An extension of the multichannel cluster model (MCCM) is presented to investigate the $\alpha$ decay of odd-mass Bk isotopes from their ground states to more than one rotational band in the daughter Am nuclei. In these cases, the $\alpha$ intensity for the other rotational bands is comparable or dominant with respect to the favored one. Three rotational bands are taken into account for the $\alpha$ decays of ${}^{243,245,247}$Bk from their 3/2${}^{-}$ ground states. The available experimental data concerning fine structure and $\alpha$-decay half-lives are well reproduced within the same framework. Moreover, the ground-state and favored rotational bands are considered for the $\alpha$ decay of ${}^{249}$Bk from its 7/2${}^{+}$ ground state. The calculated results also show good agreement with the latest experimental data [I. Ahmad et al., Phys. Rev. C 87, 054328 (2013)]. This is the first calculation of the $\alpha$ transitions to several rotational bands including favored and unfavored ones within the coupled-channel framework.

In a previous work, certain unitary 9-$j$ symbols were shown to go asymptotically to zero in the large-$j$ limit. In this work, we examine this in more detail and find an approximate power law for some unitary 9-$j$'s in the large-$j$ limit and an exponential decrease for others in this same limit.

Recently, a square-integrable discrete basis, obtained performing a simple analytical local scale transformation to the harmonic oscillator basis, has been proposed and successfully applied to study the properties of two-body systems. Here, the method is generalized to study three-body systems. To test the goodness of the formalism and establish its applicability and limitations, the capture reaction rate for the nucleosynthesis of the Borromean nucleus ${}^6$He (${}^4\text{He}+n+n$) is addressed. Results are compared with previous publications and with calculations based on actual three-body continuum wave functions, which can be generated for this simple case. The obtained results encourage the application to other Borromean nuclei of astrophysical interest such as ${}^9$Be and ${}^{12}$C, for which actual three-body continuum calculations are very involved.

The surrogate reaction method has been used to determine neutron-induced fission cross sections of the short-lived minor actinides ${}^{239}$Np and ${}^{240}$Np in the equivalent neutron energy range of 10.5–16.5 and 9.0–16.0 MeV, respectively. The ${}^{240}$Np and ${}^{242}$Pu compound nuclei are produced at similar excitation energies in ${}^{238}$U(${}^6$Li, $\alpha f$)${}^{240}$Np and ${}^{238}$U(${}^6$Li, $df$)${}^{242}$Pu transfer reactions at $E_{lab}=39.6$ MeV. The fission decay probabilities of ${}^{240}$Np [surrogate of ${}^{239}$Np($n,f$)] and ${}^{242}$Pu [surrogate of ${}^{241}$Pu($n,f$)] compound systems have been measured experimentally as a function of excitation energy to determine ${}^{239}$Np($n,f$) cross sections within the framework of hybrid surrogate ratio method by considering directly measured ${}^{241}$Pu($n,f$) cross sections as reference. Similarly, ${}^{238}$U(${}^7$Li, $\alpha f$)${}^{241}$Np and ${}^{238}$U(${}^7$Li, $tf$)${}^{242}$Pu transfer reactions at $E_{lab}=41.0$ MeV have been used to determine ${}^{240}$Np(n, f) cross sections. The present results for ${}^{239}$Np($n,f$) cross sections have been compared with recently reported ${}^{239}$Np(n, f) cross sections obtained by the surrogate ratio method using ${}^{236}$U(${}^3$He, $p$) and ${}^{238}$U(${}^3$He, $p$) reactions [2] and also have been compared with the predictions of the statistical model code empire-3.1 for the fission barriers obtained from the barrier formula and the evaluated nuclear data libraries such as JENDL-4.0 and ENDF/B-VII.1. The present experimental results for ${}^{239}$Np($n,f$) and ${}^{240}$Np($n,f$) cross sections are found to be reasonably consistent with the empire-3.1 predictions.

The difference between the flow ellipticities of oppositely charged pions $\Delta v_2\equiv v_2\left[{\pi }^{-}\right]-v_2\left[{\pi }^{+}\right]$, measured recently by the STAR Collaboration at the Brookhaven National Laboratory Relativistic Heavy Ion Collider (RHIC) shows a linear dependence on the event charge asymmetry $A_{\pm }\equiv (N_{+}-N_{-})/(N_{+}+N_{-})\text{:}\Delta v_2\left(A_{\pm }\right)=\Delta v_2\left(0\right)+r{A}_{\pm }$ with a slope $r>0$ and a nonzero intercept $\Delta v_2\left(0\right)>0$ on the order of ${10}^{-4}$. We discuss two novel mechanisms, which could explain the nonzero value of the charged elliptic flow $\Delta v_2$ at zero charge asymmetry $A_{\pm }=0$, i.e., the nonzero positive intercept $\Delta v_2\left(0\right)$. Both effects are due to the electric fields created by the colliding ions. These fields have quadrupole asymmetry of the magnitude and the sign needed to account for the nonzero intercept $\Delta v_2\left(0\right)>0$ in the RHIC data. One of the mechanisms also involves the chiral magnetic effect. This mechanism, although negligible at RHIC energies, may become important at the CERN Large Hadron Collider energies.

We outline a novel approach to develop an in-medium shower Monte Carlo event generator based on the higher twist formalism of jet modification. By undoing one of the light-cone integrals that sets the corresponding light-cone momentum to be equal in the amplitude and the complex conjugate, we introduce an uncertainty in the smaller light-cone momentum component. This allows for the generalization of the standard analytic formalism to a Wigner-transform-like formalism, where the nonconjugate large light-cone momentum and position are retained for each parton. Jets are generated event by event by simulating this Wigner transform kernel. Simple results for longitudinal distributions of partons and hadrons from jets propagating through a hot brick of strongly interacting matter are presented. Values of the transport coefficient $\widehat{q}$ are dialed to match phenomenologically relevant cases.

In this work we investigate the photoproduction of radially excited vector mesons off nuclei in heavy ion relativistic collisions. In particular, we analyze the exclusive photoproduction of $\psi \left(2S\right)$ off nuclei, evaluating the coherent and the incoherent contributions to that process. The theoretical framework used in the present analysis is the light-cone dipole formalism and predictions are done for PbPb collisions at the CERN Large Hadron Collider energy of 2.76 TeV. The theoretical uncertainties are analyzed and comparison is also done to the recent ALICE Collaboration data for the $\psi \left(1S\right)$ state photoproduction.

A combined study of the reactions $K^{-}p\to {\Sigma }^0{\pi }^0$, $\Lambda {\pi }^0$, and ${\overline{K}}^{0}n$ at low energies is carried out with a chiral quark-model approach. Good descriptions of the experimental observations are obtained. The roles of the low-lying strangeness $S=-1$ hyperon resonances in these processes are carefully analyzed. We find that (i) in the $K^{-}p\to {\Sigma }^0{\pi }^0$ process, both $\Lambda \left(1405\right)S_{01}$ and $\Lambda \left(1520\right)D_{03}$ play dominant roles. Significant contributions of $\Lambda \left(1670\right)S_{01}$ and $\Lambda \left(1690\right)D_{03}$ could be seen around their threshold; (ii) in the $K^{-}p\to \Lambda {\pi }^0$ process, some obvious evidence of $\Sigma \left(1775\right)D_{15}$ and $\Sigma \left(1750\right)S_{11}$ could be found. Some hints of $\Sigma \left(1620\right)S_{11}$ might exist in the reaction as well. $\Sigma \left(1750\right)S_{11}$ and $\Sigma \left(1620\right)S_{11}$ should correspond to the representations $\left[70{,}^{4}8\right]S_{11}$ and $\left[70{,}^{2}8\right]S_{11}$, respectively; (iii) in the $K^{-}p\to {\overline{K}}^{0}n$ process, the dominant resonances are $\Lambda \left(1405\right)$ and $\Lambda \left(1520\right)$. Some evidence of $\Lambda \left(1690\right)D_{03}$, $\Sigma \left(1670\right)D_{13}$, and $\Sigma \left(1775\right)D_{15}$ could be seen as well. A weak coupling of $\Lambda \left(1670\right)S_{01}$ to $\overline{K}N$ should be needed in the reactions $K^{-}p\to {\Sigma }^0{\pi }^0$ and ${\overline{K}}^{0}n$. Furthermore, by analyzing these reactions, we also find that the $u$-, $t$-channel backgrounds and $s$-channel Born term play crucial roles in the reactions: (i) The angle distributions of $K^{-}p\to {\Sigma }^0{\pi }^0$ are very sensitive to the $u$-, $t$-channel backgrounds and $s$-channel $\Lambda$ pole; (ii) the reaction $K^{-}p\to \Lambda {\pi }^0$ is dominated by the $u$-, $t$-channel backgrounds and the ground $P$-wave state $\Sigma \left(1385\right)P_{13}$; (iii) while the reaction $K^{-}p\to {\overline{K}}^{0}n$ is governed by the $t$-channel background, and $\Sigma \left(1385\right)P_{13}$ also plays an important role in this reaction.

To improve the effective interactions in the $pf$ shell, it is important to measure the single-particle and single-hole states near the $N$ $=$ 28 shell gap. In this paper, the neutron spectroscopic factors of hole states from the unstable neutron-rich ${}^{45}$Ar ($Z$ $=$ 18,$N$ $=$ 27) nucleus have been studied using the ${}^1$H(${}^{46}$Ar,$d$) ${}^{45}$Ar transfer reaction in inverse kinematics. Comparison of our results with the particle states of ${}^{45}$Ar produced in ${}^2$H(${}^{44}$Ar, $p$) ${}^{45}$Ar reaction shows that the two reactions populate states with different angular momenta. Using the angular distributions, we are able to confirm the spin assignments of four low-lying states of ${}^{45}$Ar. These are the ground state ($f_{7/2}$), the first-excited state ($p_{3/2}$), and the $s_{1/2}$ and $d_{3/2}$ states. While large basis shell-model predictions describe spectroscopic properties of the ground and $p_{3/2}$ states very well, they fail to describe the $s_{1/2}$ and $d_{3/2}$ hole states.

We use recent data that show a narrow peak around $\sqrt{s}=2.37\mathrm{GeV}$ in the $pn\to d{\pi }^{+}{\pi }^{-}$ cross section, with about double strength at the peak than in the analogous $pn\to d{\pi }^0{\pi }^0$ reaction, and, assuming that it is due to the excitation of a dibaryon resonance, we evaluate the cross section for the $pn\to pn{\pi }^{+}{\pi }^{-}$ reaction, with the final $pn$ unbound but with the same quantum numbers as the deuteron. We use accurate techniques to determine the final state interaction in the case of the $pn$ forming a deuteron or a positive energy state, which allow us to get the $pn\to pn{\pi }^{+}{\pi }^{-}$ cross section with $pn$ in $I=0$ and $S=1$, that turns out to be quite close or saturates the experimental $pn\to pn{\pi }^{+}{\pi }^{-}$ total cross section around $\sqrt{s}=2.37\mathrm{GeV}$, depending on the angular momentum assumed. This poses problems to the assumption of the dibaryon hypothesis, which could be rendered more restrictive with future precise data on the $pn\to pn{\pi }^{+}{\pi }^{-}$ reaction.

A study of the Gamow-Teller strength distributions $B$(GT) in the beta decay of ${}^{78}$Sr and ${}^{76,78}$Rb has been made using a total absorption spectrometer (TAS). Following the success in deducing the sign of the deformation for ${}^{76}$Sr, a similar approach is adopted for ${}^{78}$Sr based on a comparison of the measured $B$(GT) with quasiparticle random-phase approximation calculations. This work confirms its previously expected prolate deformation in the ground state. Conclusions about the structure of the odd-odd ${}^{76,78}$Rb isotopes have been drawn based on their measured $B$(GT) distributions.

The activation cross sections of $(d,p)$, $(d,2n)$, $(d,2np+nd+t)$, $(d,2n\alpha )$, and $(d,p\alpha )$ reactions on ${}^{93}$Nb were measured in the energy range from 1 to 20 MeV using the stacked-foil technique. Then, within a simultaneous analysis of elastic scattering and reaction data, the available elastic-scattering data analysis was carried out in order to obtain the optical potential for reaction cross-section calculations. Particular attention was paid to the description of the breakup mechanism and direct reaction stripping and pick-up, followed by pre-equilibrium and compound-nucleus calculations. The measured cross sections as well as all available deuteron activation data of ${}^{93}$Nb were compared with results of local model calculations carried out using the codes fresco and stapre-h and both default and particular predictions of the code talys-1.4 and tendl-2012-evaluated data.

We present a quark model calculation of the charmonium spectrum with self-energy corrections due to the coupling to the meson-meson continuum. The bare masses used in the calculation are computed within the relativized quark model by Godfrey and Isgur. The strong decay widths of $3S$, $2P$, $1D$, and $2D$ $c\overline{c}$ states are also calculated, to set the values of the ${}^3{P}_0$ pair-creation model's parameters we use to compute the vertex functions of the loop integrals. Finally, the nature of the $X\left(3872\right)$ resonance is analyzed and the main possibilities ($c\overline{c}$ state or $D{\overline{D}}^{*}$ molecule) are discussed. According to our results, the $X\left(3872\right)$ is compatible with the meson ${\chi }_{c1}\left(2P\right)$, with $J^{\mathrm{PC}}=1^{++}$, and is thus interpreted as a $c\overline{c}$ core plus higher Fock components due to the coupling to the meson-meson continuum. These $J^{\mathrm{PC}}=1^{++}$ quantum numbers are in agreement with the experimental results found by the LHCb collaboration. In our view, the $X\left(3872\right)$'s mass is lower than the quark model's predictions because of self-energy shifts.

Gamow-Teller (GT) strength distributions of Mg isotopes are investigated within a framework of the deformed quasiparticle random-phase approximation. We found that the $N=20$ shell closure in ${}^{28\sim 34}$Mg was broken by the prolate shape deformation originating from the $\mathit{fp}$-intruder states. The shell closure breaking gives rise to a shift of low-lying GT excited states into high-lying states. Discussions regarding the shell evolution trend of single-particle states around $N=20$ nuclei are also presented with the comparison to other approaches.

High-precision measurement of half-life and $Q_{\alpha }$ value of neutral and highly charged $\alpha$ emitters is a major subject of investigation currently. In this framework, we recently pushed half-life measurements of neutral emitters to a precision of a few per mil. This result was achieved by using different techniques and apparatuses at Istituto Nazionale di Fisica Nucleare Laboratori Nazionali del Sud (INFN-LNS) and GSI Darmstadt. Here we report on ${}^{213}$Fr half-life determination [$T_{1/2}$(${}^{213}$Fr) = 34.14$\pm$0.06 s] at INFN-LNS, detailing the measurement protocol used. Direct comparison with the accepted value in the literature shows a discrepancy of more than three sigma. We propose this new value as a reference, discussing previous experiments.

In an effort to investigate the production of ${}^{74}$Se in $p$-process nucleosynthesis, the ${}^{74}$Ge($p$,$\gamma$)${}^{75}$As reaction cross section was measured in the relevant energy range of $E_p=1.6$–4.2 MeV. The measurements were carried out using the NSCL SuN detector at the University of Notre Dame. The results are in good agreement with previous work, extending the measurements to both lower and higher energies. The measurements are compared to theoretical predictions using the non-smoker and talys nuclear reaction codes. New and improved reaction rates are offered, and these reaction rates are used in a 25M${}_{\odot }$ Type II Supernova model to study their impact on the production of ${}^{74}$Se.

We introduce a new model applying to the core-nucleus and two-neutron system. The Faddeev equations of ${}^6$He-$n$-$n$ and ${}^8$He-$n$-$n$ systems for ${}^8$He and ${}^{10}$He are solved, respectively. The potential of the subsystem in the model has been determined to make a coupling both of the ground state and the excited one inside the core nucleus. By a similar mechanism the three-nucleon system is solved with the three-body force originating from an isobar excitation of the nucleon. Inputting only the information of subsystem energy levels and widths we get the coupling constants of rank 1 Yamaguchi potential between the core nucleus and neutron. We calculate the Faddeev three-cluster equations to obtain the low-lying energy levels of ${}^8$He and ${}^{10}$He. The 1${}^{-}$ state of ${}^{10}$He, which has not been detected yet in experiments, is located in the energy level between the 0${}^{+}$ and 2${}^{+}$ states.

The population of the high-spin states in ${}^{140}$Nd was investigated using the reaction ${}^{96}$Zr(${}^{48}$Ca,4$n$). The results from two experiments, one with the EUROBALL array and one with the JUROGAM II+RITU+GREAT setup employing the recoil decay tagging technique, have been combined to develop a very detailed level scheme for ${}^{140}$Nd. Twelve bands of quadrupole transitions and eleven bands of dipole transitions were identified and their connections to low-lying states were established. Calculations using the cranked Nilsson-Strutinsky and the tilted axis cranking models were used to interpret the observed structures. The overall good agreement between the experimental results and the calculations assuming a triaxial shape of the nucleus strongly support the existence of a stable triaxial shape at high spins in this mass region.

We analyze hypernuclei coming from fragmentation and multifragmentation of spectator residues obtained in relativistic ion collisions. These hypernuclei have a broad distribution in masses and isospin. They reach beyond the neutron and proton drip lines, and they are expected to be stable with respect to neutron and proton emission. This gives us the opportunity to investigate the properties of exotic hypernuclei, as well as the properties of normal nuclei beyond the drip lines, which can be produced after weak decay of such hypernuclei.

We present shell-model calculations showing that residual interaction-induced configuration mixing enhances the rate of neutral current de-excitation of thermally excited nuclei into neutrino-antineutrino pairs. Though our calculations reinforce the conclusions of previous studies that this process is the dominant source of neutrino pairs near the onset of neutrino trapping during stellar collapse, our shell-model result has the effect of increasing the energy of these pairs, possibly altering their role in entropy transport in supernovae.