Nuclear Theory·nucl-th

Friday·September 21, 2018

5 papers—2 primary·3 cross-listed

03
[Submitted on 19 Sept 2018] (cross-list from hep-ph)
Bulk observables in the LHC 5.02 TeV Pb+Pb collisions within the integrated HydroKinetic Model
V. M. Shapoval🇺🇦 · Yu. M. Sinyukov🇺🇦
The paper is devoted to the description and prediction of various bulk observables in the Pb+Pb collisions at the LHC energy $s_{N N} = 5.02$ TeV within the integrated hydrokinetic model (iHKM). Sensitivity of the results to the choice of the appropriate model parameter values is also investigated. It is found that changing of the relaxation time and the rate of thermalization, which characterize the pre-thermal stage of the matter evolution, as well as switching to another equation of state at the hydrodynamic stage and the corresponding hadronization temperature, does not destroy the results, if simultaneously one provides an appropriate adjusting of the initial time for the superdense matter formation and related maximal initial energy density.
Comments:
17 pages, 13 figures
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1809.07400 [pdf]
PRC(2019)·17 citations
04
[Submitted on 20 Sept 2018] (cross-list from hep-ph)
New narrow nucleon resonances $N^{*} (1685)$ and $N^{*} (1726)$ within the chiral quark-soliton model
Ghil-Seok Yang🇰🇷 · Hyun-Chul Kim🇰🇷
We investigate the strong and radiative decay widths of the narrow nucleon resonances $N^{*} (1685)$ and $N^{*} (1726)$ within the framework of the SU(3) chiral quark-soliton model. All the relevant parameters are taken from those used to describe the properties of the baryon octet and decuplet in previous works. The masses of the antidecuplet nucleon and the eikosiheptaplet (27-plet) nucleon with spin 3/2 are determined respectively to be $(1690.2 \pm 10.5) MeV$ and $(1719.6 \pm 7.4) MeV$ . The decay width for $N^{*} (1685) \to η + N$ is found to be approximately three times larger than that for $N^{*} (1685) \to π + N$ . The width of the decay $N^{*} (1726) 3/ 2^{+} \to η + N$ is even about 31 times larger than that of $N^{*} (1726) 3/ 2^{+} \to π + N$ . The ratio of the radiative decays for $N^{*} (1685)$ is obtained to be $Γ_{n n^{*} (1685)} / Γ_{p p^{*} (1685)} = 8.62 \pm 3.45$ which explains very well the neutron anomaly. In contrast, we find $Γ_{p p^{*} (1726)} / Γ_{n n^{*} (1726)} = 3.72 \pm 0.64$ , which indicates that the production of $N^{*} (1726)$ is more likely to be observed in the proton channel. We also examined the decay modes of these narrow nucleon resonances with the strangeness hadrons involved.
Comments:
15 pages, 1 figure. Final version to appear in PTEP
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
arXiv:
1809.07489 [pdf]
PTEP(2019)·6 citations
05
[Submitted on 20 Sept 2018] (cross-list from hep-ph)
Pion constituent quarks couplings strong form factors: a dynamical approach
Fabio L. Braghin🇧🇷
Form factors for pions interactions with constituent quarks are investigated as the leading effective couplings obtained from a one loop background field method applied to a global color model. Two pion field definitions are considered and the resulting eleven form factors are expressed in terms of components of the quark and gluon propagators that compose only two momentum dependent functions. A momentum dependent Goldberger Treiman relation is also obtained as one of the ratios between the form factors. The resulting form factors with pion momenta up to 1.5 GeV are exhibited for different quark effective masses and two different non-perturbative gluon propagators and they present similar behavior to fittings of experimental data from nucleons form factors. The corresponding pseudoscalar averaged quadratic radii (a.q.r.) and correction to the axial a.q.r. are presented as functions of the sea quark effective mass, being equal respectively to the scalar and vector ones at the present level of calculation.
Comments:
25 pages, 12 figures, revised version, few punctual corrections in the text
Subjects:
High Energy Physics — Phenomenology (hep-ph); Nuclear Theory (nucl-th)
arXiv:
1809.07608 [pdf]
PRD(2019)·12 citations

Affiliations

first authorsco-authorsvia INSPIRE

Bulk observables in the LHC 5.02 TeV Pb+Pb collisions within the integrated HydroKinetic Model

New narrow nucleon resonances N∗(1685) and N∗(1726) within the chiral quark-soliton model

Pion constituent quarks couplings strong form factors: a dynamical approach

Affiliations

New narrow nucleon resonances $N^{} (1685)$ and $N^{} (1726)$ within the chiral quark-soliton model