We study the production of spin-one mesons in high-energy heavy-ion collisions with peripheral kinematics in the framework of quantum electrodynamics (QED). The cross sections of the production of a single vector meson and of two different ones are presented. The explicit dependence on the virtuality of the intermediate vector meson is obtained within a quark model. The effect of Reggeization of the intermediate vector-meson state in the case of the production of two vector mesons is taken into account.

The highly-efficient and segmented TIGRESS $\gamma$-ray spectrometer at TRIUMF has been used to perform a reorientation-effect Coulomb-excitation study of the 2${}_1^{+}$ state at 3.368 MeV in ${}^{10}$Be. This is the first Coulomb-excitation measurement that enables one to obtain information on diagonal matrix elements for such a high-lying first excited state from $\gamma$-ray data. With the availability of accurate lifetime data, a value of $-0.110\pm 0.087$ $e$b is determined for the $\langle 2_1^{+}\parallel \widehat{E2}\parallel 2_1^{+}\rangle$ diagonal matrix element, which assuming the rotor model, leads to a negative spectroscopic quadrupole moment of $Q_{{}_S}\left(2_1^{+}\right)=-0.083\pm 0.066$ $e$b. This result is in agreement with both no-core shell-model calculations performed in this work with the CD-Bonn 2000 two-nucleon potential and large shell-model spaces, and Green's function Monte Carlo predictions with two- plus three-nucleon potentials.

We apply the dimensional regularization procedure to treat an ultraviolet divergence occurring in the framework of the nuclear many-body problem. We consider the second-order correction (beyond the mean-field approximation) to the equation of state of nuclear matter with a zero-range effective interaction. The unphysical ultraviolet divergence that is generated at second order by the zero range of the interaction is removed by the regularization technique and the regularized equation of state ($\text{mean-field}+\text{second-order}$ contributions) is adjusted to a reference equation of state. The main practical advantage of this procedure, with respect to a cutoff regularization, is to provide a unique set of parameters for the adjusted effective interaction. This occurs because the regularized second-order correction does not contain any cutoff dependence. The encouraging results found in this work indicate that such an elegant technique to generate regularized effective interactions is likely to be applied in the future to finite nuclei in the framework of beyond-mean-field models.

Background: The symmetry-guided methods have shown their power over many years of nuclear physics research. It was found that the concept of the pseudospin symmetry is very helpful in providing a simple explanation of many features of heavy nuclei.

Purpose: To show, based on the results of calculations of the energies of the $\gamma$-vibrational states in nuclei with $Z\sim 100$, that the experimental data on these energies will give us information indicating how well the pseudospin symmetry is realized in these exotic nuclei.

Method: The quasiparticle-phonon model is used to calculate the energies of the $\gamma$-vibrational states.

Results: It is shown that the energies of the $\gamma$-vibrational states in the Cm, Cf, Fm, No, and Rf isotopes considered as the functions of the number of neutrons $N$ have a minimum at $N=156$ when the neutron Fermi level lies just between the following neutron single particle levels: 3/2[622] and 1/2[620] which belong to the pseudospin doublet. It is shown that the corresponding two-quasiparticle component gives the main contribution to the structure of the $\gamma$ phonon.

Conclusion: The experimental information on the energies of the $\gamma$-vibrational states in nuclei with $Z\sim 100$ can be used to determine a splitting of the $\widetilde{\left[521\right]}$ pseudospin doublet.

High-spin states in ${}^{138}$Nd were investigated using the reaction ${}^{94}$Zr(${}^{48}\mathrm{Ca},4n$), detecting coincident $\gamma$ rays with the gasp spectrometer. A rich level scheme was constructed including four bands of negative parity at low spins, eight bands of dipole transitions, and eight bands of quadrupole transitions at medium spins. The cranked shell model and the tilted-axis cranking model are used to assign configurations to the observed bands, where zero pairing is assumed. For selected configurations the case of finite pairing is also considered. A consistent notation for configuration assignment that applies for both zero and finite pairing is introduced. The observed bands are interpreted as rotation around the short and long principal axes (quadrupole bands), as well as around a tilted axis (dipole bands). The dipole bands have an intermediate character, between magnetic and collective electric rotation. A pair of dipole bands is identified as candidates for chiral partners. The possible existence of the wobbling mode at low deformation and medium spins is discussed. The consistent interpretation of the multitude of observed bands strongly supports the existence of stable triaxial deformation at medium spins in ${}^{138}$Nd.

Nuclear responses to energy spectra of supernova (SN) neutrinos are studied by folding original $\nu$-nucleus cross sections calculated in the context of the quasiparticle random-phase approximation using realistic two-body forces. To this purpose, we employ two-parameter neutrino-energy distributions of Fermi-Dirac and power-law shapes for various SN neutrino scenarios. As concrete examples of promising neutrino detectors we have chosen the ${}^{64,66}$Zn isotopes, contents of (i) the semiconductor CdZnTe (COBRA experiment) and (ii) the crystal scintillators ZnMoO${}_4$ and ZnWO${}_4$. These materials are quite advantageous for measuring double-$\beta$-decay events and for potential use in studying current neutrino physics issues. We concentrate on the evaluation of folded differential cross sections, ${[d\sigma \left(\omega \right)/d\omega ]}_{\mathrm{fold}}$, and flux-averaged cumulative cross sections, ${[d\sigma \left(\omega \right)/d\omega ]}_{\mathrm{fold}}^{\mathrm{cum}}$, as well as total cross sections, $\langle {\sigma }_{\mathrm{tot}}\rangle$, of the above Zn isotopes by adopting several realistic SN neutrino models parametrized by the neutrino temperature or the mean neutrino energy and the width of the aforementioned distributions.

Background: Short-range correlations (SRC) are an important ingredient of the dynamics of nuclei.

Purpose: An approximate method to quantify the magnitude of the two-nucleon (2N) and three-nucleon (3N) short-range correlations and their mass dependence is proposed.

Method: The proposed method relies on the concept of the “universality” or “local nuclear character” of the SRC. We quantify the SRC by computing the number of independent-particle model (IPM) nucleon pairs and triples which reveal beyond-mean-field behavior. It is argued that those can be identified by counting the number of nucleon pairs and triples in a zero relative orbital momentum state. A method to determine the quantum numbers of pairs and triples in an arbitrary mean-field basis is outlined.

Results: The mass dependence of the 2N and 3N SRC is studied. The predictions are compared to measurements. This includes the ratio of the inclusive inelastic electron scattering cross sections of nuclei to ${}^2$H and ${}^3$He at large values of the Bjorken variable. Corrections stemming from the center-of-mass motion of the pairs are estimated.

Conclusions: We find that the relative probability per nucleon for 2N and 3N SRC has a soft dependence with mass number $A$ and that the proton-neutron 2N SRC outnumber the proton-proton (neutron-neutron) 2N SRC. A linear relationship between the magnitude of the EMC effect and the predicted number of proton-neutron SRC pairs is observed. This provides support for the role of local nuclear dynamics on the EMC effect.

A new averaging process of the calculation of α-decay half-lives for heavy and superheavy nuclei is studied in the framework of a deformed density-dependent cluster model. The potential between a spherical α particle and a deformed daughter nucleus is calculated numerically from the double-folding model by the multipole expansion method. The nuclear potential is calculated at each α-particle emission angle applying the Bohr-Sommerfeld condition at each case. The penetration factors and the half-lives for all the emission angles are evaluated with the new averaging process and compared with older values based on a fixed value of the nuclear potential depth. Finally, the half-lives of 83 even-even heavy nuclei in the atomic-number range 82–118 are calculated by the two methods and compared with their experimental values and the corresponding half-lives of the spherical daughter nuclei.

In this paper we investigate the rotational band built upon a two-quasiparticle $8^{-}$ isomeric state of ${}^{252}$No up to spin $I^{\pi }$ $=$ ${22}^{-}$. The excited states of the band were populated with the ${}^{206}$Pb(${}^{48}\text{Ca},2n$) fusion-evaporation reaction. An unambiguous assignment of the structure of the $8^{-}$ isomer as a $7/2^{+}{\left[624\right]}_{\nu }\otimes 9/2^{-}{\left[734\right]}_{\nu }$ configuration has been made on the basis of purely experimental data. Comparisons with triaxial self-consistent Hartree-Fock-Bogoliubov calculations using the D1S force and breaking time-reversal as well as $z$-signature symmetries are performed. These predictions are in agreement with present measurements. Mean-field calculations extended to similar states in ${}^{250}$Fm support the interpretation of the same two-neutron quasiparticle structure as the bandhead in both $N=150$ isotones.

The sensitivities of isospin asymmetry and collision geometry dependencies of participant (overlapping region)-spectator (quasiprojectile and quasitarget region) matter towards the symmetry energy using the isospin quantum molecular dynamical model are explored. Particularly, the difference of the number of nucleons in the overlapping zone to the quasi-projectile-target matter is found to be quite sensitive to the symmetry energy at semiperipheral geometries compared to the individual yield. It gives us a clue that this quantity can be used as a measure of isospin migration. Further, the yield of neutrons (charge of the second-largest fragment) is provided as a tool for overlapping region (quasi-projectile-target) matter to check the sensitivity of the above-mentioned observable towards the symmetry energy experimentally.

Isospin effects on multifragmentation properties were studied thanks to nuclear collisions between different isotopes of xenon beams and tin targets. It is shown that, in central collisions leading to multifragmentation, the mean number of fragments and their mean kinetic energy increase with the neutron-richness of the total system. Comparisons with a stochastic transport model allow to attribute the multiplicity increase to the multifragmentation stage, before secondary decay. The total charge bound in fragments is proposed as an alternate variable to quantify preequilibrium emission and to investigate symmetry energy effects.

We study the competition between $\alpha$-type and conventional pair condensation in the ground state of nuclei with neutrons and protons interacting via a charge-independent pairing interaction. The ground state is described by a product of two condensates, one of $\alpha$-like quartets and the other one of pairs in excess relative to the isotope with $N=Z$. It is shown that this ansatz for the ground state gives very accurate pairing correlation energies for nuclei with the valence nucleons above the closed cores ${}^{16}$O, ${}^{40}$Ca, and ${}^{100}$Sn. These results indicate that $\alpha$-type correlations are important not only for the self-conjugate nuclei but also for nuclei away from the $N=Z$ line. In the latter case $\alpha$-like quartets coexist with the collective Cooper pairs formed by the nucleons in excess.

Compton scattering cross sections from ${}^6$Li have been measured at scattering angles of 40${}^{\circ }$–160${}^{\circ }$ using a nearly monoenergetic 60-MeV photon beam at the High Intensity Gamma-Ray Source. A phenomenological model provides an estimate of the sensitivity of the ${}^6$Li($\gamma ,\gamma$)${}^6$Li cross section to the nucleon isoscalar electromagnetic polarizabilities ${\alpha }_s$ and ${\beta }_s$.

Asymptotic normalization coefficients (ANCs) are fundamental nuclear constants playing an important role in nuclear reactions, nuclear structure, and nuclear astrophysics. In this paper the physical reasons for the Coulomb renormalization of the ANC are addressed. Using the Pinkston-Satchler equation the ratio for the proton and neutron ANCs of mirror nuclei is obtained in terms of the Wronskians from the radial overlap functions and regular solutions of the two-body Schrödinger equation with the short-range interaction excluded. This ratio allows one to use microscopic overlap functions for mirror nuclei in the internal region, where they are the most accurate, to correctly predict the ratio of the ANCs for mirror nuclei, which determine the amplitudes of the tails of the overlap functions. Calculations presented for different nuclei demonstrate the Coulomb renormalization effects and independence of the ratio of the nucleon ANCs for mirror nuclei on the channel radius. This ratio is valid both for bound states and resonances. One of the goals of this paper is to draw attention to the possibility of using the Coulomb renormalized ANCs rather than the standard ones, especially when the standard ANCs are too large.

We consider symmetries which arise when two-body interaction matrix elements with isospin $T=0$ are set equal to a constant in a single-$j$-shell calculation. The nucleus ${}^{96}$Cd is used as an example.

The binding energies of deformed even-even nuclei have been analyzed within the framework of a recently proposed microscopic-macroscopic model. We have used the semiclassical Wigner-Kirkwood $\hslash$ expansion up to fourth order, instead of the usual Strutinsky averaging scheme, to compute the shell corrections in a deformed Woods-Saxon potential including the spin-orbit contribution. For a large set of 561 even-even nuclei with $Z\ge 8$ and $N\ge 8$, we find an rms deviation from the experiment of 610 keV in binding energies, comparable to the one found for the same set of nuclei using the finite range droplet model of Möller and Nix (656 keV). As applications of our model, we explore its predictive power near the proton and neutron drip lines as well as in the superheavy mass region. Next, we systematically explore the fourth-order Wigner-Kirkwood corrections to the smooth part of the energy. It is found that the ratio of the fourth-order to the second-order corrections behaves in a very regular manner as a function of the asymmetry parameter $I=(N-Z)/A$. This allows us to absorb the fourth-order corrections into the second-order contributions to the binding energy, which enables us to simplify and speed up the calculation of deformed nuclei.

Using the Glauber theory, we calculate reaction cross sections for the deformed halo nucleus ${}^{31}$Ne. To this end, we assume that the ${}^{31}$Ne nucleus takes the ${}^{30}\text{Ne}+n$ structure. To take into account the rotational excitation of the core nucleus ${}^{30}$Ne, we employ the particle-rotor model (PRM). We compare the results to those in the adiabatic limit of PRM, that is, the Nilsson model, and show that the Nilsson model works reasonably well for the reaction cross sections of ${}^{31}$Ne. We also investigate the dependence of the reaction cross sections on the ground-state properties of ${}^{31}$Ne, such as the deformation parameter and the $p$-wave component in the ground-state wave function.

We use the framework of the $hijing/bb̄$ v2.0 model to simulate high-multiplicity (HM) $p+p$ collision events at the Large Hadron Collider (LHC) to study observables sensitive to possible collective phenomena, such as strong longitudinal color fields (SLCF) modeled by an enhanced string tension ($\kappa$). We focus on the hyperon/meson yield ratios at center-of-mass (c.m.) energy $\sqrt{s}$ $=$ 7 TeV, in the transverse momentum region, $1<p_T<4$ GeV/$c$. For minimum bias events these ratios are well described assuming an energy dependence $\kappa =\kappa \left(s\right)={\kappa }_0{(s/s_0)}^{0.04}\mathrm{GeV}/\mathrm{fm}$ (${\kappa }_0$ $=$ 1 GeV/fm), giving a value $\kappa =2$ GeV/fm at $\sqrt{s}$ $=$ 7 TeV. We compare minimum bias (MB) events to simulated HM events assuming that $\kappa \left(\mathrm{MB}\right)=2$ GeV/fm could grow to an extreme value of $\kappa \left(\mathrm{HM}\right)=5$ GeV/fm that saturates the strangeness suppression factor. With this assumption the model predicts a very strong enhancement of (multi)strange baryon/meson ratios in HM events. If observed, such an enhancement could be also interpreted as a possible signature for formation in HM $p+p$ collision events of a deconfined but out of local thermal equilibrium mini-quark-gluon plasma (mQGP).

A simple hybrid quark-diquark model for the baryons is constructed as a partial solution to the well-known “missing resonances” problem. In this model, the quark-diquark approach is merged with the usual constituent three-quark model. The underlying idea is that the quark-diquark approach describes the excited states while the three-quark model the ground states. The spectrum is calculated through a mass formula, a generalization of the Gürsey-Radicati formula, built to reproduce the rotational and vibrational Regge trajectories. Using the quark-diquark scheme, we were also able to describe the spin-flavor degrees of freedom in the framework of an algebraic model. Moreover, we have constructed a complete classifications of the possible quark-diquark states only based on group theory and thus it can be useful both for other model builders and for experimentalists.