Nuclear Theory·nucl-th

Monday·May 7, 2018

5 papers—3 primary·2 cross-listed

01
Parametrization of cross sections for elementary hadronic collisions involving strange particles
J. Hirtz🇫🇷 · J.-C. David🇫🇷 · A. Boudard🇫🇷 · J. Cugnon🇧🇪 · S. Leray🇫🇷 · I. Leya🇨🇭 · D. Mancusi🇫🇷
The production of strange particles (kaons, hyperons) and hypernuclei in light charged particle induced reactions in the energy range of a few GeV (2-15 GeV) has become a topic of active research in several facilities (e.g., HypHI and PANDA at GSI and/or FAIR (Germany), JLab (USA), and JPARC (Japan)). This energy range represents the low-energy limit of the string models (degree of freedom: quark and gluon) or the high-energy limit of the so-called spallation models (degree of freedom: hadrons). A well known spallation model is INCL, the Liège intranuclear cascade model (combined with a de-excitation model to complete the reaction). INCL, known to give good results up to 2-3 GeV, was recently upgraded by the implementation of multiple pion emission to extend the energy range of applicability up to roughly 15 GeV. The next step, to account also for strange particle production, both for refining the high energy domain and making it usable when strangeness appears, requires the following main ingredients: i) the relevant elementary cross sections (production, scattering, and absorption) and ii) the characteristics of the associated final states. Some of those ingredients are already known and, sometimes, are already used in models of the same type (e.g., Bertini, GiBUU), but this paper aims at reviewing the situation by compiling, updating, and comparing the necessary elementary information which are independent of the model used.
nucl-thEur.Phys.J.Plus(2018)·19 citations
02
Spectral function for $D ˉ_{0}^{*}$ $(0^{+})$ meson in isospin asymmetric nuclear matter with chiral partner structure
Daiki Suenaga🇯🇵
We study a spectral function for $D ˉ_{0}^{*}$ $(0^{+})$ meson in symmetric and neutron-rich asymmetric nuclear matter from the viewpoint of the partial restoration of chiral symmetry. Nuclear matter is constructed by a parity doublet model with hidden local symmetry which can reproduce properties at normal nuclear matter density as well as those in the vacuum. $D ˉ$ mesons are introduced by the chiral partner structure. Our results show that a mass of $D ˉ$ ( $0^{-}$ ) meson increases while a mass of $D ˉ_{0}^{*}$ meson decreases at mean field level as we increase the baryon density, reflecting the partial restoration of chiral symmetry. In the spectral function for $D ˉ_{0}^{*}$ meson, we find a threshold enhancement is remarkably enhanced which indicates this peak is an appropriate probe to observe the partial restoration of chiral symmetry in nuclear matter. We also find a resonance of $D ˉ_{0}^{*}$ meson revives at higher density due to a narrowing of the phase space. In the spectral function in neutron-rich asymmetric nuclear matter, we observe the threshold enhancement in negatively-charged $D ˉ_{0}^{*}$ meson channel stands at higher energy and its height is more enhanced compared to neutral $D ˉ_{0}^{*}$ meson channel, due to the violation of isospin symmetry. On the other hand, the resonance of negatively-charged $D ˉ_{0}^{*}$ meson is slightly suppressed compared to the neutral one.
nucl-th6 citations
03
Hindered alpha decays of heaviest high-K isomers
P. Jachimowicz · M. Kowal · J. Skalski
To find candidates for long-lived high-K isomers in even-even Z=106-112 superheavy nuclei we study dominant alpha-decay channel of two- and four-quasi-particle configurations at a low excitation. Energies are calculated within the microscopic - macroscopic approach with the deformed Woods-Saxon potential. Configurations are fixed by a standard blocking procedure and their energy found by a subsequent minimization over deformations. Different excitation energies of a high-K configuration in parent and daughter nucleus seem particularly important for a hindrance of the alpha-decay. A strong hindrance is found for some four-quasi-particle states, particularly $K^{π} = 2 0^{+}$ and/or $1 9^{+}$ states in $^{264 - 270}$ Ds. Contrary to what was suggested in experimental papers, it is rather a proton configuration that leads to this strong hindrance. If not shortened by the electromagnetic decay, alpha half-lives of $\sim$ 1 s could open new possibilities for studies of chemical/atomic properties of related elements.
nucl-thPRC(2018)·11 citations

Affiliations

first authorsco-authorsvia INSPIRE

Parametrization of cross sections for elementary hadronic collisions involving strange particles

Spectral function for Dˉ0∗​ (0+) meson in isospin asymmetric nuclear matter with chiral partner structure

Hindered alpha decays of heaviest high-K isomers

Affiliations

Spectral function for $D ˉ_{0}^{*}$ $(0^{+})$ meson in isospin asymmetric nuclear matter with chiral partner structure