A5014524727- Nuclear physics research studies
- Quantum Chromodynamics and Particle Interactions
- Atomic and Molecular Physics
- Particle physics theoretical and experimental studies
- Quantum, superfluid, helium dynamics
- Advanced NMR Techniques and Applications
- Advanced Chemical Physics Studies
- Atomic and Subatomic Physics Research
- High-Energy Particle Collisions Research
- Cold Atom Physics and Bose-Einstein Condensates
- Nuclear Physics and Applications
- Neutrino Physics Research
- High-pressure geophysics and materials
- Superconducting Materials and Applications
- Dark Matter and Cosmic Phenomena
- Particle accelerators and beam dynamics
- Physics of Superconductivity and Magnetism
- Astronomical and nuclear sciences
- Quantum chaos and dynamical systems
- Crystallography and Radiation Phenomena
- Black Holes and Theoretical Physics
- Quantum Mechanics and Non-Hermitian Physics
- Radiation Detection and Scintillator Technologies
- Astro and Planetary Science
- Atmospheric Ozone and Climate
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa
2016-2025
Istituto Nazionale di Fisica Nucleare, Sezione di Lecce
2012-2024
University of Pisa
2007-2024
Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Gran Sasso
2024
Istituto Nazionale di Fisica Nucleare
2014-2024
University of Salento
2012-2024
Université Côte d'Azur
2024
Institut de Physique de Nice
2024
Centre National de la Recherche Scientifique
2024
University of Amsterdam
2024
In the past, several efficient methods have been developed to solve Schr\"odinger equation for four-nucleon bound states accurately. These are Faddeev-Yakubovsky, coupled-rearrangement-channel Gaussian-basis variational, stochastic hyperspherical Green's function Monte Carlo, no-core shell model, and effective interaction harmonic methods. this article we compare energy eigenvalue results some wave properties using realistic $\mathrm{AV}{8}^{\ensuremath{'}}$ NN interaction. The of all...
Spurred by the recent complete determination of weak currents in two-nucleon systems up to $\mathcal{O}{(Q}^{3})$ heavy-baryon chiral perturbation theory, we carry out a parameter-free calculation threshold S factors for solar $\mathrm{pp}$ (proton-fusion) and hep processes an effective field theory (EFT) that combines merits standard nuclear physics method systematic expansion. The power EFT adopted here is one can correlate unified formalism weak-current matrix elements two-, three-,...
A two-nucleon potential and consistent electromagnetic currents are derived in chiral effective field theory $(\ensuremath{\chi}\mathrm{EFT})$ at, respectively, ${Q}^{2}$ (or ${\mathrm{N}}^{2}\mathrm{LO}$) $eQ$ ${\mathrm{N}}^{3}\mathrm{LO}$), where $Q$ generically denotes the low-momentum scale $e$ is electric charge. Dimensional regularization used to renormalize pion-loop corrections. simple expression for magnetic dipole $(M1)$ operator associated with pion loops, consisting of two terms,...
The hyperspherical harmonic (HH) method has been widely applied in recent times to the study of bound states, using Rayleigh-Ritz variational principle, and low-energy scattering processes, Kohn A=3 4 nuclear systems. When wave function system is expanded over a sufficiently large set HH basis functions, containing or not correlation factors, quite accurate results can be obtained for observables interest. In this paper, main aspects are discussed together with its application zero-energy...
In recent years local chiral interactions have been derived and implemented in quantum Monte Carlo methods order to test what extent the effective field theory framework impacts our knowledge of few- many-body systems. this Letter, we present Green's function calculations light nuclei based on family two-body presented by group a previous paper conjunction with three-body fitted bound- scattering-state observables three-nucleon sector. These include Δ intermediate states their...
We present fully local versions of the minimally nonlocal nucleon-nucleon potentials constructed in a previous paper [Piarulli et al., Phys. Rev. C 91, 024003 (2015)], and use them hypersperical harmonics quantum Monte Carlo calculations ground excited states $^{3}\mathrm{H}$, $^{3}\mathrm{He}$, $^{4}\mathrm{He}$, $^{6}\mathrm{He}$, $^{6}\mathrm{Li}$ nuclei. The long-range part these includes one- two-pion exchange contributions without with $\mathrm{\ensuremath{\Delta}}$ isobars...
Background: The $A=2$ and 3 form factors are among the observables of choice for testing models nuclear interactions associated electromagnetic charge current operators. Here we investigate validity chiral-effective-field-theory ($\ensuremath{\chi}$EFT) approach to describe strong-interaction dynamics in these few-nucleon systems their response probes.Purpose: objectives present work twofold. first is address resolve some differences independent, $\ensuremath{\chi}$EFT derivations up one...
The astrophysical S factor for the radiative capture d(p,γ)^{3}He in energy range of interest big bang nucleosynthesis (BBN) is calculated using an ab initio approach. nuclear Hamiltonian retains both two- and three-nucleon interactions-the Argonne v_{18} Urbana IX, respectively. Both one- many-body contributions to current operator are included. former retain first time, besides 1/m leading order contribution (m nucleon mass), also next-to-leading term, proportional 1/m^{3}. currents...
For the first time, we approach in this work problem of renormalization Gamow-Teller decay operator for nuclear shell-model calculations by way many-body perturbation theory, starting from a Hamiltonian and electroweak currents derived consistently chiral theory. These are inputs need to construct microscopically effective Hamiltonians operators. The goal is assess role both correlations as origins well-known quenching axial coupling constant ${g}_{A}$. To end, calculation observables...
Different models for conserved two- and three-body electromagnetic currents are constructed from three-nucleon interactions, using either meson-exchange mechanisms or minimal substitution in the momentum dependence of these interactions. The connection between two different schemes is elucidated. A number low-energy electronuclear observables, including (i) np radiative capture at thermal neutron energies deuteron photodisintegration low energies, (ii) nd pd reactions, (iii) isoscalar...
We obtain a minimal form of the two-derivative three-nucleon contact Lagrangian, by imposing all constraints deriving from discrete symmetries, Fierz identities and Poincare' covariance. The resulting interaction, depending on 13 unknown low-energy constants, leads to potential which we give in local configuration space. also consider leading (no-derivative) four-nucleon interaction show that there exists only one independent operator.
The muon-capture reactions $^{2}\mathrm{H}({\ensuremath{\mu}}^{\ensuremath{-}},{\ensuremath{\nu}}_{\ensuremath{\mu}})nn$ and $^{3}\mathrm{He}({\ensuremath{\mu}}^{\ensuremath{-}},{\ensuremath{\nu}}_{\ensuremath{\mu}})^{3}\mathrm{H}$ are studied with nuclear potentials charge-changing weak currents, derived in chiral effective field theory. low-energy constants (LECs) ${c}_{D}$ ${c}_{E}$, present the three-nucleon potential (${c}_{D}$) axial-vector current, constrained to reproduce $A=3$...
The electromagnetic charge operator in a two-nucleon system is derived chiral effective field theory ($\chi$EFT) up to order $e\, Q$ (or N4LO), where $Q$ denotes the low-momentum scale and $e$ electric charge. specific form of N3LO N4LO corrections from, respectively, one-pion-exchange two-pion-exchange depends on off-the-energy-shell prescriptions adopted for non-static terms corresponding potentials. We show that different lead unitarily equivalent potentials accompanying operators. Thus,...
We present a detailed study of the effect different three-nucleon interactions in $p$-$^{3}\mathrm{He}$ elastic scattering at low energies. In particular, two have been considered: one derived from effective field theory next-to-next-to-leading order and more phenomenological point view---the so-called Illinois model. The four-nucleon observables are calculated by using Kohn variational principle hyperspherical harmonics technique, results compared with available experimental data. found...
The Gamow-Teller (GT) matrix element contributing to tritium $\beta$ decay is calculated with trinucleon wave functions obtained from hyperspherical-harmonics solutions of the Schr\"odinger equation chiral two- and three-nucleon interactions including $\Delta$ intermediate states that have recently been constructed in configuration space. Predictions up N3LO expansion axial current (with $\Delta$'s) overestimate empirical value by 1--4 \%. By exploiting relation between low-energy constant...
Two-nucleon axial charge and current operators are derived in chiral effective field theory up to one loop. The derivation is based on time-ordered perturbation accounts for cancellations between the contributions of irreducible diagrams owing nonstatic corrections from energy denominators reducible diagrams. Ultraviolet divergencies associated with loop isolated dimensional regularization. resulting finite conserved limit, while requires renormalization. A complete set contact terms...
The PTOLEMY project aims to develop a scalable design for Cosmic Neutrino Background (CNB) detector, the first of its kind and only one conceived that can look directly at image Universe encoded in neutrino background produced second after Big Bang. scope work next three years is complete conceptual this detector validate with direct measurements non-neutrino backgrounds are below expected cosmological signal. In paper we discuss details theoretical aspects experiment physics goals....
We discuss the consequences of quantum uncertainty on spectrum electron emitted by $\ensuremath{\beta}$-processes a tritium atom bound to graphene sheet. analyze quantitatively issue recently raised Cheipesh, Cheianov, and Boyarsky [Phys. Rev. D 104, 116004 (2021)], relevant timescales degrees freedom that can contribute intrinsic spread in energy. perform careful calculations potential between with different coverages geometries. With this at hand, we propose possible avenues mitigate...
The present work deals with ${e}^{+}\text{\ensuremath{-}}{e}^{\ensuremath{-}}$ pair production in the four-nucleon system. We first analyze process as a purely electromagnetic one context of state-of-the-art approach to nuclear strong-interaction dynamics and currents, derived from chiral effective field theory $(\ensuremath{\chi}\mathrm{EFT})$. Next, we examine how exchange hypothetical low-mass boson would impact cross section for such process. consider several possibilities, that this is...
Differential and total breakup cross sections as well vector tensor analyzing powers for $p\ensuremath{-}d$ scattering are studied energies above the deuteron threshold up to ${E}_{\mathrm{lab}}=28 \mathrm{MeV}.$ The wave function is expanded in terms of correlated hyperspherical harmonic basis elastic S matrix obtained using Kohn variational principle its complex form. effects Coulomb interaction, which expected be important this energy range, have been rigorously taken into account....
The cross section for the proton weak capture reaction ${}^{1}\mathrm{H}{(p,e}^{+}{\ensuremath{\nu}}_{e}{)}^{2}\mathrm{H}$ is calculated with wave functions obtained from a number of modern, realistic high-precision interactions. To minimize uncertainty in axial two-body current operator, its matrix element has been adjusted to reproduce measured Gamow-Teller tritium $\ensuremath{\beta}$ decay model calculations using trinucleon these A thorough analysis ambiguities that this procedure...