The five-dimensional collective Hamiltonian based on the covariant density functional theory is applied to investigate the observed tidal wave mode in the yrast band of ${}^{102}\mathrm{Pd}$. The energy spectra, the relations between the spin and the rotational frequency, and the ratios of $B\left(E2\right)/\mathcal{J}\left(I\right)$ in the yrast band are well reproduced by introducing the empirical $ab$ formula for the moments of inertia. This $ab$ formula is related to the fourth order effect of collective momentum in the collective Hamiltonian. It is also shown that the shape evolution in the tidal wave is determined microscopically by the competition between the rotational kinetic energy and the collective potential in the framework of the collective Hamiltonian.

Lifetimes of the yrast states in ${}^{180}\mathrm{Pt}$ have been measured from $4^{+}$ to $8^{+}$ using the recoil distance Doppler-shift technique in the coincidence mode. These states were populated by the reaction ${}^{156}\mathrm{Gd}({}^{28}\mathrm{Si},4n){}^{180}\mathrm{Pt}$ at a beam energy of 144 MeV. The differential decay curve method was applied to determine the lifetimes from experimental coincidence data. The $B\left(E2\right)$ values extracted from lifetimes increase with increasing spin, implying rotor behavior, but do not show the typical shape coexistence where the $B\left(E2\right)$ values present a rapid increase at very low spins. Calculations based on the triaxial projected shell model were performed for the yrast states in ${}^{180}\mathrm{Pt}$ and the results of both energies and $E2$ transition probabilities reproduce the experimental data very well. The result also shows that a better description of the yrast band in ${}^{180}\mathrm{Pt}$ requires consideration of the $\gamma$ degree of freedom.

Thermal neutron capture $\gamma$-ray spectra for ${}^{16,17,18}\mathrm{O}$ and ${}^2\mathrm{H}$ have been measured with guided cold neutron beams from the Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) reactor and the Budapest Research Reactor (BRR) on natural and ${}^{17,18}\mathrm{O}$ enriched ${\mathrm{D}}_2\mathrm{O}$ targets. Complete neutron capture $\gamma$-ray decay schemes for the ${}^{16,17,18}\mathrm{O}$($\mathrm{n},\gamma$) reactions were measured. Absolute transition probabilities were determined for each reaction by a least-squares fit of the $\gamma$-ray intensities to the decay schemes after accounting for the contribution from internal conversion. The transition probability for the 870.76-keV $\gamma$ ray from ${}^{16}\mathrm{O}$($\mathrm{n},\gamma$) was measured as $P_{\gamma }\left(871\right)=96.6 \pm 0.5\%$ and the thermal neutron cross section for this $\gamma$ ray was determined as $0.164\pm 0.003$ mb by internal standardization with multiple targets containing oxygen and stoichiometric quantities of hydrogen, nitrogen, and carbon whose $\gamma$-ray cross sections were previously standardized. The $\gamma$-ray cross sections for the ${}^{17,18}\mathrm{O}$($\mathrm{n},\gamma$) and ${}^2\mathrm{H}$($\mathrm{n},\gamma$) reactions were then determined relative to the 870.76-keV $\gamma$-ray cross section after accounting for the isotopic abundances in the targets. We determined the following total radiative thermal neutron cross sections for each isotope from the $\gamma$-ray cross sections and transition probabilities; ${\sigma }_0({}^{16}\mathrm{O})=0.170\pm 0.003$ mb; ${\sigma }_0({}^{17}\mathrm{O})=0.67\pm 0.07$ mb; ${\sigma }_0({}^{18}\mathrm{O})=0.141\pm 0.006$ mb; and ${\sigma }_0({}^2\mathrm{H})=0.489\pm 0.006$ mb.

Excitation function of the reaction ${}^{60}\mathrm{Ni}\left(p,\gamma \right){}^{61}\mathrm{Cu}$ was measured via the activation technique in the energy range of 1.3–16.0 MeV using a low-energy accelerator and a small cyclotron. The results are comparable to those previously obtained via prompt γ counting. In addition excitation functions of the more common competing ${}^{60}\mathrm{Ni}\left(p,n\right){}^{60}\mathrm{Cu}$ and ${}^{60}\mathrm{Ni}\left(p,\alpha \right){}^{57}\mathrm{Co}$ reactions were also measured. Theoretical calculations on proton-induced reactions on ${}^{60}\mathrm{Ni}$ were performed using the nuclear model code talys. The results suggest that near the threshold of the reaction the compound nucleus mechanism dominates. Thereafter the contribution of direct interactions becomes rather strong, especially between 4 and 6 MeV, i.e., just below the threshold of the ${}^{60}\mathrm{Ni}\left(p,n\right){}^{60}\mathrm{Cu}$ reaction. The cross section at the maximum of the excitation function of each of the three reactions, namely, ${}^{60}\mathrm{Ni}\left(p,\gamma \right){}^{61}\mathrm{Cu},{}^{60}\mathrm{Ni}\left(p,n\right){}^{60}\mathrm{Cu}$, and ${}^{60}\mathrm{Ni}\left(p,\alpha \right){}^{57}\mathrm{Co}$, amounts to 2, 320, and 85 mb, respectively. The $(p,n)$ reaction is thus the most commonly occurring process, and the $(p,\gamma )$ reaction is the weakest, possibly due to higher probability of particle emission than γ-ray emission from the highly excited intermediate nucleus ${}^{61}\mathrm{Cu}$ formed in the interaction of a proton with the target nucleus ${}^{60}\mathrm{Ni}$.

Within the framework of a multiphase transport model (AMPT), the $\varphi$-meson production is studied in $d+\text{Au}$ collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}=200$ GeV in the forward ($d$-going, $1.2<y<2.2$) and backward (Au-going, $-2.2<y<-1.2$) directions. The AMPT model with string melting version (parton cascade turning on) describes the experimental data well, while the pure hadronic transport scenario of the AMPT model underestimates the $\varphi$-meson production rate in comparison with the data. Detailed investigations including the rapidity, transverse momentum, and collision system size dependencies of $\varphi$-meson nuclear modification factor indicate that a combination of the initial-state effect and a follow-up parton cascade is required in the AMPT model to describe the data. Similar calculations are also present in $p+\text{Pb}$ collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}=5.02$ TeV and $p+p$ collisions at $\sqrt{s_{{}_{\mathrm{NN}}}}=2.76$ TeV. The findings from a comparison of AMPT model study with the data are consistent with that at RHIC energy.

Based on recent experimental data obtained by the CLAS Collaboration, the $\mathrm{\Sigma }\left(1385\right)$ photoproduction off a neutron target at laboratory photon energies $E_{\gamma }$ up to 2.5 GeV is investigated in an effective Lagrangian approach including $s$-, $u$-, and $t$-channel Born-term contributions. The present calculation does not take into account any explicit $s$-channel baryon-resonance contributions; however, in the spirit of duality, we include $t$-channel exchanges of mesonic Regge trajectories. The onset of the Regge regime is controlled by smoothly interpolating between Feynman-type single-meson exchanges and full-fledged Regge-trajectory exchanges. Gauge invariance broken by the Regge treatment is fully restored by introducing contact-type interaction currents that result from the implementation of local gauge invariance in terms of generalized Ward-Takahashi identities. The cross sections for the $\gamma n\to K^{+}{\mathrm{\Sigma }}^{*}{\left(1385\right)}^{-}$ reaction are calculated and compared with experimental results from the CLAS and LEPS collaborations. Despite its simplicity, the present theoretical approach provides a good description of the main features of the data. However, the parameters fitted to the data show that the gauge-invariance-restoring contact term plays a large role, which may point to large contributions from final-state interactions.

Proton spin is investigated in chiral effective field theory through an examination of the singlet axial charge, $a_0$, and the two nonsinglet axial charges, $a_3$ and $a_8$. Finite-range regularization is considered as it provides an effective model for estimating the role of disconnected sea-quark loop contributions to baryon observables. Baryon octet and decuplet intermediate states are included to enrich the spin and flavor structure of the nucleon, redistributing spin under the constraints of chiral symmetry. In this context, the proton spin puzzle is well understood with the calculation describing all three of the axial charges reasonably well. The strange quark contribution to the proton spin is negative with magnitude 0.01. With appropriate $Q^2$ evolution, we find the singlet axial charge at the experimental scale to be ${\widehat{a}}_0=0.{31}_{-0.05}^{+0.04}$, consistent with the range of current experimental values.

A radiopure cadmium tungstate crystal scintillator, enriched in ${}^{106}\mathrm{Cd}$ to 66%, with mass of 216 g $\left({}^{106}\mathrm{Cd}{\text{WO}}_4\right)$, was used to search for double-$\beta$ decay processes in ${}^{106}\mathrm{Cd}$ in coincidence with four ultra-low-background high-purity germanium detectors in a single cryostat. Improved limits on the double-$\beta$ processes in ${}^{106}\mathrm{Cd}$ have been set on the level of ${10}^{20}-{10}^{21}$ yr after 13 085 h of data taking. In particular, the half-life limit on the two-neutrino electron capture with positron emission, $T_{1/2}^{2\nu \varepsilon {\beta }^{+}}\ge 1.1\times {10}^{21}$ yr, has reached the region of theoretical predictions. With this half-life limit the effective nuclear matrix element for the $2\nu \varepsilon {\beta }^{+}$ decay is bounded as $M_{\mathrm{eff}}^{2\nu \varepsilon {\beta }^{+}}\le 1.1$. The resonant neutrinoless double-electron captures to the 2718-, 2741-, and 2748-keV excited states of ${}^{106}\mathrm{Pd}$ are restricted at the level of $T_{1/2}\ge (8.5\times {10}^{20}-1.4\times {10}^{21})$ yr.

We explore effects of the screening due to the relativistic electron-positron plasma and presence of resonances in the secondary reactions leading to $A=7$ nuclei during the Big Bang nucleosynthesis. In particular, we investigate and examine possible low-lying resonances in the ${}^7\mathrm{Be}$ $\left({}^3\mathrm{He},\gamma \right)$ ${}^{10}\mathrm{C}$ reaction and examine the resultant destruction of ${}^7\mathrm{Be}$ for various resonance locations and strengths. While a resonance in the ${}^{10}\mathrm{C}$ compound nucleus is thought to have negligible effects we explore the possibility of an enhancement from plasma screening that may adjust the final ${}^7\mathrm{Be}$ abundance. We find the effects of relativistic screening and possible low-lying resonances to be relatively small in the standard Early Universe models.

Inelastic proton scattering at energies of a few hundred million electron volts and extreme forward angles selectively excite the isovector spin-flip $M1$ ($\mathrm{IVS}M1$) resonance. A method based on isospin symmetry is presented to extract its electromagnetic transition strength from the $(p,p^{\prime })$ cross sections. It is applied to ${}^{48}\mathrm{Ca}$, a key case for an interpretation of the quenching phenomenon of the spin-isospin response, and leads to a $M1$ strength consistent with an older $(e,e^{\prime })$ experiment excluding the almost two times larger value from a recent $(\gamma ,n)$ experiment. Good agreement with electromagnetic probes is observed in ${}^{208}\mathrm{Pb}$, suggesting the possibility of extracting systematic information on the IVSM1 resonance in heavy nuclei.

We present a shell-model analysis of the $\beta$ decay of ${}^{56}\mathrm{Zn}$. The calculations are performed using isospin-nonconserving Hamiltonians constructed on the basis of the GXPF1A and KB3G interactions. Our theoretical results reproduce the essential features of the decay of ${}^{56}\mathrm{Zn}$ and explain the surprising competition between $\beta$-delayed proton and $\gamma$-ray emission from the isobaric analog state.

Background: ${}^{6,7}\mathrm{Li}$ and ${}^9\mathrm{Be}$ are weakly bound against breakup into their cluster constituents. Breakup location is important for determining the role of breakup in above-barrier complete fusion suppression. Recent works have pointed out that experimental observables can be used to separate near-target and asymptotic breakup.

Purpose: Our purpose is to distinguish near-target and asymptotic direct breakup of ${}^{6,7}\mathrm{Li}$ in reactions with nuclei in different mass regions.

Method: Charged particle coincidence measurements are carried out with pulsed ${}^{6,7}\mathrm{Li}$ beams on ${}^{58}\mathrm{Ni}$ and ${}^{64}\mathrm{Zn}$ targets at sub-barrier energies and compared with previous measurements using ${}^{208}\mathrm{Pb}$ and ${}^{209}\mathrm{Bi}$ targets. A detector array providing a large angular coverage is used, along with time-of-flight information to give definitive particle identification of the direct breakup fragments.

Results: In interactions of ${}^6\mathrm{Li}$ with ${}^{58}\mathrm{Ni}$ and ${}^{64}\mathrm{Zn}$, direct breakup occurs only asymptotically far away from the target. However, in interactions with ${}^{208}\mathrm{Pb}$ and ${}^{209}\mathrm{Bi}$, near-target breakup occurs in addition to asymptotic breakup. Direct breakup of ${}^7\mathrm{Li}$ into $\alpha -t$ is not observed in interactions with ${}^{58}\mathrm{Ni}$ and ${}^{64}\mathrm{Zn}$. However, near-target dominated direct breakup was observed in measurements with ${}^{208}\mathrm{Pb}$ and ${}^{209}\mathrm{Bi}$. A modified version of the Monte Carlo classical trajectory model code platypus, which explicitly takes into account lifetimes associated with unbound states, is used to simulate sub-barrier breakup reactions.

Conclusions: Near-target breakup in interactions with ${}^{6,7}\mathrm{Li}$ is an important mechanism only for the heavy targets ${}^{208}\mathrm{Pb}$ and ${}^{209}\mathrm{Bi}$. There is insignificant near-target direct breakup of ${}^6\mathrm{Li}$ and no direct breakup of ${}^7\mathrm{Li}$ in reactions with ${}^{58}\mathrm{Ni}$ and ${}^{64}\mathrm{Zn}$. Therefore, direct breakup is unlikely to suppress the above-barrier fusion cross section in reactions of ${}^{6,7}\mathrm{Li}$ with ${}^{58}\mathrm{Ni}$ and ${}^{64}\mathrm{Zn}$ nuclei.

The recently measured centrality dependence of high energy jets in proton-lead collisions at the CERN Large Hadron Collider (LHC) is investigated. We hypothesize that events with jets of very high energy (a few hundred GeV) are characterized by a suppressed number of soft particles, thus shifting these events into more peripheral bins. This naturally results in the suppression (enhancement) of the nuclear modification factor, $R_{pA}$, in central (peripheral) collisions. Our calculations suggest that a moderate suppression of the order of $20\%$, for ${10}^3$ GeV jets, can quantitatively reproduce the experimental data. We further extract the suppression factor as a function of jet energy and test our conjecture using available $R_{pA}$ data for various centralities.

Recently lots of effort has been made to obtain the next-to-leading-order and Landau-Pomeranchuk-Migdal corrections to the thermal dilepton emission rate in perturbative QCD. Here we apply these results to the plasma created in heavy-ion collisions and see whether these corrections improve the comparison between theoretical calculations and experimental results for the invariant mass dependence of the dilepton emission rate. In particular, we simulate the quark-gluon plasma produced at the Relativistic Heavy Ion Collider at the Brookhaven National Laboratory and the Large Hadron Collider at CERN using $2+1$-dimensional viscous hydrodynamical simulations. We compare our results to those of the STAR experiment and comment on the need for a nonperturbative determination of the dilepton rate at low invariant mass.

We report on measurements of a charge-dependent flow using a novel three-particle correlator with ALICE in Pb-Pb collisions at the CERN Large Hadron Collider (LHC), and discuss the implications for observation of local parity violation and the chiral magnetic wave (CMW) in heavy-ion collisions. Charge-dependent flow is reported for different collision centralities as a function of the event charge asymmetry. While our results are in qualitative agreement with expectations based on the CMW, the nonzero signal observed in higher harmonics correlations indicates a possible significant background contribution. We also present results on a differential correlator, where the flow of positive and negative charges is reported as a function of the mean charge of the particles and their pseudorapidity separation. We argue that this differential correlator is better suited to distinguish the differences in positive and negative charges expected due to the CMW and the background effects, such as local charge conservation coupled with strong radial and anisotropic flow.

A novel neutron spin resonance technique is presented based on the well-known neutron spin echo method. In a first proof-of-principle measurement using a monochromatic neutron beam, it is demonstrated that relative velocity changes of down to a precision of $4\times {10}^{-7}$ can be resolved, corresponding to an energy resolution of better than 3 neV. Currently, the sensitivity is only limited by counting statistics and not by systematic effects. An improvement by another two orders of magnitude can be achieved with a dedicated setup, allowing energy resolutions in the 10 peV regime. The new technique is ideally suited for investigations in the field of precision fundamental neutron physics, but will also be beneficial in scattering applications.

For the first time, the $\gamma$ decay of excited states has been observed in a nucleus situated in the quadrant south-east of doubly magic ${}^{132}\mathrm{Sn}$, a region in which experimental information so far is limited to ground-state properties. Six $\gamma$ rays with energies of 50, 86, 103, 227, 357, and 602 keV were observed following the $\beta$-delayed neutron emission from ${}^{133}\mathrm{Cd}_{85}$, populated in the projectile fission of a ${}^{238}\mathrm{U}$ beam at the Radioactive Isotope Beam Factory at RIKEN within the EURICA project. The new experimental information is compared to the results of a modern realistic shell-model calculation, the first one in this region very far from stability, focusing in particular on the $\pi 0g_{9/2}^{-1}\otimes \nu 1f_{7/2}$ particle-hole multiplet in ${}^{132}\mathrm{In}_{83}$. In addition, theoretical estimates based on a scaling of the two-body matrix elements for the $\pi h_{11/2}^{-1}\otimes \nu g_{9/2}$ analog multiplet in ${}^{208}\mathrm{Tl}_{127}$, one major proton and one major neutron shell above, are presented.

We derive the cross section for exclusive vector meson production in high-energy deeply inelastic scattering off a deuteron target that disintegrates into a proton and a neutron carrying large relative momentum in the final state. This cross section can be expressed in terms of a novel gluon transition generalized parton distribution (T-GPD); the hard scale in the final state makes the T-GPD sensitive to the short-distance nucleon-nucleon interaction. We perform a toy model computation of this process in a perturbative framework and discuss the time scales that allow the separation of initial- and final-state dynamics in the T-GPD. We outline the more general computation based on the factorization suggested by the toy computation: In particular, we discuss the relative role of “pointlike” and “geometric” Fock configurations that control the parton dynamics of short-range nucleon-nucleon scattering. With the aid of exclusive $J/\psi$ production data at the Hadron-Electron Ring Accelerator at DESY, as well as elastic nucleon-nucleon cross sections, we estimate rates for exclusive deuteron photodisintegration at a future Electron-Ion Collider (EIC). Our results, obtained using conservative estimates of EIC integrated luminosities, suggest that center-of-mass energies $s_{\mathit{NN}}\sim 12{\mathrm{GeV}}^2$ of the neutron-proton subsystem can be accessed. We argue that the high energies of the EIC can address outstanding dynamical questions regarding the short-range quark-gluon structure of nuclear forces by providing clean gluon probes of such “knockout” exclusive reactions in light and heavy nuclei.