Nuclear Theory·nucl-th

Wednesday·March 4, 2015

3 papers—3 primary·0 cross-listed

01
$K ˉ + N \to K + Ξ$ reaction and $S = - 1$ hyperon resonances
Benjamin C. Jackson🇺🇸 · Yongseok Oh🇰🇷 · H. Haberzettl🇺🇸 · K. Nakayama🇺🇸
The $K ˉ + N \to K + Ξ$ reaction is studied for center-of-momentum energies ranging from threshold to 3 GeV in an effective Lagrangian approach that includes the hyperon $s$ - and $u$ -channel contributions as well as a phenomenological contact amplitude. The latter accounts for the rescattering term in the scattering equation and possible short-range dynamics not included explicitly in the model. Existing data are well reproduced and three above-the-threshold resonances were found to be required to describe the data, namely, the $Λ (1890)$ , $Σ (2030)$ , and $Σ (2250)$ . For the latter resonance we have assumed the spin-parity of $J^{P} = 5/ 2^{-}$ and a mass of 2265 MeV. The $Σ (2030)$ resonance is crucial in achieving a good reproduction of not only the measured total and differential cross sections, but also the recoil polarization asymmetry. More precise data are required before a more definitive statement can be made about the other two resonances, in particular, about the $Σ (2250)$ resonance that is introduced to describe a small bump structure observed in the total cross section of $K^{-} + p \to K^{+} + Ξ^{-}$ . The present analysis also reveals a peculiar behavior of the total cross section data in the threshold energy region in $K^{-} + p \to K^{+} + Ξ^{-}$ , where the $P$ - and $D$ -waves dominate instead of the usual $S$ -wave. Predictions for the target-recoil asymmetries of the $K ˉ + N \to K + Ξ$ reaction are also presented.
nucl-thhep-phPRC(2015)·48 citations
02
Candidates for Long Lived High-K Ground States in Superheavy Nuclei
P. Jachimowicz · M. Kowal · J. Skalski
On the basis of systematic calculations for 1364 heavy and superheavy nuclei, including odd-systems, we have found a few candidates for high-K ground states in superheavy nuclei. The macroscopic-microscopic model based on the deformed Woods-Saxon single particle potential which we use offers a reasonable description of SH systems, including known: nuclear masses, $Q_{α}$ -values, fission barriers, ground state deformations, super- and hyper-deformed minima in the heaviest nuclei. %For odd and odd-odd systems, both ways of including pairing correlations, % blocking and the quasi-particle method, have been applied. Exceptionally untypical high-K intruder contents of the g.s. found for some nuclei accompanied by a sizable excitation of the parent configuration in daughter suggest a dramatic hindrance of the $α$ -decay. Multidimensional hyper-cube configuration - constrained calculations of the Potential Energy Surfaces (PES's) for one especially promising candidate, $^{272}$ Mt, shows a $⋍$ 6 MeV increase in the fission barrier above the configuration- unconstrained barrier. There is a possibility, that one such high-K ground- or low-lying state may be the longest lived superheavy isotope.
nucl-thPRC(2015)·22 citations
03
Plane correlations in small colliding systems
Li Yan🇫🇷
I propose event-plane correlations as a test of collectivity in small colliding systems: In d-Au and $^{3}$ He-Au collisions, I predict a strong anti-correlation between elliptic and triangular flow, generated by the geometry of the light projectile. A significant anti-correlation is also predicted in central p-Pb collisions at the LHC, which is solely generated by fluctuations. Similar, but stronger correlation patterns are predicted in correlations involving dipolar flow.
nucl-thhep-phnucl-exPRC(2015)·7 citations

Affiliations

first authorsco-authorsvia INSPIRE

Kˉ+N→K+Ξ reaction and S=−1 hyperon resonances

Candidates for Long Lived High-K Ground States in Superheavy Nuclei

Plane correlations in small colliding systems

Affiliations

$K ˉ + N \to K + Ξ$ reaction and $S = - 1$ hyperon resonances