Abstract
The magnetic form factors of H2,H3, and He3, deuteron photodisintegration cross sections at low energies, and deuteron threshold electrodisintegration cross sections at backward angles in a wide range of momentum transfers are calculated with the chiral two-nucleon (and three-nucleon) interactions including Δ intermediate states that have recently been constructed in configuration space. The A=3 wave functions are obtained from hyperspherical-harmonics solutions of the Schrödinger equation. The electromagnetic current includes one- and two-body terms, the latter induced by one- and two-pion exchange (OPE and TPE, respectively) mechanisms and contact interactions. The contributions associated with Δ intermediate states are only retained at the OPE level and are neglected in TPE loop (tree-level) corrections to two-body (three-body) current operators. Expressions for these currents are derived and regularized in configuration space for consistency with the interactions. The low-energy constants that enter the contact currents are determined by reproducing the magnetic moments of these few-nucleon systems. The predicted form factors and deuteron electrodisintegration cross section are in excellent agreement with experiment for momentum transfers up to 2-3fm-1. However, the experimental values for the deuteron photodisintegration cross section are consistently underestimated by theory, unless use is made of the Siegert form of the electric dipole transition operator. A complete analysis of the results is provided, including the clarification of the origin of the aforementioned discrepancy.
| Original language | English |
|---|---|
| Article number | 034005 |
| Journal | Physical Review C |
| Volume | 99 |
| Issue number | 3 |
| DOIs | |
| State | Published - Mar 21 2019 |
| Externally published | Yes |
Funding
One of the authors (R.S.) thanks the T-2 group in the Theoretical Division at LANL, and especially J. Carlson and S. Gandolfi, for the support and warm hospitality extended to him during a sabbatical visit in the fall 2018, when part of this research was completed. The support of the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under contracts DE-AC05-06OR23177 (R.S.) and DE-AC02-06CH11357 (A.L., M.P., S.C.P., and R.B.W.), and award DE-SC0010300 (A.B.), is gratefully acknowledged. The work of A.L., S.P., M.P., S.C.P., and R.B.W. has been further supported by the NUclear Computational Low-Energy Initiative (NUCLEI) SciDAC project. Computational resources provided by the National Energy Research Scientific Computing Center (NERSC) are also thankfully acknowledged.
| Funders | Funder number |
|---|---|
| NUCLEI | |
| NUclear Computational Low-Energy Initiative | |
| Office of Nuclear Physics | DE-SC0010300, DE-AC02-06CH11357, DE-AC05-06OR23177 |
| U.S. Department of Energy | |
| Office of Science |