International Journal of Modern Physics E

Predictions made in Albacete et al. [Int. J. Mod. Phys. E 22 (2013) 1330007] prior to the LHC $p+$Pb run at $\sqrt{s_{NN}}=5$ TeV are compared to currently available data. Some predictions shown here have been updated by including the same experimental cuts as the data. Some additional predictions are also presented, especially for quarkonia, that were provided to the experiments before the data were made public but were too late for the original publication.

In this paper, the $({}^3\mathrm{\text{He}},d)$ reactions are revisited, with the goal of obtaining spectroscopic factors (SF) for the transition to the ground state of some residual nuclei, applying the distorted wave Born approximation (DWBA). The double-folding São Paulo Potential (SPP) was used to derive the distorted wave function in the entrance and exit channels. The derived SF are compared with the results of extensive shell model calculations showing a rather good agreement.

We study nuclear structure properties for various isotopes of Ytterbium (Yb), Hafnium(Hf), Tungsten(W), Osmium(Os), Platinum(Pt) and Mercury(Hg) in $Z$ = 70–80 drip-line region starting from $N=80$ to $N=170$ within the formalism of relativistic mean field (RMF) theory. The pairing correlation is taken care by using BCS approach. We compared our results with finite range droplet model(FRDM) and experimental data and found that the calculated results are in good agreement. Neutron shell closure is obtained at $N=82$ and $126$ in this region. We have also studied probable decay mechanisms of these elements.

In this work, we explore the possibility that the motion of the deuterium ions emitted from Coulomb cluster explosions is highly disordered enough to resemble thermalization. We analyze the process of nuclear fusion reactions driven by laser–cluster interactions in experiments conducted at the Texas Petawatt laser facility using a mixture of D₂+³He and CD₄+³He cluster targets. When clusters explode by Coulomb repulsion, the emission of the energetic ions is “nearly” isotropic. In the framework of cluster Coulomb explosions, we analyze the energy distributions of the ions using a Maxwell–Boltzmann (MB) distribution, a shifted MB distribution (sMB), and the energy distribution derived from a log-normal (LN) size distribution of clusters. We show that the first two distributions reproduce well the experimentally measured ion energy distributions and the number of fusions from d–d and d-³He reactions. The LN distribution is a good representation of the ion kinetic energy distribution well up to high momenta where the noise becomes dominant, but overestimates both the neutron and the proton yields. If the parameters of the LN distributions are chosen to reproduce the fusion yields correctly, the experimentally measured high energy ion spectrum is not well represented. We conclude that the ion kinetic energy distribution is highly disordered and practically not distinguishable from a thermalized one.

The level structure in neutron-rich ${}^{114}$Pd nucleus has been reinvestigated by measuring prompt $\gamma$ rays emitted in the spontaneous fission of ${}^{252}$Cf. A two-phonon $\gamma$-vibrational band built on the 1639.3keV level is observed, which confirms the previous suggestion from a $\beta$-decay experiment. Systematical comparison supports the assignment for a two-phonon $\gamma$-vibrational band in ${}^{114}$Pd. Triaxial projected shell model calculations for the multi-phonon $\gamma$ bands of ${}^{114}$Pd are in good agreement with the experimental data.

The effect of using a temperature dependent pairing term in back-shifted Fermi-gas (BSFG) formula of nuclear level density has been studied. We have used the mean order parameter formula of modified Ginzburg–Landau (MGL) theory as a simple possible choice for temperature dependency of the pairing term. The level density and heat capacity of ${}^{98}$Mo have been calculated with this formalism and compared with the experimental data. We observed good agreement between the heat capacity of this model and the experimental data.

In this paper, we studied chiral phase transitions in the Tsallis nonextensive statistics which has two parameters, the temperature $T$ and entropic parameter $q$. The linear sigma model was used in this study. The critical temperature, condensate, masses and energy density were calculated under the massless free particle approximation. The critical temperature decreases as $q$ increases. The condensate at $q>1$ is smaller than that at $q=1$. The sigma mass at $q>1$ is heavier than the mass at $q=1$ at high temperature, while the sigma mass at $q>1$ is lighter than the mass at $q=1$ at low temperature. The pion mass at $q>1$ is heavier than the mass at $q=1$. The energy density increases remarkably as $q$ increases. The $q$ dependence in the case of the $q$-expectation value is weaker than that in the case of the conventional expectation value with a Tsallis distribution. The parameter $q$ should be smaller than $4/3$ from energetic point of view. The validity of the Tsallis statistics can be determined by the difference in $q$ of the restriction for $5/4<q<4/3$ when the interaction is weak, because the parameter $q$ is smaller than $5/4$ in the case of the conventional expectation value with a Tsallis distribution.

Starting from the QCD Hamiltonian written in the canonical Coulomb gauge formalism, we developed a mapping onto an SO(4) representation which is suitable for the description of the QCD spectra at low energies. The mapping does not break the flavor symmetry and it preserves the singlet-colorless structure of the states. We present and discuss the structure of integer and half-integer-spin states with masses below 2 GeV. Finally, we extend the formalism in order to include particle–hole-like correlations in building excitations.

Coherent state approach (CSA) is applied to the interacting boson model (IBM) in the rotational region. States of the $N$ particle system are built up in a most general form as a function of the shape parameters $\beta$ and $\gamma$. The parameter $\chi$ occurring in the quadrupole operator which determines the degree of the $\gamma$-softness is taken to be varying with the boson number. The excitation energy equations are formed by using the moment of inertia of a rotating system which is obtained from the solution of the cranking problem. For each isotope, the deformation parameter is found by minimizing the ground state energy equation. The results are used to fit the experimental excitation energy spectrum and the electric quadrupole transition ratios of Yb isotopes. It is found that CSA works well to predict the energy of the states up to $L=10$. But the predictions about the electric quadrupole transitions are nearly $1.5$ times greater than the experimental data.

A systematic calculation of alpha decay half-lives of 347 nuclei is considered in the framework of the Wentzel–Kramers–Brillouin (WKB) approximation using two formulas. A recently proposed barrier penetration formula, with some modified parameters, is used first. Second, a new analytic barrier penetration formula is derived by taking into account the centrifugal potential. A good agreement with experimental data is achieved especially for spherical nuclei. The new formula reproduces experimental alpha decay half-lives with a satisfying accuracy especially for penetration energies much lower than the Coulomb barrier.

Isomeric yields ratios and energy differential cross-section of metastable state excitation in the ${}^{138}\mathrm{\text{Ce}}(\gamma ,n){}^{137m,g}\mathrm{\text{Ce}}$ reaction has been studied in the 10–22MeV end-point energy range of bremsstrahlung beams. Experimental data are compared with Hauser–Feshbach calculations performed with TALYS-1.6 statistical model code.

In this paper, the radial sensitivity of the elastic scattering cross-section for the ⁴He and ⁶He on ${}^{120}$Sn have been examined at energies near the Coulomb barrier. We also investigate the variation of the potential radius depending on the incident energy for the ${}^4\mathrm{\text{He}}+{}^{120}$Sn and ${}^6\mathrm{\text{He}}+{}^{120}$Sn systems. Especially, we have taken care of to stay within one family for ${}^4\mathrm{\text{He}}+{}^{120}$Sn elastic scattering, i.e., using $V_0$ real depth have not been changed by more than 20–30%.

This article has been retracted due to incorrect results. A notice of retraction is published in the International Journal of Modern Physics E Volume 26, Issue 12, 1793001 (2017).

This paper contains study of Bohr Hamiltonian considering time-dependent form of two important and famous nuclear potentials and harmonic oscillator. Dependence on time in interactions is considered in general form. In order to investigate this system, a powerful mathematical method has been employed, so-called Lewis–Riesenfeld dynamical invariant method. Appropriate dynamical invariant for considered system has been constructed. Then its eigen functions and the wave function are derived. At the end, we discussed about physical meaning of the results.

We have studied the $\alpha$-decay properties of superheavy nuclei (SHN) $Z=124$ in the range $282\le A\le 333$ using the Coulomb and proximity potential model for deformed nuclei (CPPMDN). The calculated $\alpha$ half-lives agree with the values computed using the Viola–Seaborg systematic, the universal curve of Poenaru et al. [Phys. Rev. C 83 (2011) 014601; 85 (2012) 034615] and the analytical formulas of Royer [J. Phys. G$,$ Nucl. Part. Phys. 26 (2000) 1149]. To identify the mode of decay of these isotopes, the spontaneous-fission half-lives were also evaluated using the semiempirical relation given by Xu et al. [Phys. Rev. C 78 (2008) 044329]. The calculated half-lives help to predict the possible isotopes of this superheavy element $Z=124$. As we could observe $\alpha$ chain consistently from the nuclei ${}^{288-312}$124, we have predicted that these nuclei could not be synthesized and detected experimentally via $\alpha$ decay as their decay half-lives are too small. The nuclei ${}^{313-318}$124 were found to have long half-lives and hence could be sufficient to detect them if synthesized in a laboratory.

In this paper, we discuss the structure of Gamow states as solutions of Lippmann–Schwinger equation. The Friedrichs model is used to demonstrate it, both analytically and by applying perturbation theory to the extended spectrum of the Hamiltonian. The method presented here may be relevant to the inclusion of resonances in discrete basis, without the need of numerical constructions to define Gamow states, as entities depending on the choice of integrals contours, or as states resulting from ad hoc discretizations of the continuum.