We present a new method to calculate the total ion-ion interaction potential in terms of building blocks, which we refer to as “single-particle interaction potentials.” This allows also the composition of the separate contributions of neutrons and protons to the interaction potentials. The method is applied to nuclear collisions via the use of time-dependent Hartree-Fock theory.

We measured the lifetimes of the $2_{1,2}^{+}$ and $4_1^{+}$ states in ${}^{98}$Ru in order to reduce their uncertainties and resolve the discrepancies in the literature for the lifetime of the $4_1^{+}$ state. Coulomb excitation in inverse kinematics was used to populate excited states in ${}^{98}$Ru, and the recoil distance doppler shift (RDDS) method was employed using the nNew Yale plunger device (NYPD). This technique combined with inverse Coulomb excitation requires several corrections due to relativistic and deorientation effects but yields high precision lifetimes. The determined $B_{4/2}=B(4_1^{+}\to 2_1^{+})/B(2_1^{+}\to 0_1^{+})=1.86\left(16\right)$ agrees well with the vibrational limit. In order to analyze the data, a new method for the deorientation correction of RDDS data was developed using the perturbation of experimental angular correlations. The simultaneous measurement of deorientation and lifetime of a given state and its application are discussed. The method is suitable for radioactive beam experiments.

We investigate effects of consistent (conserving the number of degrees of freedom) and inconsistent pion-nucleon-isobar couplings on the isobar propagator in vacuum and in nuclear medium. Using the consistent coupling in conjunction with a convenient basis leads to significant simplification of the isobar vacuum and in-medium self-energy and dressed propagator compared to the case of inconsistent interaction. The higher-derivative nature of the consistent interaction requires a suitable compensation by an additional form-factor term or adjustment in the used cut-off values. This modification is straightforward to perform and assures that the physical observables connected to the spin-3/2 sector in vacuum and nuclear medium acquire values indistinguishable from the ones obtained by using an inconsistent coupling.

A preferred candidate for neutrinoless double-β decay, ${}^{150}$Nd, is present in natural neodymium at an abundance level of 5.64$\%$. However, neodymium could be activated by cosmic rays during the period it spends on the Earth's surface. Its activation by protons is therefore of interest when it comes to estimating the possible disturbance effects and increased background during neutrinoless double-β-decay experiments like Sudbury Neutrino Observatory plus liquid scintillator (SNO+). In most cases, we lack experimental data on proton-induced reactions on neodymium. Therefore, a measurement of cross sections has been performed for the formation of ${}^{141}$Pm, ${}^{143}$Pm, ${}^{144}$Pm, ${}^{146}$Pm, ${}^{148}$Pm, ${}^{148}$Pm${}^m$, ${}^{149}$Pm, ${}^{150}$Pm, ${}^{140}$Nd, ${}^{141}$Nd, ${}^{147}$Nd, ${}^{149}$Nd, ${}^{138}$Pr${}^m$, ${}^{139}$Pr, ${}^{142}$Pr, and ${}^{139}$Ce by 10–30 MeV protons. Oxidation-protected metal foil targets of natural isotopic abundance were irradiated by the usual stacked-foil technique on the external proton beam of the isochronous cyclotron U-120M at the Nuclear Physics Institute at Řež near Prague. Special attention was paid to the excitation functions of long-lived radionuclides. The measured data were compared with TENDL-2010 library data (talys code).

This paper reports results for directed flow $v_1$ and elliptic flow $v_2$ of charged particles in Cu $+$ Cu collisions at $\sqrt{s_{NN}}=22.4$ GeV at the Relativistic Heavy Ion Collider. The measurements are for the 0–60$\%$ most central collisions, using charged particles observed in the STAR detector. Our measurements extend to 22.4-GeV Cu $+$ Cu collisions the prior observation that $v_1$ is independent of the system size at 62.4 and 200 GeV and also extend the scaling of $v_1$ with $\eta /y_{\mathrm{beam}}$ to this system. The measured $v_2\left(p_T\right)$ in Cu $+$ Cu collisions is similar for $\sqrt{s_{NN}}$ throughout the range 22.4 to 200 GeV. We also report a comparison with results from transport model (ultrarelativistic quantum molecular dynamics and multiphase transport model) calculations. The model results do not agree quantitatively with the measured $v_1\left(\eta \right),v_2\left(p_T\right)$, and $v_2\left(\eta \right)$.

The structure of dynamically generated states in the chiral unitary approach is studied from a viewpoint of their compositeness. We analyze the properties of bound states, virtual states, and resonances in a single-channel chiral unitary approach, paying attention to the energy dependence of the chiral interaction. We define the compositeness of a bound state using the field renormalization constant which is given by the overlap of the bare state and the physical state in the nonrelativistic quantum mechanics, or by the residue of the bound state propagator in the relativistic field theory. The field renormalization constant enables one to define a normalized quantitative measure of compositeness of the bound state. Applying this scheme to the chiral unitary approach, we find that the bound state generated by the energy-independent interaction is always a purely composite particle, while the energy-dependent chiral interaction introduces the elementary component, depending on the value of the cutoff parameter. This feature agrees with the analysis of the effective interaction by changing the cutoff parameter. A purely composite bound state can be realized by the chiral interaction only when the bound state lies at the threshold or when the strength of the two-body attractive interaction is infinitely large. The natural renormalization scheme, introduced by the property of the loop function and the matching with the chiral low-energy theorem, is shown to generate a bound state which is dominated by the composite structure when the binding energy is small.

With a half-life of 81.1$$Myr, ${}^{244}$Pu could be both the heaviest and the shortest-lived nuclide present on Earth as a relic of the last supernova(e) that occurred before the formation of the Solar System. Hoffman et al. [Nature (London) 234, 132 (1971)] reported on the detection of this nuclide ($1.0\times {10}^{-18}$ g ${}^{244}$Pu/g) in the rare-earth mineral bastnäsite with the use of a mass spectrometer. Up to now these findings were never reassessed. We describe the search for primordial ${}^{244}$Pu in a sample of bastnäsite with the method of accelerator mass spectrometry (AMS). It was performed with a highly sensitive setup, identifying the ions by the determination of their time-of-flight and energy. Using AMS, the stripping to high charge states allows the suppression of any molecular interference. During our measurements we observed no event of ${}^{244}$Pu. Therefore, we can give an upper limit for the abundance of ${}^{244}$Pu in our sample of the mineral bastnäsite of 370 atoms per gram ($1.5\times {10}^{-19}$ g ${}^{244}$Pu/g). The concentration of ${}^{244}$Pu in our sample of bastnäsite is significantly lower than the previously determined value.

Lifetimes of the $2_1^{+}$ states in ${}^{66,68}$Ge were measured using the recoil distance Doppler shift method. Excited states in ${}^{66}$Ge and ${}^{68}$Ge were populated using the ${}^{58}$Ni(${}^{10}$B, $p$2$n$) and ${}^{58}$Ni(${}^{12}$C, 2$p$) reactions, respectively. Lifetimes were extracted from coincidence data using the differential decay curve method. The resulting $B$($E$2; $2_1^{+}\to 0_1^{+}$) transition strengths are compared with large-scale shell-model calculations.

In this Brief Report we extend the α-decay half-life calculation to the superheavy emitter region to verify whether these nuclei satisfy the recently observed systematics [D. N. Poenaru et al., Phys. Rev. C 83, 014601 (2011);C. Qi et al., Phys. Rev. C 80, 044326 (2009)]. To establish the systematics, we have used the α-cluster potential description, which was originally developed to study $\alpha$ decay in connection with nuclear energy level structure [B. Buck et al., Phys. Rev. C 51, 559 (1995)]. The quantum-mechanical tunneling calculation has been employed to obtain the half-lives, showing that with this treatment the systematics are well reproduced in the region of heavy nuclei. Finally, the half-life calculation has been extended to the superheavy emitters to verify whether the systematics can still be observed.

The phase structure of symmetric nuclear matter in the extended Nambu–Jona-Lasinio (ENJL) model at finite baryon chemical potential ${\mu }_{{}_B}$ and temperature $T$ is studied by means of the effective potential in the one-loop approximation. It is found that chiral symmetry gets restored at high nuclear density and a typical first-order phase transition between liquid and gas occurs at zero temperature, $T=0$, which weakens as $T$ grows and eventually ends up with a critical point at $T\lesssim 18$ MeV. This phase transition scenario is confirmed by investigating the evolution of the effective potential as a function of effective nucleon mass and the equation of state. The restoration of chiral symmetry gives a second-order phase transition in the region $0⩽T\lesssim 171$ MeV and a first-order transition in the region $T\gtrsim 171$ MeV.

Convoluted differential and total cross sections of inelastic $\nu$ scattering on ${}^{128,130}$Te isotopes are computed from the original cross sections calculated previously using the quasiparticle random-phase approximation. We adopt various spectral distributions for the neutrino energy spectra such as the common two-parameter Fermi-Dirac and power-law distributions appropriate to explore nuclear detector responses to supernova neutrino spectra. We also concentrate on the use of low-energy $\beta$-beam neutrinos, originating from boosted ${\beta }^{-}$-radioactive ${}^6$He ions, to decompose original supernova (anti)neutrino spectra that are subsequently employed to simulate total cross sections of the reactions ${}^{130}\mathrm{Te}{(\tilde{\nu },{\tilde{\nu }}^{\prime })}^{130}{\mathrm{Te}}^{*}$. The concrete nuclear regimes selected, ${}^{128,130}$Te, are contents of the multipurpose CUORE and COBRA rare event detectors. Our present investigation may provide useful information about the efficiency of the Te detector medium of the above experiments in their potential use in supernova neutrino searches.

Collective flows of protons and negative pions have been studied in ${}^2$H $+$ C, Ta and He $+$ C, Ta collisions at an energy of 3.4 GeV/nucleon. The data have been obtained by the 2-m Propane Bubble Chamber (PBC-500) at JINR. It is found that the directed flow of protons and π${}^{-}$ mesons characterized by $d\langle P_x\rangle /d\left(y\right)$ increases with increase of the mass numbers of colliding nucleus pairs; the elliptic proton flow points out of the reaction plane and also strengthens as the system mass increases; the negative pion directed flow is in the same reaction plane as the proton flow for the lighter (${}^2$H $+$ C, He $+$ C) systems and in the opposite direction for the heavier (${}^2$H $+$ Ta, He $+$ Ta) systems. In ${}^2$H $+$ C, He $+$ C, C $+$ C, C $+$ Ne, ${}^2$H $+$ Ta, He $+$ Ta, C $+$ Cu, and C $+$ Ta collisions, the linear dependence of directed and elliptic flow parameters from mass numbers of projectile and target nuclei, ($A_P$·$A_T$)${}^{1/2}$, is similar for protons while for π${}^{-}$mesons the dependence of directed flow parameters is stronger. The ultrarelativistic quantum molecular dynamical model (URQMD) enlarged by the statistical multifragmentation model (SMM) satisfactorily describes the obtained experimental results for all pairs of nuclei. The data for such asymmetric nuclear collisions are obtained, to the best of our knowledge, for the first time.

We study the Bose-Einstein condensation of fermionic pairs in the uniform neutron matter by using the concept of the off-diagonal long-range order of the two-body density matrix of the system. We derive explicit formulas for the condensate density ${\rho }_{\mathrm{con}}$ and the condensate fraction ${\rho }_{\mathrm{con}}/\rho$ in terms of the scaled pairing energy gap $\Delta /{\epsilon }_F$ where ${\epsilon }_F$ is the Fermi energy. We calculate the condensate fraction ${\rho }_{\mathrm{con}}/\rho$ as a function of the density $\rho$ by using previously obtained results for the pairing gap $\Delta$. We find the maximum condensate fraction ${({\rho }_{\mathrm{con}}/\rho )}_{\max }=0.42$ at the density $\rho =5.3\times {10}^{-4}$ fm${}^{-3}$, which corresponds to the Fermi wave number $k_F=0.25$ fm${}^{-1}$.

Half-life ($T_{1/2}$) and β-delayed neutron branching ($P_n$) values of 492(25) ms and 49(8)$\%$, 350(15) ms and 72(8)$\%$, and 93(13) ms and 90(10)$\%$ for the $r$-process nuclei ${}^{137,138,139}$Sb, respectively, have been measured at the CERN On-Line Isotope Mass Separator (ISOLDE) facility by counting β-delayed neutrons. More precise $T_{1/2}$ and $P_n$ values of 300(15) ms and 27(4)$\%$, and 273(7) ms and 50(8)$\%$ for ${}^{136,137}$Sn, respectively, have also been measured. The sources were prepared by using the selective ionization of Sb or Sn with the Resonance Ionization Laser Ion Source and the high-resolution mass separator. The new data for Sb isotopes are compared with calculated $T_{1/2}$ and $P_n$ values for both spherical and nonspherical shapes. The data have been incorporated into parametrized nucleosynthesis calculations of the $r$ process in high-entropy winds of core-collapse supernovae in order to study the properties of the $A$ $=$ 130 solar-system $r$-process abundance peak.

To develop a dinuclear system conception, dynamical deformation and nucleon transfer in the heavy ion fusion reaction process are viewed simultaneously as a diffusion process and are treated by solving a set of master equations with the variables of the quadrupole deformation of each nucleus and the mass asymmetry variable in the potential energy surface (PES) of the system. The PES is determined by these three variables (two deformation coordinates and the mass asymmetry coordinate) and further governs the variation of the three variables by the master equations. The nucleon transfer and dynamical deformations of nuclei are correlated in the reactions. So the energy surface of the system for nucleon transfer is dependent on deformations and, thus, is time dependent. The calculated results for the quasifission mass yields and the excitation function of the evaporation residue cross sections to form elements 114 and 116 are shown to be agreeable with the measured data.

The low-energy level structures of ${}_{25}^{64}$Mn${}_{39}$ and ${}_{25}^{66}$Mn${}_{41}$ were investigated through both the decay of Mn metastable states and the population of levels following the $\beta$ decay of ${}^{64}$Cr and ${}^{66}$Cr. The deduced level schemes and tentatively assigned spins and parities suggest the coexistence of spherical and deformed configurations above and below $N=40$ for the odd-odd Mn isotopes. The low-energy deformed configurations are attributed to the coupling between a proton in a $K=1/2^{-}$ level with neutrons in either the $K=1/2^{-}$ or the $K=3/2^{+}$ levels originating from the $\pi p_{3/2}$, $\nu p_{1/2}$, and $\nu g_{9/2}$ single-particle states, respectively.

The $2_2^{+}$ state in ${}^{132}$Te is identified as the one-phonon mixed-symmetry state in a projectile Coulomb excitation experiment presenting a firm example of a mixed-symmetry state in unstable, neutron-rich nuclei. The results of shell-model calculations based on the low-momentum interaction $V_{\mathrm{low}-k}$ are in good agreement with experiment demonstrating the ability of the effective shell-model interaction to produce states of mixed-symmetry character.

The fusion probability in “hot” fusion reactions leading to the synthesis of superheavy nuclei is investigated systematically. The quasifission barrier influences the formation of the superheavy nucleus around the “island of stability” in addition to the shell correction. Based on the quasifission barrier height obtained with the Skyrme energy-density functional, we propose an analytical expression for the description of the fusion probability, with which the measured evaporation residual cross sections can be reproduced acceptably well. Simultaneously, some special fusion reactions for synthesizing new elements 119 and 120 are studied. The predicted evaporation residual cross sections for ${}^{50}$Ti + ${}^{249}$Bk are $\sim$10–150 fb at energies around the entrance-channel Coulomb barrier. For the fusion reactions synthesizing element 120 with projectiles ${}^{54}$Cr and ${}^{58}$Fe, the cross sections fall to a few femtobarns, which seems beyond the limit of the available facilities.

The first observation of the prompt and the delayed $\gamma$ transitions involving the high spin states in ${}^{210}$Fr is reported. The decay of the high spin states and the isomeric levels of ${}^{210}$Fr, identified for the first time from the known sequence of low-lying transitions found earlier in the $\alpha$ decay of ${}^{214}$Ac, were studied. High spin states of the doubly-odd ${}^{210}$Fr, which were produced by the fusion evaporation reaction ${}^{197}$Au (${}^{16}$O, $xn$) ${}^{213-x}$Fr, were populated and the subsequent emitted $\gamma$ rays were detected through the high-sensitivity germanium clover detector array INGA. The level scheme up to yrast levels of 5.3 MeV excitation energy and $\sim 20\hslash$ angular momentum could be established for the first time through $\gamma \gamma$, $\gamma \gamma \Delta T$ coincidence, and DCO ratio measurements. A new low-lying isomeric transition at $E_{\gamma }=$ 203(2) keV was observed. The half-life was measured to be $T_{1/2}=$ 41(2) ns. The measured half-life was compared with the corresponding single-particle estimate, based on the level scheme obtained from the experiment.