Nuclear Theory·nucl-th

Wednesday·February 22, 2017

7 papers—4 primary·3 cross-listed

05
Re-examining valence quark spin distributions
A. I. Signal🇳🇿
The observed deep inelastic nucleon spin asymmetries $A_{1}^{p, n}$ and the spin dependent quark distributions break SU(6) spin - flavour symmetry. In quark models two mechanisms for breaking SU(6) symmetry are well known: the hyperfine interaction and the pion cloud of the nucleon. I re-evaluate these mechanisms and show how the breaking of SU(6) in each case affects spin dependent valence quark distributions of the proton. In particular I investigate the properties of these mechanisms in the kinematic region $0.3 < x < 0.7$ and attempt to test these against known data. Both mechanisms are able to explain the quantitative features of the spin asymmetries.
↳ hep-phnucl-thPRD(2017)·3 citations
06
Including resummation in the NLO BK equation
T. Lappi🇫🇮 · H. Mäntysaari🇺🇸
We include a resummation of large transverse momentum logarithms in the next-to-leading order (NLO) Balitsky-Kovchegov equation. The resummed evolution equation is shown to be stable, the evolution speed being significantly reduced by NLO corrections. The contributions from NLO terms that are not enhanced by large logarithms are found to be numerically important close to phenomenologically relevant initial conditions. We numerically determine the value for the constant in the resummed logarithm that includes a maximal part of the full NLO terms in the resummation.
↳ hep-phnucl-thNucl.Part.Phys.Proc.(2017)·0 citations
07
Universal behavior of few-boson systems using potential models
A. Kievsky🇮🇹 · M. Viviani🇮🇹 · R. Álvarez-Rodrí guez🇪🇸 · M. Gattobigio🇫🇷 · A. Deltuva🇱🇹
The universal behavior of a three-boson system close to the unitary limit is encoded in a simple dependence of many observables in terms of few parameters. For example the product of the three-body parameter $κ_{*}$ and the two-body scattering length $a$ , $κ_{*} a$ depends on the angle $ξ$ defined by $E_{3} / E_{2} = tan^{2} ξ$ . A similar dependence is observed in the ratio $a_{A D} / a$ with $a_{A D}$ the boson-dimer scattering length. We use a two-parameter potential to determine this simple behavior and, as an application, to compute $a_{A D}$ for the case of three $^{4}$ He atoms.
↳ cond-mat.quant-gasnucl-thFew Body Syst.(2017)·3 citations

Affiliations

first authorsco-authorsvia INSPIRE

Re-examining valence quark spin distributions

Including resummation in the NLO BK equation

Universal behavior of few-boson systems using potential models

Affiliations