254 citations · 3k across the 66 of their papers we have counts for
50 papers · 1 filter
A new analysis of the "hep" S-factor and the "hen" cross section
Michele Viviani, Alex Gnech, Laura Elisa Marcucci +2
We present a new accurate analysis of the HeHe (''hep'') reaction at astrophysical energies. The S-factor is computed using a state-of-the-art method to calcu…
Partial-wave decomposition of isospin-projected subleading three-nucleon contact interactions
Elena Filandri, Luca Girlanda, Ylenia Capitani
We analyze the subleading three-nucleon contact interaction terms at N4LO in chiral effective field theory. We perform the isospin projection into and states, and f…
The 3- and 4- particle systems within short-range Effective Field Theory
E. Filandri, M. Viviani, L. Girlanda +2
and nuclei represent essential elements for life on Earth. The study of their formation plays a key role in understanding heavy element nucleosynt…
The X17 boson and the d(p,e+ e-)3He and d(n,e+ e-)3H processes: a theoretical analysis
M. Viviani, E. Filandri, L. Girlanda +3
The present work deals with the e+ e- pair production in the d(p,e+e-)3He and d(n,e+ e-)3H processes, in order to evidentiate possible effects due to the exchange of a hypothetical…
Study of the alpha-particle monopole transition form factor
M. Viviani, A. Kievsky, L. E. Marcucci +1
The 4He monopole form factor is studied by computing the transition matrix element of the electromagnetic charge operator between the 4He ground-state and the p+3H and n+3He scatte…
Momentum dependent nucleon-nucleon contact interactions and their effect on p-d scattering observables
E. Filandri, L. Girlanda, A. Kievsky +2
Starting from a complete set of relativistic nucleon-nucleon contact operators up to order of the expansion in the soft (relative or nucleon) momentum , we show that no…
Relativistic constraints on 3N contact interactions
Alessia Nasoni, Elena Filandri, Luca Girlanda
In this paper we analyze the relativistic corrections to the leading order three-nucleon (3N) contact interactions. These boost corrections are derived first from the nonrelativist…
Momentum dependent nucleon-nucleon contact interaction from a relativistic Lagrangian
E. Filandri, L. Girlanda
A complete set of parity- and time-reversal conserving relativistic nucleon-nucleon contact operators is identified up to the order of the expansion in soft momenta . A…
Effect of the N3LO three-nucleon contact interaction on p-d scattering observables
L. Girlanda, E. Filandri, A. Kievsky +2
A unitary transformation allows to remove redundant terms in the two-nucleon (2N) contact interaction at the fourth order (N3LO) in the low-energy expansion of Chiral Effective Fie…
Theoretical study of the d(d,p)3H and d(d,n)3He processes at low energies
M. Viviani, L. Girlanda, A. Kievsky +2
We present a theoretical study of the processes d(d,p)3H and d(d,n)3He at energies of interest for energy production and for big-bang nucleosynthesis. We accurately solve the four…
The X17 boson and the HHe and HeHe processes: a theoretical analysis
M. Viviani, E. Filandri, L. Girlanda +4
The present work deals with - pair production in the four-nucleon system. We first analyze the process as a purely electromagnetic one in the context of a state-of-the-ar…
Efimov Physics and Connections to Nuclear Physics
A. Kievsky, L. Girlanda, M. Gattobigio +1
Physical systems characterized by a shallow two-body bound or virtual state are governed at large distances by a continuous-scale invariance, which is broken to a discrete one when…
Two- and three-nucleon contact interactions and ground-state energies of light- and medium-mass nuclei
R. Schiavilla, L. Girlanda, A. Gnech +5
Classes of two-nucleon () contact interactions are developed in configuration space at leading order (LO), next-to-leading order (NLO), and next-to-next-to-next-to-leading orde…
Unitary ambiguity of NN contact interactions and the 3N force
L. Girlanda, A. Kievsky, L. E. Marcucci +1
We identify a redundancy between two- and three-nucleon contact interactions at the fourth and fifth order of the chiral expansion respectively. In particular we show that tensor-t…
Study of H, He, H, and He scattering with the HH method
M. Viviani, L. Girlanda, A. Kievsky +1
The H, He, H, and He elastic and charge exchange reactions at low energies are studied by means of the hyperspherical harmonic method. The considere…
Parity- and time-reversal-violating nuclear forces
J. de Vries, E. Epelbaum, L. Girlanda +3
Parity-violating and time-reversal conserving (PVTC) and parity-violating and time-reversal-violating (PVTV) forces in nuclei form only a tiny component of the total interaction be…
The Hyperspherical Harmonics method: a tool for testing and improving nuclear interaction models
L. E. Marcucci, J. Dohet-Eraly, L. Girlanda +3
The Hyperspherical Harmonics (HH) method is one of the most accurate techniques to solve the quantum mechanical problem for nuclear systems with . In particular, by applyin…
Short-range three-nucleon interaction from A=3 data and its hierarchical structure
L. Girlanda, A. Kievsky, M. Viviani +1
We construct accurate models of three-nucleon (3N) interaction by fitting, in a hybrid phenomenological approach, the low-energy constants parametrizing the subleading 3N contact o…
Local chiral interactions and magnetic structure of few-nucleon systems
R. Schiavilla, A. Baroni, S. Pastore +8
The magnetic form factors of H, H, and He, deuteron photodisintegration cross sections at low energies, and deuteron threshold electrodisintegration cross sections at b…
Correlations imposed by the unitary limit between few-nucleon systems, nuclear matter and neutron stars
A. Kievsky, M. Viviani, D. Logoteta +2
The large values of the singlet and triplet two-nucleon scattering lengths locate the nuclear system close to the unitary limit. This particular position strongly constrains the lo…
Local chiral interactions, the tritium Gamow-Teller matrix element, and the three-nucleon contact term
A. Baroni, R. Schiavilla, L. E. Marcucci +8
The Gamow-Teller (GT) matrix element contributing to tritium decay is calculated with trinucleon wave functions obtained from hyperspherical-harmonics solutions of the Schrödin…
Light-nuclei spectra from chiral dynamics
M. Piarulli, A. Baroni, L. Girlanda +8
A major goal of nuclear theory is to explain the spectra and stability of nuclei in terms of effective many-body interactions amongst the nucleus' constituents-the nucleons, i.e.,…
Implications of Efimov physics for the description of three and four nucleons in chiral effective field theory
A. Kievsky, M. Viviani, M. Gattobigio +1
In chiral effective field theory the leading order (LO) nucleon-nucleon potential includes two contact terms, in the two spin channels , and the one-pion-exchange potential.…
Local chiral potentials and the structure of light nuclei
Maria Piarulli, Luca Girlanda, Rocco Schiavilla +6
We present fully local versions of the minimally non-local nucleon-nucleon potentials constructed in a previous paper [M.\ Piarulli {\it et al.}, Phys.\ Rev.\ C {\bf 91}, 024003 (2…