7 papers
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 calc…
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 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…
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…
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…
The 3He(\vec n,p)3H parity-conserving asymmetry
M. Viviani, S. BaeÃler, L. Barrón-Palos +28
Recently, the nHe collaboration reported a measurement of the parity-violating (PV) proton directional asymmetry $A_{\mathrm {PV}} = (1.55\pm 0.97~\mathrm {(st\ at)} \pm 0.24~\…