We investigate the vector and axial-vector constants for hyperon semileptonic decays within a general framework of a chiral soliton model. All relevant parameters for the SU(3) baryon wave functions were unambiguously determined by using the experimental data on the masses of the baryon octet and the decuplet. Using then the existing experimental data on the magnetic moments of the baryon octet and the decay constants of hyperon semileptonic decays, we are able to determine all the hyperon semileptonic decay constants ${(f_2/f_1)}^{B_1\to B_2}$ and ${(g_1/f_1)}^{B_1\to B_2}$ of the baryon octet unequivocally. In addition, we also present the results of the axial-vector constants for the transitions from the baryon decuplet to the octet.

Shell-model calculations are performed for even-even, odd-mass, and doubly-odd nuclei of Sn, Sb, Te, I, Xe, Cs, and Ba isotopes around mass 130 using the single-particle space made up of valence nucleons occupying the $0g_{7/2},1d_{5/2},2s_{1/2},0h_{11/2}$, and $1d_{3/2}$ orbitals. The calculated energies and electromagnetic transitions are compared with the experimental data. In addition, several typical isomers in this region are investigated.

Background: Spurious zero-energy Nambu-Goldstone (NG) modes appear when the symmetry of a system is spontaneously broken. The Thouless-Valatin inertia, the collective inertia of the NG mode, contains important information concerning collective motion.

Purpose: To establish an efficient and precise method for deriving the collective inertia and the conjugate operator of a NG mode, I derive an expression for the response function in terms of the coordinate-momentum representation of the quasiparticle random-phase approximation which is valid even if a symmetry-restoring zero-energy mode is present.

Methods: I use the finite amplitude method for computing the response function of superfluid nuclei with the nuclear density functional theory.

Results: I derived analytically the collective inertia and the conjugate coordinate operator of the NG mode from the zero-energy linear response with the momentum operator of the NG mode. The formulation is tested in the cases of translational and pairing rotational modes. Illustrative calculations are performed for the neutron pairing rotation in Sn isotopes, the proton pairing rotation in $N=82$ isotones, and the neutron and proton pairing rotations around the ${}^{130}\mathrm{Xe}$ nucleus.

Conclusions: The proposed formulation allows us to compute the collective inertia of the NG mode precisely and efficiently. The conjugate coordinate operator can be utilized to remove spurious contributions to the strength distribution in the finite amplitude method.

A complete characterization of the structure of nuclei can be obtained by combining information arising from inelastic scattering, Coulomb excitation, and $\gamma$-decay, together with one- and two-particle transfer reactions. In this way it is possible to probe both the single-particle and collective components of the nuclear many-body wave function resulting from the coupling of these modes and, as a result, diagonalizing the low-energy Hamiltonian. We address the question of how accurately such a description can account for experimental observations in the case of superfluid nuclei. Our treatment goes beyond the traditional approach, in which these properties are calculated separately, and most often for systems near closed shells, based on perturbative approximations (weak coupling). It is concluded that renormalizing empirically and on equal footing bare single-particle and collective motion of open-shell nuclei in terms of self-energy (mass) and vertex corrections (screening), as well as particle-hole and pairing interactions through particle-vibration coupling (PVC), leads to a detailed, quantitative account of the data, constraining the possible values of the $k$ mass, of the ${}^1{S}_0$ bare $NN$ interaction, and of the PVC strengths within a rather narrow window.

For the first time, the tilted axis cranking covariant density functional theory with pairing correlations has been formulated and implemented in a fully self-consistent and microscopic way to investigate the evolution of the spin axis and the pairing effects in rotating triaxial nuclei. The measured energy spectrum and transition probabilities for the ${}^{135}\mathrm{Nd}$ yrast band are reproduced well without any ad hoc renormalization factors when pairing effects are taken into account. A transition from collective to chiral rotation has been demonstrated. It is found that pairing correlations introduce additional admixtures in the single-particle orbitals, and, thus, influence the structure of tilted axis rotating nuclei by reducing the magnitude of the proton and neutron angular momenta while merging their direction.

Background: Deuteron-induced reactions serve as surrogates for neutron capture into compound states. Although these reactions are of great applicability, no theoretical efforts have been invested in this direction over the last decade.

Purpose: The goal of this work is to establish on firm grounds a theory for deuteron-induced neutron-capture reactions. This includes formulating elastic and inelastic breakup in a consistent manner.

Method: We describe this process both in post- and prior-form distorted wave Born approximation following previous works and discuss the differences in the formulation. While the convergence issues arising in the post formulation can be overcome in the prior formulation, in this case one still needs to take into account additional terms due to nonorthogonality.

Results: We apply our method to the ${}^{93}\mathrm{Nb}(d,p)X$ at $E_d=15$ and 25 MeV and are able to obtain a good description of the data. We look at the various partial wave contributions, as well as elastic versus inelastic contributions. We also connect our formulation with transfer to neutron bound states.

Conclusions: Our calculations demonstrate that the nonorthogonality term arising in the prior formulation is significant and is at the heart of the long-standing controversy between the post and the prior formulations of the theory. We also show that the cross sections for these reactions are angular-momentum dependent and therefore the commonly used Weisskopf limit is inadequate. Finally, we make important predictions for the relative contributions of elastic breakup and nonelastic breakup and call for elastic-breakup measurements to further constrain our model.

The source radii previously extracted by the STAR Collaboration from the $p-\mathrm{\Lambda }\oplus \overline{p}-\overline{\mathrm{\Lambda }}$ and $\overline{p}-\mathrm{\Lambda }\oplus p-\overline{\mathrm{\Lambda }}$ correlation functions measured in 10% most central Au+Au collisions at top Relativistic Heavy Ion Collider (RHIC) energy, $\sqrt{s_{NN}}=200$ GeV, differ by a factor of 2. The probable reason for this is the neglect of residual correlation effect in the STAR analysis. In the present paper we analyze baryon correlation functions within the Lednický and Lyuboshitz analytical model, extended to effectively account for the residual correlation contribution. Different analytical approximations for such a contribution are considered. We also use the averaged source radii extracted from hydrokinetic model (HKM) simulations to fit the experimental data. In contrast to the STAR experimental study, the calculations in HKM show both $p\mathrm{\Lambda }$ and $p\overline{\mathrm{\Lambda }}$ radii to be quite close, as expected from theoretical considerations. Using the effective Gaussian parametrization of residual correlations we obtain a satisfactory fit to the measured baryon-antibaryon correlation function with the HKM source radius value 3.28 fm. The baryon-antibaryon spin-averaged strong interaction scattering length is also extracted from the fit to the experimental correlation function.

The charge-density difference between ${}^{206}\mathrm{Pb}$ and ${}^{205}\mathrm{Tl}$, measured by elastic electron scattering, offers a unique opportunity to look for effects of short-range correlations on a shell-model wave function of a single proton. The measured difference is very similar to the charge density due to a proton in a $3s_{1/2}$ orbit. If there is a potential whose $3s_{1/2}$ wave function yields the measured difference between the charge distributions, no effect of short-range correlations is evident. To check this point, we look for a potential whose $3s_{1/2}$ wave function yields the measured data. We developed a novel method to obtain the potential directly from the density and its first and second derivatives. Fits to parametrized potentials were also carried out. The $3s_{1/2}$ wave functions of the potentials determined here reproduce fairly well the experimental data within the quoted errors. To detect possible effects of two-body correlations on the $3s_{1/2}$ shell-model wave function, more accurate measurements are required.

The system of intermediate fissility ${}^{132}\mathrm{Ce}$ has been studied experimentally and theoretically to investigate the dissipation properties of nuclear matter. Cross sections of fusion-fission and evaporation-residue channels together with light charged particle multiplicities in both channels, their spectra, light charged particle-evaporation residue angular correlations, and mass-energy distribution of fission fragments have been measured. Theoretical analysis has been performed using a multidimensional stochastic approach coupled with a Hauser-Feshbach treatment of particle evaporation. The main conclusions are that the full one-body shape-dependent dissipation mechanism allows the reproduction of the full set of experimental data and that after a time ${\tau }_d=5\times {10}^{-21}$ s from the equilibrium configuration of the compound nucleus, fission decay can occur in a time that can span several orders of magnitude.

Background: Proton-nucleus collisions have been used as a intermediate baseline for the determination of cold-medium effects. They lie between proton-proton collisions in vacuum and nucleus-nucleus collisions which are expected to be dominated by hot-matter effects. Modifications of the quark densities in nuclei relative to those of the proton are well established, although those of the gluons in the nucleus are not well understood. The effect of these modifications on quarkonium production are studied in proton-lead collisions at the CERN Large Hadron Collider (LHC) at a center-of-mass energy of 5.02 TeV.

Purpose: The possibility of whether the LHC proton-lead data can be described by nuclear modifications of the parton densities, referred to as shadowing, alone is examined. The results are compared to the nuclear modification factor and to the forward-backward ratio, as a function of both transverse momentum, $p_T$, and rapidity, $y$.

Methods: The color evaporation model of quarkonium production is employed at next-to-leading order (NLO) in the total cross section and leading order in the transverse momentum dependence. The EPS09 NLO modifications are used as a standard of comparison. The effect of the proton parton density and the choice of shadowing parametrization on the $p_T$ and rapidity dependence of the result is studied. The consistency of the shadowing calculations at LO and NLO are checked. The size of the mass and scale uncertainties relative to the uncertainty on the shadowing parametrization is also investigated. Finally, whether the expected cold-matter effect in nucleus-nucleus collisions can be modeled as the product of proton-nucleus results at forward and backward rapidity is studied.

Results: The rapidity and $p_T$ dependence of the nuclear modification factor is found to be generally consistent with the NLO calculations in the color evaporation model. The forward-backward ratio is more difficult to describe with shadowing alone. The LO and NLO calculations are inconsistent for EPS09, while other available parametrizations are consistent. The mass and scale uncertainties on quarkonium production are larger than those of the nuclear parton densities.

Conclusions: While shadowing is consistent with the nuclear suppression factors within the uncertainties, it is not consistent with the measured forward-backward asymmetry, especially as a function of transverse momentum. Data from $p+p$ collisions at the same energy are needed.

The combined cross section for absorption and charge exchange interactions of positively charged pions with carbon nuclei for the momentum range 200 MeV/$c$ to 300 MeV/$c$ have been measured with the DUET experiment at TRIUMF. The uncertainty is reduced by nearly half compared with previous experiments. This result will be a valuable input to existing models to constrain pion interactions with nuclei.

A $\gamma$-ray spectroscopy study of excited states in ${}^{26}\mathrm{Si}$ has been performed by using the ${}^{24}\mathrm{Mg}{(}^3\mathrm{He},n)$ reaction at a beam energy of 10 MeV. In particular, states have been studied above the proton threshold relevant for burning in the ${}^{25}\mathrm{Al}(p,\gamma ){}^{26}\mathrm{Si}$ reaction in novae. This reaction influences the amount of ${}^{26}\mathrm{Al}$ injected into the interstellar medium by novae, which contributes to the overall flux of cosmic $\gamma$-ray emission from ${}^{26}\mathrm{Al}$ observed in satellite missions. The present results point strongly to the existence of a $0^{+}$ state at an excitation energy of 5890 keV lying within the Gamow burning window, which raises questions about the existence and properties of another, higher-lying state reported in previous experimental work. The existence of two such states within this excitation energy region cannot be understood within the framework of $sd$-shell-model calculations.

Two low-lying neutron-unbound excited states of ${}^{24}\mathrm{O}$, populated by proton-knockout reactions on ${}^{26}\mathrm{F}$, have been measured using the MoNA and LISA arrays in combination with the Sweeper Magnet at the Coupled Cyclotron Facility at the NSCL using invariant mass spectroscopy. The current measurement confirms the separate identity of two states with decay energies 0.51(5) MeV and 1.20(7) MeV, and provides support for theoretical model calculations, which predict a $2^{+}$ first excited state and a $1^{+}$ higher-energy state. The measured excitation energies for these states, 4.70(15) MeV for the $2^{+}$ level and 5.39(16) MeV for the $1^{+}$ level, are consistent with previous lower-resolution measurements, and are compared with five recent model predictions.

Background: The previously reported levels assigned to ${}^{151,152,153}\mathrm{Pr}$ have recently been called into question regarding their mass assignment.

Purpose: We clarify the above questioned level assignments by measuring $\gamma$ transitions tagged with $A$ and $Z$ in an in-beam experiment in addition to the measurements from ${}^{252}\mathrm{Cf}$ spontaneous fission (SF) and establish new spectroscopic information from $N=84$ to $N=94$ in the Pr isotopic chain.

Methods: The isotopic chain ${}^{143–153}\mathrm{Pr}$ has been studied from the spontaneous fission of ${}^{252}\mathrm{Cf}$ by using Gammasphere and also from the measurement of the prompt $\gamma$ rays in coincidence with isotopically identified fission fragments using VAMOS++ and EXOGAM at Grand Accelerateur National d'Ions Lourds (GANIL). The latter were produced using ${}^{238}\mathrm{U}$ beams on a ${}^9\mathrm{Be}$ target at energies around the Coulomb barrier. The $\gamma \text{−}\gamma \text{−}\gamma \text{−}\gamma$ data from ${}^{252}\mathrm{Cf}$ (SF) and those from the GANIL in-beam $A$- and $Z$-gated spectra were combined to unambiguously assign the various transitions and levels in ${}^{151,152,153}\mathrm{Pr}$ and other isotopes.

Results: A band of 3 new transitions added to the known level in ${}^{145}\mathrm{Pr}$, 9 new transitions in two new bands in ${}^{147}\mathrm{Pr}$, 6 new transitions in a new level scheme for ${}^{148}\mathrm{Pr}$, two new bands with 17 new transitions in ${}^{149}\mathrm{Pr}$, and two new bands with 11 new transitions in ${}^{150}\mathrm{Pr}$ were identified by using $\gamma \text{−}\gamma \text{−}\gamma$ and $\gamma \text{−}\gamma \text{−}\gamma \text{−}\gamma$ coincidences and $A$ and $Z$-gated $\gamma \text{−}\gamma$ spectra. The transitions and levels previously assigned to ${}^{151,153}\mathrm{Pr}$ have been confirmed by the $\left(A,Z\right)$-gated spectra. Small changes have been made to their original level schemes. The transitions previously assigned to ${}^{152}\mathrm{Pr}$ are now assigned to ${}^{151}\mathrm{Pr}$ on the basis of the $\left(A,Z\right)$-gated spectra. Two new bands with 20 new transitions in ${}^{152}\mathrm{Pr}$ and one new band with 7 new transitions in ${}^{153}\mathrm{Pr}$ are identified from the $\gamma \text{−}\gamma \text{−}\gamma \text{−}\gamma$ coincidence spectra and the $\left(A,Z\right)$-gated spectrum. In addition, new $\gamma$ rays are also reported in ${}^{143–146}\mathrm{Pr}$.

Conclusions: New levels of ${}^{145,147–153}\mathrm{Pr}$ have been established, reliable mass assignments of the levels in ${}^{151,152,153}\mathrm{Pr}$ have been given in the present work, and new transitions have been identified in ${}^{143–146}\mathrm{Pr}$ showing the new avenues that are opened by combining the two experimental approaches.

Exploring nucleon drip lines and astrophysical rapid neutron capture process (r-process) paths in the nuclear landscape is extremely challenging in nuclear physics and astrophysics. While various models predict a similar proton drip line, their predictions for the neutron drip line and the r-process paths involving heavy neutron-rich nuclei exhibit a significant variation which hampers our accurate understanding of the r-process nucleosynthesis mechanism. By using microscopic density functional theory with a representative set of nonrelativistic and relativistic interactions, we demonstrate for the first time that this variation is mainly due to the uncertainty of nuclear matter symmetry energy $E_{\mathrm{sym}}\left({\rho }_{\mathrm{sc}}\right)$ at the subsaturation cross density ${\rho }_{\mathrm{sc}}=0.11/0.16\times {\rho }_0$ $({\rho }_0$ is saturation density), which reflects the symmetry energy of heavy nuclei. By using the recent accurate constraint on $E_{\mathrm{sym}}\left({\rho }_{\mathrm{sc}}\right)$ from the binding-energy difference of heavy-isotope pairs, we obtain quite precise predictions for the location of the neutron drip line, the r-process paths, and the number of bound nuclei in the nuclear landscape. Our results have important implications on extrapolating the properties of unknown neutron-rich rare isotopes from the data on known nuclei.

For the first time, using a unique finite-range interaction (D1M Gogny force), a fully coherent and time-feasible calculation of the Bohr Hamiltonian vibrational mass is envisioned in a Hartree-Fock-Bogoliubov + quasiparticle random-phase approximation (QRPA) framework. In order to reach a reasonable computation time, we evaluate the feasibility of this method by considering two restrictions for the QRPA: the Tamm-Dancoff approximation and the insertion of a valence space. We validate our approach in the even-even tin isotopes by comparing the convergence scheme of the mass parameter with those of built-in QRPA outputs: excited-state energy and reduced transition probability. The seeming convergence of these intrinsic quantities is shown to be misleading and the difference with the theoretical expected value is quantified. This work is a primary step towards the systematic calculation of mass parameters.

Irradiations of ${}^{239}\mathrm{Pu}$ and ${}^{240}\mathrm{Pu}$ targets with ${}^{48}\mathrm{Ca}$ beams aimed at the synthesis of $Z=114$ flerovium isotopes were performed at the Dubna Gas Filled Recoil Separator. A new spontaneously fissioning (SF) isotope ${}^{284}\mathrm{Fl}$ was produced for the first time in the ${}^{240}\mathrm{Pu}+{}^{48}\mathrm{Ca}$ (250 MeV) and ${}^{239}\mathrm{Pu}+{}^{48}\mathrm{Ca}$ (245 MeV) reactions. The cross section of the ${}^{239}\mathrm{Pu}({}^{48}\mathrm{Ca},3n){}^{284}\mathrm{Fl}$ reaction channel was about 20 times lower than predicted by theoretical models and about 50 times lower than the maximum fusion-evaporation cross section for the $3n$ and $4n$ channels measured in the ${}^{244}\mathrm{Pu}+{}^{48}\mathrm{Ca}$ reaction. In the ${}^{240}\mathrm{Pu}+{}^{48}\mathrm{Ca}$ experiment, performed at 245 MeV in order to maximize the $3n$-evaporation channel, three decay chains of ${}^{285}\mathrm{Fl}$ were detected. The $\alpha$-decay energy of ${}^{285}\mathrm{Fl}$ was measured for the first time and decay properties of its descendants ${}^{281}\mathrm{Cn}, {}^{277}\mathrm{Ds}, {}^{273}\mathrm{Hs}, {}^{269}\mathrm{Sg}$, and ${}^{265}\mathrm{Rf}$ were determined with higher accuracy. The assignment of SF events observed during the irradiation of the ${}^{240}\mathrm{Pu}$ target with a 250 MeV ${}^{48}\mathrm{Ca}$ beam to ${}^{284}\mathrm{Fl}$ decay is presented and discussed. The cross sections at both ${}^{48}\mathrm{Ca}$ energies are similar and exceed that observed in the reaction with the lighter isotope ${}^{239}\mathrm{Pu}$ by a factor of 10. The decay properties of the synthesized nuclei and their production cross sections indicate a rapid decrease of stability of superheavy nuclei as the neutron number decreases from the predicted magic neutron number $N=184$.

Analysis and interpretation of spectrum and correlation data from high-energy nuclear collisions is currently controversial because two opposing physics narratives derive contradictory implications from the same data, one narrative claiming collision dynamics is dominated by dijet production and projectile-nucleon fragmentation, the other claiming collision dynamics is dominated by a dense, flowing QCD medium. Opposing interpretations seem to be supported by alternative data models, and current model-comparison schemes are unable to distinguish between them. There is clearly need for a convincing new methodology to break the deadlock. In this study we introduce Bayesian inference (BI) methods applied to angular correlation data as a basis to evaluate competing data models. For simplicity the data considered are projections of two-dimensional (2D) angular correlations onto a 1D azimuth from three centrality classes of 200-GeV Au-Au collisions. We consider several data models typical of current model choices, including Fourier series (FS) and a Gaussian plus various combinations of individual cosine components. We evaluate model performance with BI methods and with power-spectrum analysis. We find that FS-only models are rejected in all cases by Bayesian analysis, which always prefers a Gaussian. A cylindrical quadrupole $cos\left(2\varphi \right)$ is required in some cases but rejected for 0%–5%-central Au-Au collisions. Given a Gaussian centered at the azimuth origin, “higher harmonics” $cos\left(m\varphi \right)$ for $m>2$ are rejected. A model consisting of $\mathrm{Gaussian}+\mathrm{dipole}cos\left(\varphi \right)+\mathrm{quadrupole}cos\left(2\varphi \right)$ provides good 1D data descriptions in all cases.

We have performed for the first time a comprehensive study of the sensitivity of $r$-process nucleosynthesis to individual nuclear masses across the chart of nuclides. Using the latest version (2012) of the Finite-Range Droplet Model, we consider mass variations of $\pm 0.5$ MeV and propagate each mass change to all affected quantities, including $Q$ values, reaction rates, and branching ratios. We find such mass variations can result in up to an order of magnitude local change in the final abundance pattern produced in an $r$-process simulation. We identify key nuclei whose masses have a substantial impact on abundance predictions for hot, cold, and neutron star merger $r$-process scenarios and could be measured at future radioactive beam facilities.

Background: The Doppler broadening of $\gamma$-ray peaks due to nuclear recoil from $\beta$-delayed nucleon emission can be used to measure the energies of the nucleons. This method has never been tested using $\beta$-delayed proton emission or applied to a recoil heavier than $A=10$.

Purpose: To test and apply this Doppler broadening method using $\gamma$-ray peaks from the ${}^{26}\mathrm{P}\left(\beta p\gamma \right){}^{25}\mathrm{Al}$ decay sequence.

Methods: A fast beam of ${}^{26}\mathrm{P}$ was implanted into a planar Ge detector, which was used as a ${}^{26}\mathrm{P} \beta$-decay trigger. The SeGA array of high-purity Ge detectors was used to detect $\gamma$ rays from the ${}^{26}\mathrm{P}\left(\beta p\gamma \right){}^{25}\mathrm{Al}$ decay sequence.

Results: Radiative Doppler broadening in $\beta$-delayed proton-$\gamma$ decay was observed for the first time. The Doppler broadening analysis method was verified using the 1613-keV $\gamma$-ray line for which the proton energies were previously known. The 1776-keV $\gamma$ ray de-exciting the 2720 keV ${}^{25}\mathrm{Al}$ level was observed in ${}^{26}\mathrm{P}\left(\beta p\gamma \right){}^{25}\mathrm{Al}$ decay for the first time and used to determine that the center-of-mass energy of the proton emission feeding the 2720-keV level is $5.1\pm 1.0$ (stat.) $\pm 0.6$ (syst.) MeV, corresponding to a ${}^{26}\mathrm{Si}$ excitation energy of $13.3\pm 1.0$ (stat.) $\pm 0.6$ (syst.) MeV for the proton-emitting level.

Conclusions: The Doppler broadening method has been demonstrated to provide practical measurements of the energies for $\beta$-delayed nucleon emissions populating excited states of nuclear recoils at least as heavy as $A=25$.