Nuclear Theory·nucl-th

Friday·August 12, 2016

7 papers—6 primary·1 cross-listed

01
Properties of an $α$ particle in a Bohrium $270$ Nucleus under the Generalized Symmetric Woods-Saxon Potential
B.C. Lütfüoğlu · M. Erdogan
The energy eigenvalues and the wave functions of an $α$ particle in a Bohrium $270$ nucleus were calculated by solving Schrödinger equation for Generalized Symmetric Woods-Saxon potential. Using the energy spectrum by excluding and including the quasi-bound eigenvalues, entropy, internal energy, Helmholtz energy, and specific heat, as functions of reduced temperature were calculated. Stability and emission characteristics are interpreted in terms of the wave and thermodynamic functions. The kinetic energy of a decayed $α$ particle was calculated using the quasi-bound states, which is found close to the experimental value.
nucl-thSDU J.Nat.Appl.Sci.(2017)·0 citations
02
Can Ab Initio Theory Explain the Phenomenon of Parity Inversion in $^{11}$ Be?
Angelo Calci🇨🇦 · Petr Navrátil🇨🇦 · Robert Roth🇩🇪 · Jérémy Dohet-Eraly🇨🇦 · Sofia Quaglioni🇺🇸 · Guillaume Hupin🇫🇷
The weakly bound exotic $^{11}$ Be nucleus, famous for its ground-state parity inversion and distinct n+ $^{10}$ Be halo structure, is investigated from first principles using chiral two- and three-nucleon forces. An explicit treatment of continuum effects is found to be indispensable. We study the sensitivity of the $^{11}$ Be spectrum to the details of the three-nucleon force and demonstrate that only certain chiral interactions are capable of reproducing the parity inversion. With such interactions, the extremely large E1 transition between the bound states is reproduced. We compare our photodisintegration calculations to conflicting experimental data and predict a distinct dip around the $3/ 2_{1}^{-}$ resonance energy. Finally, we predict low-lying $3/ 2^{+}$ and $9/ 2^{+}$ resonances that are not or not sufficiently measured in experiments.
nucl-thnucl-exPRL(2016)·113 citations
03
Improved treatment of blocking effect at finite temperature
N. Quang Hung · N. Dinh Dang · L. T. Quynh Huong
The blocking effect caused by the odd particle on the pairing properties of systems with odd number of fermions at finite temperature interacting via the monopole pairing force is studied within several approximations. The results are compared with the predictions obtained by using the exact solutions of the pairing Hamiltonian. The comparison favors the approximation with the odd particle occupying the top level, which is the closest to the Fermi surface and whose occupation number decreases with increasing temperature.
nucl-thPRC(2016)·12 citations
04
Dynamical freeze-out criterion in a hydrodynamical description of Au + Au collisions at $s_{NN} = 200$ GeV and Pb + Pb collisions at $s_{NN} = 2760$ GeV
Saeed Ahmad · Hannu Holopainen🇩🇪 · Pasi Huovinen🇩🇪
In hydrodynamical modeling of ultrarelativistic heavy-ion collisions, the freeze-out is typically assumed to take place at a surface of constant temperature or energy density. A more physical approach is to assume that freeze-out takes place at a surface of constant Knudsen number. We evaluate the Knudsen number as a ratio of the expansion rate of the system to the pion scattering rate, and apply the constant Knudsen number freeze-out criterion to ideal hydrodynamical description of heavy-ion collisions at RHIC ( $s_{NN} = 200$ GeV) and the LHC ( $s_{NN} = 2760$ GeV) energies. We see that once the numerical values of freeze-out temperature and freeze-out Knudsen number are chosen to produce similar $p_{T}$ distributions, the elliptic and triangular anisotropies are similar too, in both event-by-event and averaged initial state calculations.
nucl-thhep-phnucl-exPRC(2017)·15 citations
05
Coherent gamma photon generation in a Bose-Einstein condensate of $^{135 m}$ Cs
Luca Marmugi · P. M. Walker · F. Renzoni
We have identified a mechanism of collective nuclear de-excitation in a Bose-Einstein condensate of $^{135}$ Cs atoms in their isomeric states, $^{135 m}$ Cs, suitable for the generation of coherent gamma photons. The process described here does not correspond to single-pass amplification, which cannot occur in atomic systems due to the large shift between absorption and emission lines, nor does it require the large densities associated to standard Dicke super-radiance. It thus overcome the limitations that have been hindering the generation of coherent gamma rays in many systems. Therefore, we propose an approach for generation of coherent gamma rays, which relies on a combination of well established techniques of nuclear and atomic physics, and can be realized with currently available technology.
nucl-thcond-mat.quant-gasphysics.atom-phPLB(2018)·12 citations
06
Toward establishing low-lying $Λ$ and $Σ$ hyperon resonances with the $K ˉ + d \to π + Y + N$ reaction
H. Kamano🇯🇵 · T.-S. H. Lee🇺🇸
A model for the $K ˉ d \to π Y N$ reactions with $Y = Λ, Σ$ is developed, aiming at establishing the low-lying $Λ$ and $Σ$ hyperon resonances through analyzing the forthcoming data from the J-PARC E31 experiment. The off-shell amplitudes generated from the dynamical coupled-channels (DCC) model, which was developed in Kamano et al. [Phys. Rev. C 90, 065204 (2014)], are used as input to the calculations of the elementary $K ˉ N \to K ˉ N$ and $K ˉ N \to π Y$ subprocesses in the $K ˉ d \to π Y N$ reactions. It is shown that the cross sections for the J-PARC E31 experiment with a rather high incoming- $K ˉ$ momentum, $∣ p_{K ˉ} ∣ = 1$ GeV, can be predicted reliably only when the input $K ˉ N \to K ˉ N$ amplitudes are generated from a $K ˉ N$ model, such as the DCC model used in this investigation, which describes the data of the $K ˉ N$ reactions at energies far beyond the $K ˉ N$ threshold. We find that the data of the threefold differential cross section $d σ / (d M_{π Σ} d Ω_{p_{n}})$ for the $K^{-} d \to π Σ n$ reaction below the $K ˉ N$ threshold can be used to test the predictions of the resonance poles associated with $Λ (1405)$ . We also find that the momentum dependence of the threefold differential cross sections for the $K^{-} d \to π^{-} Λ p$ reaction can be used to examine the existence of a low-lying $J^{P} = 1/ 2^{+}$ $Σ$ resonance with a pole mass $M_{R} = 1457 - i 39$ MeV, which was found from analyzing the $K^{-} p$ reaction data within the employed DCC model.
nucl-thhep-exhep-phnucl-exPRC(2016)·19 citations
07
Magnetic Moments of Octet Baryons in Hot and Dense Nuclear Matter
Harpreet Singh🇮🇳 · Arvind Kumar🇮🇳 · Harleen Dahiya🇮🇳
We have calculated the in-medium magnetic moments of octet baryons in the presence of hot and dense symmetric nuclear matter. Effective magnetic moments of baryons have been derived from medium modified quark masses within chiral SU(3) quark mean field model. Further, for better insight of medium modification of baryonic magnetic moments, we have considered the explicit contributions from the valence quarks, sea quarks as well as sea orbital angular momentum of sea quarks. These effects have been successful in giving the description of baryonic magnetic moments in vacuum. The magnetic moments of baryons are found to vary significantly as a function of density of nuclear medium.
↳ hep-phnucl-thCPC(2017)·22 citations

Affiliations

first authorsco-authorsvia INSPIRE

Properties of an α particle in a Bohrium 270 Nucleus under the Generalized Symmetric Woods-Saxon Potential

Can Ab Initio Theory Explain the Phenomenon of Parity Inversion in 11Be?

Improved treatment of blocking effect at finite temperature

Dynamical freeze-out criterion in a hydrodynamical description of Au + Au collisions at sNN​​=200 GeV and Pb + Pb collisions at sNN​​=2760 GeV

Coherent gamma photon generation in a Bose-Einstein condensate of 135mCs

Toward establishing low-lying Λ and Σ hyperon resonances with the Kˉ+d→π+Y+N reaction

Magnetic Moments of Octet Baryons in Hot and Dense Nuclear Matter

Affiliations

Properties of an $α$ particle in a Bohrium $270$ Nucleus under the Generalized Symmetric Woods-Saxon Potential

Can Ab Initio Theory Explain the Phenomenon of Parity Inversion in $^{11}$ Be?

Dynamical freeze-out criterion in a hydrodynamical description of Au + Au collisions at $s_{NN} = 200$ GeV and Pb + Pb collisions at $s_{NN} = 2760$ GeV

Coherent gamma photon generation in a Bose-Einstein condensate of $^{135 m}$ Cs

Toward establishing low-lying $Λ$ and $Σ$ hyperon resonances with the $K ˉ + d \to π + Y + N$ reaction