared with measured GT(-) strength distri...

The symmetry energy, the neutron pressure and the asymmetric compressibility of deformed neutron-rich even-even nuclei are calculated on the examples of Kr and Sm isotopes within the coherent density fluctuation model using the symmetry energy as a function of density within the Brueckner energy-density functional. The correlation between the thick...

We study some relevant aspects of complex nuclei structure using electroweak probes within the framework of self-consistent mean field theories with Skyrme density-dependent two-body interactions, including pairing and spin-isospin RPA correlations where necessary. We apply the formalism to the study of single and double beta decays as normal modes...

Superscaling approximation (SuSA) predictions to neutrino-induced charged-current charged pion production in the \Delta-resonance region are explored under MiniBooNE experimental conditions. The results obtained within SuSA for the flux-averaged double-differential cross sections of the \pi+ production for the \nu_\mu+CH_2 reaction as a function of...

We study Gamow-Teller strength distributions within a QRPA approach performed on top of a deformed Skyrme-Hartree-Fock+BCS single particle basis with the inclusion of residual spin-isospin interactions in both particle-hole and particle-particle channels. We focus our attention in several problems of interest in Nuclear Structure and Nuclear Astrop...

We analyze the active‐shell occupation probabilities of 76 Ge and their contribution to the single‐ and double‐beta decay matrix elements of this isotope. Strength modifications of the nucleon spin‐orbit interaction are introduced for a better comparison with experimental data. The relation of this spin‐orbit interaction with the nucleon densit...

We study electroweak processes in complex nuclei within the framework of self‐consistent mean field theories including pairing and RPA correlations. We review the adiabatic time dependent Hartree‐Fock (HF) theory and its ability to simultaneously handle large and small amplitude modes. We apply the formalism to the study of single and double beta d...

We analyze parity-violating elastic electron scattering as a complementary tool for precise determination of neutron densities in nuclei. In particular we discuss how to extract the ratio between neutron and proton rms radii and monopole form factors from theoretical and experimental asymmetries. The structure of the nuclear target is obtained from...

We review the Skyrme interaction as first used by Vautherin and Brink in the Hartree-Fock (HF) formalism to construct the energy density functional and more specifically, the two-body spin-orbit term. Problems with this term were already pointed out by Skyrme himself and have been discussed in the past years by other authors. We present examples wh...

Sterile neutrinos with mass in the range of one to a few keV are important as extensions of the Standard Model of particle physics and are serious dark matter (DM) candidates. This DM mass scale (warm DM) is in agreement with both cosmological and galactic observations. We study the role of a keV sterile neutrino through its mixing with a light act...

We study the correlation between the thickness of the neutron skin in finite nuclei and the nuclear symmetry energy for isotopic chains of even-even Ni, Sn, and Pb nuclei in the framework of the deformed self-consistent mean-field Skyrme HF+BCS method. The symmetry energy, the neutron pressure and the asymmetric compressibility in finite nuclei are...

The electron–ion scattering experiment ELISe is part of the installations envisaged at the new experimental storage ring at the International Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany. It offers an unique opportunity to use electrons as probe in investigations of the structure of exotic nuclei. The conceptual design and...

The relativistic distorted-wave impulse approximation is used to describe the 3He(e, e′ p)2H process. We describe the 3He nucleus within the adiabatic hyperspherical expansion method with realistic nucleon-nucleon interactions. The overlap between the 3He and the deuteron wave functions can be accurately computed from a three-body calculation. The...

The link between the scaling function extracted from the analysis of (e,e') cross sections and the spectral function/momentum distribution in nuclei is revisited. Several descriptions of the spectral function based on the independent particle model are employed, together with the inclusion of nucleon correlations, and effects of the energy dependen...

We discuss parity-violating elastic electron scattering as a complementary tool in the race for more precise determinations of neutron densities in nuclei. Isovector and isoscalar densities and form factors in N > Z and N = Z stable nuclei are discussed taking 208Pb and 28Si as examples. Distorted wave calculations of parity-violating asymmetries a...

Usual Woods-Saxon single-particle levels with BCS pairing are not able to reproduce the experimental occupation probabilities of the proton and neutron levels 1p3/2, 1p1/2, 0f5/2, and 0g9/2 in the double-β decay system 76Ge to 76Se. Shifting down the 0g9/2 level by hand can explain the data, but it is not satisfactory. Here it is shown that a self-...

The single state dominance hypothesis for the two-neutrino double-beta decay matrix elements is tested in this work for the double-beta decaying nuclei 100Mo, 116Cd, and 128Te. In addition to this, we analyze the contribution to the double-beta matrix elements from the low-lying intermediate states and from the whole set of intermediate states. We...

It is shown that superscaling is due to the high-momentum tail of the nucleon momentum distribution n(k) which is similar for all nuclei and is caused by the short-range and tensor nucleon-nucleon correlations. It is pointed out also that superscaling gives information about the general power-law asymptotics of n(k) and the nucleon-nucleon forces i...

The Generalized Coherent State Model, proposed previously for a unified description of magnetic and electric collective properties of nuclear systems, is used to study the ground state band charge density as well as the E0 transitions from $0^+_{\beta}$ to $0^+_g$. The influence of the nuclear deformation and of angular momentum projection on the c...

A sixth-order quadrupole boson Hamiltonian is used to describe the states $0^+$ and $2^+$ identified in several nuclei by various types of experiments. Two alternative descriptions of energy levels are proposed. One corresponds to a semi-classical approach of the model Hamiltonian while the other one provides the exact eigenvalues. Both procedures...

We study nucleon momentum distributions of even-even isotopes of Ni, Kr, and Sn in the framework of deformed self-consistent mean-field Skyrme HF+BCS method, as well as of theoretical correlation methods based on light-front dynamics and local density approximation. The isotopic sensitivities of the calculated neutron and proton momentum distributi...

We study the validity of the single-state dominance hypothesis for the two-neutrino double-beta decay matrix elements within a proton-neutron QRPA calculation based on a deformed Skyrme Hartree-Fock mean field with pairing correlations. We also study the contributions from all excited states in the intermediate nucleus to the double-beta matrix ele...

We extend our previous description of the superscaling phenomenon in inclusive electron scattering within the Coherent Density Fluctuation Model (CDFM). This model is a natural extension to finite nuclei of the Relativistic Fermi Gas Model (RFG) within which the scaling variable $\psi^{\prime}$ was introduced. In this work we propose a new modified...

A theoretical analysis of the single-state dominance hypothesis for the two-neutrino double-beta decay rates is performed on the examples of the double-beta decays of 100Mo, 116Cd, and 128Te. We also test the validity of an extended low-lying-state dominance that takes into account the contributions of the low-lying excited states in the intermedia...

A theoretical analysis of the single-state dominance hypothesis for the two-neutrino double-beta decay rates is performed on the examples of the double-beta decays of 100Mo, 116Cd and 128Te. We also test the validity of an extended low-lying-state dominance that takes into account the contributions of the low-lying excited states in the intermediat...

We present an optimization scheme that employs a Genetic Algorithm (GA) to determine the properties of low-lying nucleon excitations within a realistic photo-pion production model based upon an effective Lagrangian. We show that with this modern optimization technique it is possible to reliably assess the parameters of the resonances and the associ...

The influence of nuclear isospin mixing on parity-violating elastic electron scattering is studied for the even–even, N=Z nuclei 12C, 24Mg, 28Si, and 32S. Their ground-state wave functions have been obtained using a self-consistent axially-symmetric mean-field approximation with density-dependent effective two-body Skyrme interactions. Some differe...

The development of neutron skins as a function of the neutron number is investigated within a self-consistent framework based on deformed Hartree-Fock calculations with density dependent Skyrme forces and pairing correlations in BCS approximation. We study several isotopic chains and consider all the experimentally observed isotopes from neutron-de...

Recent results are presented for quasifree pion photoproduction off the deuteron in the energy region from threshold up to the Δ(1232)‐resonance with inclusion of all leading πNN effects. Final‐state interaction effects are investigated and their role in polarized and unpolarized observables are found to be significant. The sensitivity of result...

The superscaling analysis using the scaling function obtained within the coherent density fluctuation model is extended to calculate charge-changing neutrino and antineutrino scattering on $^{12}$C at energies from 1 to 2 GeV not only in the quasielastic but also in the delta excitation region. The results are compared with those obtained using the...

We investigate the importance of crossing symmetry in effective field models and the effects of phenomenological nucleon resonance widths on the paradigmatic case of pion photoproduction. We use reaction models containing four star resonances up to 1.8 Gev ($\Delta$(1232), N(1440), N(1520), N(1535), $\Delta$(1620), N(1650), $\Delta$(1700), and N(17...

In these talks, we review non relativistic selfconsistent mean field theories, their scope and limitations. We first discuss static and time dependent mean field approaches for particles and quasiparticles, together with applications. We then discuss extensions that go beyond the non-relativistic independent particle limit. On the one hand, we cons...

A study of the charge and matter densities and the corresponding rms radii for even-even isotopes of Ni, Kr, and Sn has been performed in the framework of deformed self-consistent mean field Skyrme HF+BCS method. The resulting charge radii and neutron skin thicknesses of these nuclei are compared with available experimental data, as well as with ot...

The helicity dependence of the -vectord-vectorpp,-vectord-vector{sup +}nn, and -vectord-vector°np reaction channels is studied for incident photon energies from threshold up to the (1232) resonance with inclusion of leading NN effects. The doubly polarized total and differential cross sections for parallel and antiparallel helicity states are predi...

We analyze the γp→ηp process from threshold up to 1.2 GeV, employing an effective Lagrangian approach that allows for a mixing of eta couplings of pseudoscalar and pseudovector nature. The mixing ratio of the couplings may serve as a quantitative estimation of the SUL(3)×SUR(3) extended chiral symmetry violation in this energy regime. The data anal...

The superscaling analysis is extended to include quasielastic (QE) scattering via the weak neutral current of neutrinos and antineutrinos from nuclei. The scaling function obtained within the coherent density fluctuation model (used previously in calculations of QE inclusive electron and charge-changing (CC) neutrino scattering) is applied to neutr...

Superscaling analyses of inclusive electron scattering from nuclei are extended from the quasielastic processes to the delta-excitation region. The calculations of both quasielastic and delta longitudinal and transverse response functions as well as of (e, e� ) cross sections for 12C at various incident electron energies are performed in approaches...

The superscaling observed in inclusive electron scattering is described within the dilute Fermi gas model with interaction between the particles. The comparison with the relativistic Fermi gas (RFG) model without interaction shows an improvement in the explanation of the scaling function $f(\psi ')$ in the region $\psi ' < -1$, where the RFG result...

We present an extraction of the E2/M1 ratio of the Δ(1232) from experimental data applying an effective Lagrangian model. We compare the result obtained with different nucleonic models and we reconcile the experimental results with the lattice QCD calculations.

Gamow-Teller and Fermi transitions are considered in a HF+BCS+pnQRPA theoretical framework. We show here how Gamow-Teller strength distributions can be used in a search for signatures of nuclear deformation in neutron deficient Pb, Hg and Po isotopes, as well as how Fermi transitions allow us to quantify isospin mixing in some even Kr isotopes arou...

Superscaling analyses of inclusive electron scattering from nuclei are extended from the quasielastic processes to the delta excitation region. The calculations of $(e,e^\prime)$ cross sections for the target nucleus $^{12}$C at various incident electron energies are performed using scaling functions $f(\psi^{\prime})$ obtained in approaches going...

The energy distributions of the Gamow-Teller strength are studied for even-even Xe isotopes with mass numbers from 124 to 142. A self-consistent microscopic formalism is used to generate the single particle basis, using a deformed Skyrme Hartree-Fock mean field with pairing correlations in BCS approximation. The Gamow-Teller transitions are obtaine...