Nuclear Theory·nucl-th

Tuesday·February 28, 2017

12 papers—6 primary·6 cross-listed

01
Three-particle correlations in relativistic heavy ion collisions in a multiphase transport model
Yifeng Sun🇺🇸 · Che Ming Ko🇺🇸
Using a multiphase transport model, we study three-particle mixed harmonic correlations in relativistic heavy ion collisions by considering the observable $C_{m, n, m + n} = ⟨ ⟨ cos (m ϕ_{1} + n ϕ_{2} - (m + n) ϕ_{3})⟩ ⟩$ , where $ϕ_{1, 2, 3}$ are azimuthal angles of all particle triplets. We find that except for $C_{123}$ , our results on the centrality dependence of $C_{112}$ , $C_{224}$ and $C_{235}$ as well as the relative pseudorapidity dependence of $C_{123}$ and $C_{224}$ in Au+Au collisions at $s =$ 200 GeV agree reasonable well with the experimental data from the STAR Collaboration. We discuss the implications of our results.
nucl-thPLB(2017)·4 citations
02
Fully coupled-channel complex scaling method for the $K^{-} pp$ system
Akinobu Doté🇯🇵 · Takashi Inoue🇯🇵 · Takayuki Myo🇯🇵
We have developed a fully coupled-channel complex scaling method (ccCSM) for the study of the most essential kaonic nucleus, $‘‘ K^{-} pp, "$ which is a resonant state of a $K ˉ N N$ - $π Σ N$ - $π Λ N$ coupled-channel system based on a theoretical viewpoint. By employing the ccCSM and imposing the correct boundary condition of resonance, the coupled-channel problem is completely solved using a phenomenological energy-independent potential. As a result of the ccCSM calculation of $‘‘ K^{-} pp, "$ in which all three channels are treated explicitly, we have obtained three-body resonance as a Gamow state. The resonance pole indicates that the binding energy of $‘‘ K^{-} pp "$ and the half value of its mesonic decay width are 51 MeV and 16 MeV, respectively. In the analysis of the resonant wave function obtained using the ccCSM, we clarify the spatial configuration and channel compositions of $‘‘ K^{-} pp ."$ Compared with past studies of single-channel calculations based on effective $K ˉ N$ potentials, the current study provides a guideline for the determination of the $K ˉ N$ energy to be used in effective potentials.
nucl-thnucl-exPRC(2017)·28 citations
03
Phenomenological extraction of two-photon exchange amplitudes from elastic electron-proton scattering cross section data
I. A. Qattan🇦🇪
In this work, I improve on and extend to low and high $Q^{2}$ values the extractions of the $ε$ dependence of the real parts of the two-photon exchange (TPE) amplitudes relative to the magnetic form factor, as well as the ratio $P_{l} / P_{l}^{B or n} (ε, Q^{2})$ by using world data on $σ_{R} (ε, Q^{2})$ with an emphasis on precise new data covering the low-momentum region which is sensitive to the large-scale structure of the nucleon. I provide simple parametrizations of the TPE amplitudes, along with an estimate of the fit uncertainties. The extracted TPE amplitudes are compared with previous phenomenological extractions and TPE calculations. The $P_{l} / P_{l}^{B or n}$ ratio is extracted by using the new parametrizations of the TPE amplitudes and compared to previous extractions, TPE calculations, and direct measurements at $Q^{2}$ = 2.50 (GeV/c) $^{2}$ . The extracted TPE amplitudes are on the few-percentage-points level and behave roughly linearly with increasing $Q^{2}$ where they become nonlinear at high $Q^{2}$ . Contrary to $Y_{M}$ , which is influenced mainly by elastic contributions, I find $Y_{E}$ to be influenced by inelastic contributions at large $Q^{2}$ values. While $Y_{E}$ and $Y_{3}$ differ in magnitude, they have opposite sign and tend to partially cancel each other. This suggests that the TPE correction to $σ_{R} (ε, Q^{2})$ is driven mainly by $Y_{M}$ and to a lesser extent by $Y_{3}$ in agreement with previous phenomenological extractions and hadronic TPE calculations.
nucl-thPRC(2017)·20 citations
04
Amplitude reconstruction from complete electroproduction experiments and truncated partial-wave expansions
L. Tiator · R. L. Workman · Y. Wunderlich · H. Haberzettl
We compare the methods of amplitude reconstruction, for a complete experiment and a truncated partial-wave analysis, applied to the electroproduction of pseudoscalar mesons. We give examples which show, in detail, how the amplitude reconstruction (observables measured at a single energy and angle) is related to a truncated partial-wave analysis (observables measured at a single energy and a number of angles). A connection is made to existing data.
nucl-thnucl-exPRC(2017)·22 citations
05
Effect of nuclear matter incompressibility on the 16O+208Pb system
O.N.Ghodsi · F.Torabi
To analyze the property of nuclear matter in the 16O+208Pb collision system, the internuclear potential of the fusion reaction is calculated by using the Skyrme forces associated with an extensive nuclear matter incompressibility K range in the semiclassical energy density formalism. Comparison of the experimental fusion cross sections and those obtained by using potentials derived from different forces with various K values shows that the incompressibility of nuclear matter changes during the fusion process at different bombarding energies. The results indicate that, as the energy increases, the nuclear matter becomes more incompressible.
nucl-thPRC(2016)·6 citations
06
The effect of deformation and vibration on the alpha decay half-life
O. N. Ghodsi · E. Gholami
In this work, we expand upon our previous study, the effect of surface vibrations (low-lying vibrational states) on the calculation of penetration probability in alpha decay of spherical isotopes [Phys.Rev.C91,034611(2015)]. To this aim, the Coulomb and proximity potential model, taking in to account the ground state deformations of the involved nuclei along with the surface vibrations in the daughter nucleus, is used to evaluate the alpha decay probability. The results are compared with those obtained by spherical potential barrier, which shows the dramatic effect of employing the ground state deformations in case of deformed nuclei. As well, including of surface vibrations give rise to an increase in the value of tunneling probability in better agreement with experimental data.
nucl-thPRC(2016)·4 citations

Affiliations

first authorsco-authorsvia INSPIRE

Three-particle correlations in relativistic heavy ion collisions in a multiphase transport model

Fully coupled-channel complex scaling method for the K−pp system

Phenomenological extraction of two-photon exchange amplitudes from elastic electron-proton scattering cross section data

Amplitude reconstruction from complete electroproduction experiments and truncated partial-wave expansions

Effect of nuclear matter incompressibility on the 16O+208Pb system

The effect of deformation and vibration on the alpha decay half-life

Affiliations

Fully coupled-channel complex scaling method for the $K^{-} pp$ system