The $A_y$ Puzzle and the Nuclear Force

Abstract

The nucleon-deuteron analyzing power $A_y$ in elastic nucleon-deuteron scattering poses a longstanding puzzle. At energies $E_{lab}$ below approximately 30 MeV $A_y$ cannot be described by any realistic NN force. The inclusion of existing three-nucleon forces does not improve the situation. Because of recent questions about the ${}^3{P}_J$ NN phases, we examine whether reasonable changes in the NN force can resolve the puzzle. In order to do this we investigate the effect on the ${}^3{P}_J$ waves produced by changes in different parts of the potential (viz., the central force, tensor force, etc.), as well as on the 2-body observables and on $A_y$. We find that it is not possible with reasonable changes in the NN potential to increase the 3-body $A_y$ and at the same time to keep the 2-body observables unchanged. We therefore conclude that the $A_y$ puzzle is likely to be solved by new three-nucleon forces, such as those of spin-orbit type, which have not yet been taken into account.

35 pages in REVTeX, 1 figure in postscript and 3 figures in PiCTeX

References in corpus (3)

• Nuclear Sizes and the Isotope Shift
• Electromagnetic Corrections to the One-Pion-Exchange Potential
• Can the magnetic moment contribution explain the A_y puzzle?

Cited by in corpus (32)

• Chiral Symmetry and Three-Nucleon Forces
• Polarization observables in p-d scattering below 30 MeV
• Improved Convergence in the Three-Nucleon System at Very Low Energies
• Evidence for a three-nucleon-force effect in proton-deuteron elastic scattering
• Chiral Three-Nucleon Forces from p-wave Pion Production
• Naive Dimensional Analysis for Three-Body Forces Without Pions
• The three- and four-nucleon systems from chiral effective field theory
• Higher Partial Waves in an Effective Field Theory Approach to nd Scattering
• Phenomenological spin-orbit three-body force
• Proton-${}^3$He elastic scattering at low energies
• Proton-Deuteron Elastic Scattering from 2.5 to 22.5 MeV
• Benchmark calculations for polarization observables in 3N scattering
• ${}^3\mathrm{He}$ and $pd$ Scattering to Next-to-Leading Order in Pionless Effective Field Theory
• Chiral NN model and Ay puzzle
• Charge-Dependence of the Nucleon-Nucleon Interaction
• Isospin symmetry breaking nucleon-nucleon potentials and nuclear structure
• Low-energy p-d Scattering: High Precision Data, Comparisons with Theory, and Phase-Shift Analyses
• Experimental and theoretical evidences for an intermediate $\sigma$-dressed dibaryon in the NN interaction
• Why is the three-nucleon force so odd?
• The one-pion-exchange three-nucleon force and the $A_y$ puzzle
• $nd$ Scattering and the $A_y$ Puzzle to Next-to-next-to-next-to-leading Order
• Proton-deuteron elastic scattering at low energies
• Scaling properties of the longitudinal and transversal asymmetries of the $\vec{n}\vec{d}$ total cross section
• Neutron-deuteron scattering cross-sections with chiral $NN$ interactions using wave-packet continuum discretization
• Analyzing power in nucleon-deuteron scattering and three-nucleon forces
• Short-range three-nucleon forces and low-energy constants
• Resonant relativistic corrections and the A_y problem
• Analyzing powers in $d(\vec{p},pp)n$ at intermediate and large scattering angles at $190$~MeV
• Towards high partial waves in lattice QCD with a dumbbell-like operator
• On contribution of three-body forces to $Nd$ interaction at intermediate energies
• Posterior predictive distributions of neutron-deuteron cross sections
• Transverse Asymmetry in Nucleon Deuteron Scattering in Pionless Effective Field Theory