Cross sections of the ${}^{10}\mathrm{B}(n,t2\alpha )$ three-body reaction were measured at $E_n=4.0$, 4.5, and 5.0 MeV using a twin gridded ionization chamber and a thin-film ${}^{10}\mathrm{B}$ sample. The present paper is the second part of the work. A digital data-acquisition system was developed for the gridded ionization chamber based on the waveform digitizer. A thin-film ${}^{10}\mathrm{B}$ sample was designed and prepared. The number of ${}^{10}\mathrm{B}$ atoms in the sample was determined by the relative method using the thermal neutron induced ${}^{10}\mathrm{B}(n_{th},\alpha ){}^7\mathrm{Li}$ and ${}^6\mathrm{Li}(n_{th},t){}^4\mathrm{He}$ reactions with a ${}^6\mathrm{LiF}$ sample as the reference. The measurement of the ${}^{10}\mathrm{B}(n,t2\alpha )$ reaction was performed at the 4.5 MV Van de Graaff accelerator of Peking University. In the measurement, the double-coincidence technique was used, which involves the forward-backward and the grid-anode coincidence. In the data processing, the effective event area in the forward two-dimensional spectrum and the time window in the drift-time spectrum were employed to reject the background events. Cross sections of the ${}^{10}\mathrm{B}(n,t2\alpha )$ and ${}^{10}\mathrm{B}(n,\alpha ){}^7\mathrm{Li}$ reactions were obtained. The present results are compared with the data of existing measurements and evaluations.

We present a covariant formulation and model calculations of the leading-twist time-reversal even transverse-momentum-dependent quark distribution functions (TMDs) for a spin-one target. Emphasis is placed on a description of these three-dimensional distribution functions which is independent of any constraints on the spin quantization axis. We apply our covariant spin description to all nine leading-twist time-reversal even $\rho$ meson TMDs in the framework provided by the Nambu–Jona-Lasinio model, incorporating important aspects of quark confinement via the infrared cutoff in the proper-time regularization scheme. In particular, the behaviors of the three-dimensional TMDs in a tensor polarized spin-one hadron are illustrated. Sum rules and positivity constraints are discussed in detail. Our results do not exhibit the familiar Gaussian behavior in the transverse momentum, and other results of interest include the finding that the tensor polarized TMDs—associated with spin-one hadrons—are very sensitive to quark orbital angular momentum, and that the TMDs associated with the quark operator ${\gamma }^{+}{\mathbf{\gamma }}_T{\gamma }_5$ would vanish were it not for dynamical chiral symmetry breaking. In addition, we find that 44% of the $\rho$ meson's spin is carried by the orbital angular momentum of the quarks, and that the magnitude of the tensor polarized quark distribution function is about 30% of the unpolarized quark distribution. A qualitative comparison between our results for the tensor structure of a quark-antiquark bound state is made to existing experimental and theoretical results for the two-nucleon (deuteron) bound state.

The one-quasiparticle random-phase approximation (one-QRPA) method is used to describe simultaneously both double-$\beta$-decay modes, giving special attention to the partial restoration of spin-isospin $\text{SU}\left(4\right)$ symmetry. To implement this restoration and to fix the model parameters, we resort to the energetics of Gamow-Teller resonances and to the minima of the single-${\beta }^{+}$-decay strengths. This makes the theory predictive regarding the $\beta {\beta }_{2\nu }$ decay, producing the $2\nu$ moments in ${}^{48}\mathrm{Ca}$, ${}^{76}\mathrm{Ge}$, ${}^{82}\mathrm{Se}$, ${}^{96}\mathrm{Zr}$, ${}^{100}\mathrm{Mo}$, ${}^{128,130}\mathrm{Te}$, and ${}^{150}\mathrm{Nd}$, that are of the same order of magnitude as the experimental ones; however, the agreement with $\beta {\beta }_{2\nu }$ data is only modest. To include contributions coming from induced nuclear weak currents, we extend the $\beta {\beta }_{0\nu }$-decay formalism employed previously in C. Barbero et al., Nucl. Phys. A 628, 170 (1998), which is based on the Fourier-Bessel expansion. The numerical results for the $\beta {\beta }_{0\nu }$ moments in the above mentioned nuclei are similar to those obtained in other theoretical studies although smaller on average by $\sim 40\%$. We attribute this difference basically to the one-QRPA method, employed here for the first time, instead of the currently used two-QRPA method. The difference is partially due also to the way of carrying out the restoration of the spin-isospin symmetry. It is hard to say which is the best way to make this restoration, since the $\beta {\beta }_{0\nu }$ moments are not experimentally measurable. The recipe proposed here is based on physically robust arguments. The numerical uncertainties in the $\beta \beta$ moments, related to (i) their strong dependence on the residual interaction in the particle-particle channel when evaluated within the QRPA, and (ii) lack of proper knowledge of single-particle energies, have been quantified. It is concluded that the partial restoration of the $\text{SU}\left(4\right)$ symmetry, generated by the residual interaction, is crucial in the description of the $\beta \beta$ decays, regardless of the nuclear model used.

We present the results of precision mass measurements of neutron-rich cadmium isotopes. These nuclei approach the $N=82$ closed neutron shell and are important to nuclear structure as they lie near doubly magic ${}^{132}\mathrm{Sn}$ on the chart of nuclides. Of particular note is the clear identification of the ground-state mass in ${}^{127}\mathrm{Cd}$ along with the isomeric state. We show that the ground state identified in a previous mass measurement which dominates the mass value in the Atomic Mass Evaluation is an isomeric state. In addition to ${}^{127/m}\mathrm{Cd}$, we present other cadmium masses measured (${}^{125/m}\mathrm{Cd}$ and ${}^{126}\mathrm{Cd}$) in a recent TITAN experiment at TRIUMF. Finally, we compare our measurements to new ab initio shell-model calculations and comment on the state of the field in the $N=82$ region.

Magnetic-dipole and electric-quadrupole moments for ${}^{65,67,69,75,79\text{–}82}\mathrm{Ga}$ are reported using the Collinear Resonance Ionization Spectroscopy (CRIS) technique at the ISOLDE facility, CERN. The moments of ${}^{65}\mathrm{Ga}$ have been measured for the first time: $\mu =+1.775\left(3\right){\mu }_{\mathrm{N}}$ and $Q_s=+21.0\left(15\right)e{\mathrm{fm}}^2$. These results are compared to shell-model calculations using the GXPF1 and JUN45 interactions and the trends of the moments approaching the region of the doubly magic ${}^{56}\mathrm{Ni}$ are discussed. Additionally, new values for the change in mean-square charge radii for ${}^{65}\mathrm{Ga}$ and ${}^{67}\mathrm{Ga}$ allow investigation into the odd-even staggering in the region below $N=40$.

The ${}^{153}\mathrm{Eu}\left(n,2n\right){}^{152}\mathrm{Eu}^{\mathrm{m}1,\mathrm{m}2,g}$ cross section was measured by means of the activation technique at three neutron energies in the range 13–15 MeV. The quasimonoenergetic neutron beam was formed via the ${}^3\mathrm{H}\left(d,n\right){}^4\mathrm{He}$ reaction, in the Pd-300 Neutron Generator at the Chinese Academy of Engineering Physics (CAEP). The activities induced in the reaction products were measured using high-resolution γ-ray spectroscopy. The cross section of the population of the second high-spin ($8^{-}$) isomeric state was measured along with the reaction cross section populating both the ground ($3^{-}$) and the first isomeric state ($0^{-}$). Cross sections were also evaluated theoretically using the numerical code TALYS-1.8, with different level density options at neutron energies varying from the reaction threshold to 20 MeV. Results are discussed and compared with the corresponding literature.

We have incorporated the spin-dependent nucleon-nucleon cross sections into a Boltzmann-Uehling-Uhlenbeck transport model for the first time, using the spin-singlet and spin-triplet nucleon-nucleon elastic scattering cross sections extracted from the phase-shift analyses of nucleon-nucleon scatterings in free space. We found that the spin splitting of the collective flows is not affected by the spin-dependent cross sections, justifying it as a good probe of the in-medium nuclear spin-orbit interaction. With the in-medium nuclear spin-orbit mean-field potential that leads to local spin polarization, we found that the spin-averaged observables, such as elliptic flows of free nucleons and light clusters, becomes smaller with the spin-dependent differential nucleon-nucleon scattering cross sections.

The quantitative extraction of quark-gluon plasma (QGP) properties from heavy-ion data, such as its specific shear viscosity $\eta /s$, typically requires comparison to viscous hydrodynamic or “hybrid” hydrodynamics + transport simulations. In either case, one has to convert the fluid to hadrons, yet without additional theory input the conversion is ambiguous for dissipative fluids. Here, shear viscous phase-space corrections calculated using linearized transport theory are applied in Cooper-Frye freeze-out to quantify the effects on anisotropic flow coefficients $v_n\left(p_T\right)$ at the energies available at both the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider. Expanding upon our previous flow harmonics studies [D. Molnar and Z. Wolff, Phys. Rev. C 95, 024903 (2017); Z. Wolff and D. Molnar, J. Phys.: Conf. Ser. 535, 012020 (2014)], we calculate pion and proton $v_2\left(p_T\right)$, $v_4\left(p_T\right)$, and $v_6\left(p_T\right)$, but here we incorporate a hadron gas that is chemically frozen below a temperature of 175 MeV and use hypersurfaces from realistic viscous hydrodynamic simulations. For additive quark model cross sections and relative phase-space corrections with $p^{3/2}$ momentum dependence rather than the quadratic Grad form, we find at moderately high transverse momentum noticeably higher $v_4\left(p_T\right)$ and $v_6\left(p_T\right)$ for protons than for pions. In addition, the value of $\eta /s$ deduced from elliptic flow data differs by nearly 50% from the value extracted using the naive “democratic Grad” form of freeze-out distributions. To facilitate the use of the self-consistent viscous corrections calculated here in hydrodynamic and hybrid calculations, we also present convenient parametrizations of the corrections for the various hadron species.

We compare phenomenological results from $3+1\mathrm{D}$ quasiparticle anisotropic hydrodynamics (aHydroQP) with experimental data collected in the CERN Large Hadron Collider 2.76 TeV Pb-Pb collisions. In particular, we present comparisons of particle spectra, average transverse momentum, elliptic flow, and Hanbury Brown–Twiss radii. The aHydroQP model relies on the introduction of a single temperature-dependent quasiparticle mass which is fit to lattice QCD data. By taking moments of the resulting Boltzmann equation, we obtain the dynamical equations used in the hydrodynamic stage which include the effects of both shear and bulk viscosities. At freeze-out, we use anisotropic Cooper-Frye freeze-out performed on a fixed-energy-density hypersurface to convert to hadrons. To model the production and decays of the hadrons we use therminator2 which is customized to sample from ellipsoidal momentum-space distribution functions. Using smooth Glauber initial conditions, we find very good agreement with many heavy-ion collision observables.

We propose the measurement of net $\mathrm{\Lambda }$ and $\overline{\mathrm{\Lambda }}$ helicity, correlated event by event with the magnitude and sign of charge separation along the event's magnetic field direction, as a probe to investigate the chiral magnetic effect (CME) in heavy-ion collisions. With a simple simulation model of heavy-ion events that includes effects of local parity violation, we estimate the experimental correlation signal that could be expected at RHIC given the results of previous measurements that are sensitive to the CME.

Background: While the $N=50$ shell-gap evolution towards ${}^{78}\mathrm{Ni}$ is presently in the focus of nuclear structure research, experimental information on the neutron effective single-particle energy sequence above the ${}^{78}\mathrm{Ni}$ core remain scarce. Direct nucleon-exchange reactions are indeed difficult with presently available post-accelerated radioactive-ion beams (especially for high orbital-momentum orbitals) in this exotic region.

Purpose: In this study we probe the evolution of the $\nu 1g_{7/2}$ effective single-particle energy which is a key to understanding the possible evolution of the spin-orbit splitting due to the proton-neutron interaction in the ${}^{78}\mathrm{Ni}$ region. To achieve this goal, a method based on lifetime measurements is used for the first time. The obtained lifetimes of the $7/2_1^{+}$ states in ${}^{87}\mathrm{Kr}$ and ${}^{85}\mathrm{Se}$ are used to investigate the $\nu 1g_{7/2}$ evolution.

Method: Yrast and near-yrast states in the light $N=51$ isotones ${}^{85}\mathrm{Se}$ and ${}^{87}\mathrm{Kr}$ were populated via multinucleon transfer reactions, using a ${}^{82}\mathrm{Se}$ beam and a ${}^{238}\mathrm{U}$ target at the LNL tandem-ALPI facility. The prompt $\gamma$ rays were detected by the AGATA Demonstrator and particle identification was performed using the PRISMA spectrometer. Lifetime measurements were performed by using the Cologne plunger device for deep inelastic reactions and the Recoil Distance Doppler Shift technique.

Results: We obtain ${\tau }_{(7/2_1^{+})}=0.4_{-0.4}^{+1.6}$ ps for ${}^{87}\mathrm{Kr}$. In the case of ${}^{85}\mathrm{Se}$ an upper limit of 3(2) ps is obtained for the ${\tau }_{7/2_1^{+}}$ value.

Conclusion: For ${}^{87}\mathrm{Kr}$, the measured $(7/2_1^{+})$ lifetime is consistent with a core-coupled $2^{+}\otimes \nu 2d_{5/2}$ configuration for this state. This result is consistent with that obtained by direct reaction, which validates our method. For ${}^{85}\mathrm{Se}$, the measured $7/2_1^{+}$ lifetime limit indicates a very small contribution of the $\nu 1g_{7/2}$ configuration to the wave function of this state.

Using high-precision Penning trap mass spectrometry at the Low Energy Beam and Ion Trap facility at the National Superconducting Cyclotron Laboratory we have measured the $Q$ values of the fourth-order forbidden $\beta$ decay and electron capture of ${}^{50}\mathrm{V}$ and the double electron capture $Q$ value of ${}^{50}\mathrm{Cr}$ with the results $Q_{\beta }\left({}^{50}\mathrm{V}\right)=1038.1\left(1\right)$ keV, $Q_{\mathrm{EC}}\left({}^{50}\mathrm{V}\right)=2208.7\left(1\right)$ keV, and $Q_{2\mathrm{EC}}\left({}^{50}\mathrm{Cr}\right)=1170.5\left(1\right)$ keV. In addition, we have measured the atomic masses of ${}^{46,47,49,50}\mathrm{Ti},{}^{50,51}\mathrm{V}$, and ${}^{50,52–54}\mathrm{Cr}$, reducing uncertainties by factors of up to three compared with the most recent atomic mass evaluation $\left(Ame2016\right)$ [Chin. Phys. C 41, 030003 (2017)]. Our results are in good agreement with $Ame2016$ for ${}^{46,47,49,50}\mathrm{Ti}$ and ${}^{50,54}\mathrm{Cr}$ and show deviations of up to $\sim 1\mathrm{keV}\left(2.5\sigma \right)$ for ${}^{50,51}\mathrm{V}$ and ${}^{50,54}\mathrm{Cr}$.

High-luminosity modern accelerators, like the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) and Large Hadron Collider (LHC) at European Organization for Nuclear Research (CERN), inherently have event pile-up scenarios which significantly contribute to physics events as a background. While state-of-the-art tracking algorithms and detector concepts take care of these event pile-up scenarios, several offline analytical techniques are used to remove such events from the physics analysis. It is still difficult to identify the remaining pile-up events in an event sample for physics analysis. Since the fraction of these events is significantly small, it may not be as serious of an issue for other analyses as it would be for an event-by-event analysis. Particularly when the characteristics of the multiplicity distribution are observable, one needs to be very careful. In the present work, we demonstrate how a small fraction of residual pile-up events can change the moments and their ratios of an event-by-event net-proton multiplicity distribution, which are sensitive to the dynamical fluctuations due to the QCD critical point. For this study, we assume that the individual event-by-event proton and antiproton multiplicity distributions follow Poisson, negative binomial, or binomial distributions. We observe a significant effect in cumulants and their ratios of net-proton multiplicity distributions due to pile-up events, particularly at lower energies. It might be crucial to estimate the fraction of pile-up events in the data sample while interpreting the experimental observable for the critical point.

We study the equation of state of QCD using an improved version of the three-flavor Polyakov–Nambu–Jona-Lasinio model beyond the mean-field approximation. It incorporates the effects of unquenched quarks into the Polyakov-loop effective potential, as well as mesonic contributions to the grand-canonical potential. We study in full detail the calculation of the thermodynamical potential in this approach and compare the resulting pressure and entropy density with the most-recent lattice-QCD calculations at zero baryochemical potential. Finally, we present some exploratory results at finite chemical potential which include the phase diagram of the model, the quark and meson masses, and finally, the thermodynamical pressure.

The nuclear shell-model calculations show a clear anticorrelation between the Gamow-Teller strength and the transition rate of the collective quadrupole excitation from the ground state in response to artificial changes of the spin-orbit splitting. The shell-model calculations in the $fp$ space demonstrate that changes of the spin-orbit coupling influence Gamow-Teller and quadrupole modes in the opposite way. This interrelation is discussed in terms of simple symmetry arguments.

The origin of the large $\alpha$-particle production cross sections in systems involving weakly bound ${}^7\mathrm{Li}$ projectiles has been investigated by measuring the cross sections of all possible fragment-capture as well as complete fusion using the particle-$\gamma$ coincidence, in-beam, and off-beam $\gamma$-ray counting techniques for the ${}^7\mathrm{Li}+{}^{93}\mathrm{Nb}$ system at near Coulomb barrier energies. Almost all of the inclusive $\alpha$-particle yield has been accounted for. While the $t$-capture mechanism is found to be dominant ($\sim 70\%$), compound nuclear evaporation and breakup processes contribute $\sim 15\%$ each to the inclusive $\alpha$-particle production in the measured energy range. Systematic behavior of the $t$ capture and inclusive $\alpha$ cross sections for reactions involving ${}^7\mathrm{Li}$ over a wide mass range is also reported.

The thermodynamical properties of a neutral vector boson gas in a constant magnetic field are studied starting from the spectrum given by Proca formalism. Bose-Einstein condensation (BEC) and magnetization are obtained in the limit of low temperature. In this limit, the condensation is reached not only by decreasing the temperature or augmenting the density but also by increasing the magnetic field. The magnetization turns out to be a positive quantity that increases with the field; under certain conditions self-magnetization is possible. The anisotropy in the pressures due to the axial symmetry imposed to the system by the magnetic field is also discussed. Astrophysical implications are commented.

Many radiative capture reactions of astrophysical interest occur at such low energies that their direct measurement is hardly possible. Until now the only indirect method, which was used to determine the astrophysical factor of the astrophysical radiative capture process, was the Coulomb dissociation. In this paper we address another indirect method, which can provide information about resonant radiative capture reactions at astrophysically relevant energies. This method can be considered an extension of the Trojan horse method for resonant radiative capture reactions. The idea of the suggested indirect method is to use the indirect reaction $A(a,s\gamma )F$ to obtain information about the radiative capture reaction $A(x,\gamma )F$, where $a=\left(sx\right)$ and $F=\left(xA\right)$. The main advantage of using the indirect reactions is the absence of the penetrability factor in the channel $x+A$, which suppresses the low-energy cross sections of the $A(x,\gamma )F$ reactions and does not allow one to measure these reactions at astrophysical energies. A general formalism to treat indirect resonant radiative capture reactions is developed when only a few intermediate states contribute and a statistical approach cannot be applied. The indirect method requires coincidence measurements of the triple differential cross section, which is a function of the photon scattering angle, energy, and the scattering angle of the outgoing spectator particle $s$. Angular dependence of the triple differential cross section at fixed scattering angle of the spectator $s$ is the angular $\gamma -s$ correlation function. Using indirect resonant radiative capture reactions, one can obtain information about important astrophysical resonant radiative capture reactions such as $(p,\gamma )$, $(\alpha ,\gamma )$, and $(n,\gamma )$ on stable and unstable isotopes. The indirect technique makes accessible low-lying resonances, which are close to the threshold, and even subthreshold bound states located at negative energies. In this paper, after developing the general formalism, we demonstrate the application of the indirect reaction ${}^{12}\mathrm{C}({}^6\mathrm{Li},d\gamma ){}^{16}\mathrm{O}$ proceeding through $1^{-}$ and $2^{+}$ subthreshold bound states and resonances to obtain the information about the ${}^{12}\mathrm{C}(\alpha ,\gamma ){}^{16}\mathrm{O}$ radiative capture at the astrophysically most effective energy 0.3 MeV, which is impossible using standard direct measurements. Feasibility of the suggested approach is discussed.

States in the astrophysically important ${}^{19}\mathrm{Ne}$ nucleus have been populated directly using the ${}^{15}\mathrm{O}(\alpha ,\alpha ){}^{15}\mathrm{O}$ reaction with a radioactive ${}^{15}\mathrm{O}$ beam. Due to the challenges involved, this represents the first such ${}^{15}\mathrm{O}$ measurement with high resolution and the first dedicated to exploring the cluster structure. This measurement comprises three experiments: the first to develop the ${}^{15}\mathrm{O}$ radioactive beam, the second the resonant scattering study, and the third to measure the precise energy loss of O ions in ${}^4\mathrm{He}$ to reduce systematic uncertainties. The results show evidence for ${}^{15}\mathrm{O}+\alpha$ cluster structure which could explain earlier results pointing to the increased $\alpha$ branching ratio in the astrophysical reaction rate for high-spin near-threshold resonances. Absolute differential cross sections have been measured. Additionally, spins, parities, and partial decay widths, essential for nuclear reaction-rate calculations, have been extracted using an $R$-matrix analysis.