We compute the medium-mass nuclei ${}^{16}\mathrm{O}$ and ${}^{40}\mathrm{Ca}$ using pion-less effective field theory (EFT) at next-to-leading order (NLO). The low-energy coefficients of the EFT Hamiltonian are adjusted to experimental data for nuclei with mass numbers $A=2$ and 3, or alternatively to results from lattice quantum chromodynamics at an unphysical pion mass of 806 MeV. The EFT is implemented through a discrete variable representation in the harmonic oscillator basis. This approach ensures rapid convergence with respect to the size of the model space and facilitates the computation of medium-mass nuclei. At NLO the nuclei ${}^{16}\mathrm{O}$ and ${}^{40}\mathrm{Ca}$ are bound with respect to decay into alpha particles. Binding energies per nucleon are $9\text{–}10$ MeV and $21\text{–}40$ MeV at pion masses of 140 and 806 MeV, respectively.

Photodisintegration reaction rates involving charged particles are relevant to the p-process nucleosynthesis that aims at explaining the production of stable neutron-deficient nuclides heavier than iron. In this study, considering the compound and pre-equilibrium reaction mechanisms, the cross sections and astrophysical rates of $(\gamma ,p)$ and $(\gamma ,\alpha )$ reactions for about 3000 target nuclei with $10\le Z\le 100$ ranging from stable to proton dripline nuclei are computed. To study the sensitivity of the calculations to the optical model potentials (OMPs), both the phenomenological Woods-Saxon and the microscopic folding OMPs are taken into account. The systematic comparisons show that the reaction rates, especially for the $(\gamma ,\alpha )$ reaction, are dramatically influenced by the OMPs. Thus, better determination of the OMP is crucial to reduce the uncertainties of the photodisintegration reaction rates involving charged particles. Meanwhile, a $\gamma$-beam facility at Extreme Light Infrastructure–Nuclear Physics (ELI-NP) is being developed which will open new opportunities to experimentally study the photodisintegration reactions of astrophysical interest. Considering both the important reactions identified by the nucleosynthesis studies and the purpose of complementing the experimental results for the reactions involving $p$ nuclei, the measurements of six $(\gamma ,p)$ and eight $(\gamma ,\alpha )$ reactions based on the $\gamma$-beam facility and the Extreme Light Infrastructure Silicon Strip Array (ELISSA) for the detection of charged particles at ELI-NP are proposed. Furthermore, the geant4 simulations on these $(\gamma ,p)$ and $(\gamma ,\alpha )$ reactions are performed using the calculated cross sections and the features of the $\gamma$-beam facility and the ELISSA detector at ELI-NP. Simultaneously satisfying the minimum detectable limit of the experimental yield and the particle identification of protons and $\alpha$ particles, the minimum required energies of the $\gamma$ beam to measure the six $(\gamma ,p)$ and eight $(\gamma ,\alpha )$ reactions are estimated. It is shown that the direct measurements of these photonuclear reactions based on the $\gamma$-beam facility at ELI-NP within the Gamow windows at the typical temperature of $T_9=2.5$ for the p-process are fairly feasible and promising. We believe that this pivotal work will guide the future photodisintegration experiments at ELI-NP. Furthermore, the expected experimental results will be used to constrain the OMPs of the charged particles, which can eventually reduce the uncertainties of the reaction rates for the p-process nucleosynthesis.

Eloquent display of signatures of including higher-multipole (octupole and hexadecupole) deformations ${\beta }_{\lambda i}$, $i=1,2,\lambda =2–4$, and non-coplanar degrees-of-freedom $\mathrm{\Phi }$ are shown here for the first time as essential, additional variables in low-energy heavy-ion reactions (HIR), within the dynamical cluster-decay model (DCM) of the collective clusterization process. In other words, a description in terms of quadrupole-deformed, “optimally” oriented coplanar nuclei is not sufficient, which therefore calls for both higher-multipole deformations (${\beta }_{3i}$ and ${\beta }_{4i}$; $i=1,2$) and non-coplanarity ($\mathrm{\Phi }\ne 0^{\circ }$) as the additional degrees-of-freedom. Such a convincing, real result appears in terms of the non-compound-nucleus (nCN) effect, the nCN cross section ${\sigma }_{\mathrm{nCN}}$-content in ${\sigma }_{\mathrm{fusion}}$, which is different for different compound nuclei (CN), i.e., CN specific, varying from an almost complete impure to pure CN decay while going successively from (${\beta }_{2i}$, ${\theta }_{2i}^{\mathrm{opt}}$, $\mathrm{\Phi }=0^{\circ }$) to (${\beta }_{2i}\text{−}{\beta }_{4i}$, “compact” oriented ${\theta }_{\mathrm{c}i}$, $\mathrm{\Phi }\ne 0^{\circ }$), which is further independent of the radioactive or nonradioactive nature of CN formed in different entrance channels, i.e., also independent of entrance channel target-projectile nuclei. This study plus our earlier study of spontaneous ${}^{14}\mathrm{C}$-cluster radioactivity provide a new set of variables, in terms of higher-multipole deformations and non-coplanarity degrees-of-freedom, to explore the real outcome of any low-energy HIR (plus spontaneous decay), which could in fact be already close to Nature.

The nonlocal implementation of the dispersive optical model (DOM) provides all the ingredients for distorted-wave impulse-approximation (DWIA) calculations of the $(e,e^{\prime }p)$ reaction. It provides both the overlap function, including its normalization, and the outgoing proton distorted wave. This framework is applied to describe the knockout of a proton from the $0d\frac{3}{2}$ and $1s\frac{1}{2}$ orbitals in ${}^{40}\mathrm{Ca}$ with fixed normalizations of 0.71 and 0.60, respectively. Data were obtained in parallel kinematics for three outgoing proton energies: 70, 100, and 135 MeV. Agreement with the data is as good as, or better than, previous descriptions employing local optical potentials and overlap functions from Woods-Saxon potentials—both with standard nonlocality corrections—whose normalization (spectroscopic factor) and radius were fitted to the data. The present analysis suggests that slightly larger spectroscopic factors are obtained when nonlocal optical potentials are employed than those generated with local potentials. The results further suggest that the chosen kinematical window around 100 MeV proton energy provides the best and cleanest method to employ the DWIA for the analysis of this reaction. The conclusion that substantial ground-state correlations cannot be ignored when describing a closed-shell atomic nucleus is therefore confirmed in detail. To reach these conclusions, it is essential to have a complete description of the nucleon single-particle propagator that accounts for all elastic nucleon-scattering observables in a wide energy domain up to 200 MeV. The current nonlocal implementation of the DOM fulfills this requirement.

We study the thermodynamics of the strange baryon system by using an $S$-matrix formulation of statistical mechanics. For this purpose, we employ an existing coupled-channel study involving $\overline{K}N,\pi \mathrm{\Lambda }$, and $\pi \mathrm{\Sigma }$ interactions in the $S=-1$ sector. A novel method is proposed to extract an effective phase shift due to the interaction, which can subsequently be used to compute various thermal observables via a relativistic virial expansion. As an application of the calculation scheme, we compute the correlation of the net baryon number with strangeness $\left({\chi }_{BS}\right)$ for an interacting hadron gas. We show that the $S$-matrix approach, which entails a consistent treatment of resonances and naturally incorporates the additional hyperon states which are not listed by the Particle Data Group, leads to an improved description of the lattice data over the hadron resonance gas model.

$A(d,p)B$ reactions on heavier nuclei are peripheral at sub-Coulomb energies and can be peripheral even at energies above the Coulomb barrier due to the presence of the distorted waves in the initial and final channels. Usually, to analyze such reactions the distorted-wave Born approximation (DWBA) is used. The DWBA amplitude for peripheral reactions is parametrized in terms of the asymptotic normalization coefficient (ANC) of the bound state $B=\left(nA\right)$. However, in the DWBA, the coupling of the different channels is not taken into account explicitly. The three-body Faddeev equations written as the two-particle Alt-Grassberger-Sandhas (AGS) equations are very suitable for the analysis of the $A(d,p)B$ reactions because they take into account explicitly the coupling of the different channels. It is well known that the overall normalization of the DWBA amplitude or even of the more advanced continuum-discretized coupled channels (CDCC) amplitude for peripheral reactions (both sub-Coulomb and above the Coulomb barrier) is determined by the ANC. However, it is not apparent that it is the case for the AGS solution due to the coupling of the $(d,p)$ channel to other channels. In this paper, it is proved that the sub-Coulomb $A(d,p)B$ reaction amplitude, which is a solution of the two-body AGS equations, is peripheral and is parametrized in terms of the ANC of the bound state $B=\left(nA\right)$ if the corresponding DWBA amplitude is peripheral. Both nonlocal separable and local nuclear interaction potentials between the constituent particles are considered. To prove the peripheral character of the AGS amplitude for the sub-Coulomb $A(d,p)B$ reactions the effective potentials are expressed in terms of the corresponding sub-Coulomb DWBA amplitudes of the different channels. The analysis of the $A(d,p)B$ reactions above the Coulomb barrier requires the inclusion of the optical potentials. Hence, to analyze such reactions, the AGS equations are generalized by including the optical nuclear potentials in the same manner as it is done in the DWBA. The obtained AGS equations contain the DWBA effective potentials with distorted waves generated by the sum of the nuclear optical and the channel Coulomb potentials. It is shown that if the DWBA amplitude is peripheral than this is also the case for the AGS amplitude, which is also parametrized in terms of the ANC of the bound state $B=\left(nA\right)$. The inclusion of the coupling of the different channels in the AGS formalism allows one to improve, compared to the DWBA and CDCC methods, the treatment of peripheral $(d,p)$ reactions at sub-Coulomb energies and at energies above the Coulomb barrier.

Nonidentical particle femtoscopy measures the size of the system emitting particles (“radius”) in heavy-ion collisions as well as the difference between mean emission space-time coordinates of two particle species (“emission asymmetry”). The system created in such collisions at the CERN Large Hadron Collider behaves collectively and its dynamics is well described by hydrodynamic models. A significant emission asymmetry between pions and kaons, coming from collective flow, enhanced by contribution from flowing resonances is predicted. Calculations within the (3+1)D viscous hydrodynamic model coupled to statistical hadronization code Therminator 2, corresponding to Pb-Pb collisions at $\sqrt{s_{NN}}$ = 2.76 TeV, are presented. Femtoscopic radii and emission asymmetry for pion-kaon pairs as a function of collision centrality are obtained. The radii grow linearly with cube root of particle multiplicity density. The emission asymmetry is negative and comparable to the radius, indicating that pions are emitted closer to the center of the system and/or later than kaons. Recent ALICE Collaboration measurements of identical kaon femtoscopy shows that kaons are emitted, on average, $2.1\mathrm{fm}/c$ later than pions. The calculation is modified by introducing such delay. The system source size is only weakly affected. In contrast the pion-kaon emission asymmetry is directly sensitive to such delays and the modified calculation shows significantly lower values of asymmetry. This is an argument that the measurement of the pion-kaon femtoscopic correlation function is a sensitive probe of time delays in particle emission.

A concept to measure the neutron electric charge is presented which employs a precision Talbot-Lau interferometer in a high-intensity pulsed neutron beam. It is demonstrated that the sensitivity for a neutron charge measurement can be improved by up to two orders of magnitude compared to the current best direct experimental limit.

There exists a persistent local deviation in the reactor antineutrino spectra between those measured directly at power reactors through the ${\overline{\nu }}_e+p\to n+e^{+}$ reaction and the currently used reference data. In order to interpret the origin of this spectral anomaly with its peak at 6 MeV, the gross theory of $\beta$ decay was applied to calculate the antineutrino spectra for about 500 fission products (FPs) where the measured spin parities were introduced into calculations for 178 odd(-$N$)–odd(-$Z$) FPs in the framework of the gross theory and the recently measured ground-to-ground transition rate for two FPs dominating the spectrum shaping above 5 MeV. The overall consistency between the calculated and the reference spectra is reasonable, and our result supports the direct measurements of the ${\overline{\nu }}_e$ spectra at power reactors. The anomaly is suggested to originate first with the plutonium isotopes ${}^{239}\mathrm{Pu}$ and ${}^{241}\mathrm{Pu}$, which are closely followed by ${}^{235}\mathrm{U}$.

A model is proposed for a description of the octupole vibrational states based on the nuclear shell model. In this model, a one-octupole-phonon representing the collective octupole vibration across the magic core is introduced onto the shell-model states that are microscopically calculated within the valence nucleon space. With this model, a unified description is now possible for the pure shell-model states made by valence nucleons, and the octupole-phonon states excited on the shell-model states. The model is applied to various nuclei around the ${}^{208}\mathrm{Pb}$ nucleus. Energy levels and electric octupole transition probabilities are well reproduced for both the pure shell-model states and the octupole vibrational states.

The approach called the single-state harmonic oscillator representation of scattering equations (SS-HORSE) to analyze resonant states is generalized to the case of charged particle scattering by using the analytical properties of partial scattering amplitudes and is applied to the study of resonant states in the ${}^5\mathrm{Li}$ nucleus and nonresonant $s$-wave proton-$\alpha$ scattering within the no-core shell model using the JISP16 and Daejeon16 $NN$ interactions. We present also the results of calculations of neutron-$\alpha$ scattering and resonances in the ${}^5\mathrm{He}$ nucleus with Daejeon16 and compare with results published previously using JISP16.

We construct nucleonic microscopic optical potentials by combining the Green's function approach with the coupled-cluster method for ${}^{40}\mathrm{Ca}$ and ${}^{48}\mathrm{Ca}$. For the computation of the ground states of ${}^{40}\mathrm{Ca}$ and ${}^{48}\mathrm{Ca}$, we use the coupled-cluster method in the singles-and-doubles approximation, while for the $A$ = $\pm 1$ nuclei we use particle-attached and particle-removed equation-of-motion method truncated at two-particle–one-hole and one-particle–two-hole excitations, respectively. Our calculations are based on the chiral nucleon-nucleon and three-nucleon interaction ${\mathrm{NNLO}}_{\mathrm{sat}}$, which reproduces the charge radii of ${}^{40}\mathrm{Ca}$ and ${}^{48}\mathrm{Ca}$, and the chiral nucleon-nucleon interaction ${\mathrm{NNLO}}_{\mathrm{opt}}$. In all cases considered here, we observe that the overall form of the neutron scattering cross section is reproduced for both interactions, but the imaginary part of the potential, which reflects the loss of flux in the elastic channel, is negligible. The latter points to neglected many-body correlations that would appear beyond the coupled-cluster truncation level considered in this work. We show that, by artificially increasing the parameter $\eta$ in the Green's function, practical results can be further improved.

Background: Recent work has studied the uncertainty in predictions for $A(d,p)B$ reactions using the distorted-wave Born approximation (DWBA), coming from the parametrization of the effective $dA$ interactions [Lovell et al. Phys. Rev. C 95, 024611 (2017)]. There are different levels of sophistication in reaction theories for one-nucleon transfer reactions, including the adiabatic wave approximation (ADWA) which takes deuteron breakup into account to all orders.

Purpose: In this paper, we quantify the uncertainties associated with the ADWA method that come from the parametrization of the NA interactions and compare ADWA with DWBA.

Method: Similar to Lovell et al. [Phys. Rev. C 95, 024611 (2017)], we use nucleon elastic-scattering data on a wide variety of targets at the appropriate incoming and outgoing energies to constrain the optical potential input to the ADWA theory. Pulling from the ${\chi }^2$ distribution, we obtain 95% confidence bands for the elastic distributions. From the resulting parameters, we predict 95% confidence bands for the $(d,p)$ transfer cross sections. Results obtained with the standard uncorrelated ${\chi }^2$ are compared to those using the correlated ${\chi }^2$ of Lovell et al. [Phys. Rev. C 95, 024611 (2017)]. We also repeat the DWBA calculations for the exact same reactions for comparison purposes.

Results: We find that NA elastic-scattering data provide a significant constraint to the interactions, and, when the uncertainties are propagated to the transfer reactions using ADWA, predictions are consistent with the transfer data.

Conclusions: The angular distributions for ADWA differ from those predicted by DWBA, particularly at small angles. As in Lovell et al. [Phys. Rev. C 95, 024611 (2017)], confidence bands obtained using the uncorrelated ${\chi }^2$ function are unrealistically narrow and become much wider when the correlated ${\chi }^2$ function is considered. For most cases, the uncertainty bands obtained in ADWA are narrower than DWBA when using elastic data of similar quality and range. However, given the large uncertainties predicted from the correlated ${\chi }^2$ function, at this point, the transfer data cannot discriminate between these two methods.

QED first-order radiative corrections to the differential cross section for elastic scattering of deuterons on electrons at rest are calculated. Radiative corrections due to soft- and hard-photon bremsstrahlung from the electron lines, the electron vertex correction, and the electron vacuum polarization are considered. The model-dependent contributions due to the bremsstrahlung from the deuteron and the deuteron vertex correction, depending on its internal structure, are not included. We consider an experimental setup where the final particles are recorded in coincidence and their energies are determined within some uncertainties. Formulas for the relevant kinematical variables, the cross section, and the radiative corrections are derived and numerical results are presented.

We analyze thoroughly the statistical properties of the $1^{-}$ spectrum in energy interval 9.5–18.5 MeV for ${}^{206}\mathrm{Hg}, {}^{204,206,208}\mathrm{Pb}$, and ${}^{210}\mathrm{Po}$ nuclei. To this aim we use the Skyrme interaction SLy4 and the volume pairing interaction, treated in the BCS approximation, as our model Hamiltonian to create a single-particle spectrum and to analyze excited states. The excited states are obtained in the quasiparticle random phase approximation taking into account the coupling between one- and two-phonon states. The obtained spectra (studied by means of the nearest-neighbour spacing distribution, ${\mathrm{\Delta }}_3$–statistics and the Porter-Thomas distribution) indicate on the onset of statistical properties close to those of the Gaussian Orthogonal Ensembles. The comparison of the results, obtained with the aid of the coupling calculated microscopically and by means of the Gaussian random distribution, demonstrates a close similarity in the description of the spreading widths of the Isovector Dipole Giant Resonanse of the considered nuclei. Furthermore, we show that employing the random distribution for the coupling between microscopic one-phonon states and two-phonon states, generated by the Gaussian Orthogonal Ensembles distribution, a good agreement is also obtained with the microscopic description of the decay widths.

The density-dependent finite-range Gogny force has been used to derive the effective Hamiltonian for the shell-model calculations of nuclei. The density dependence simulates an equivalent three-body force, while the finite range gives a Gaussian distribution of the interaction in the momentum space and hence leads to an automatic smooth decoupling between low-momentum and high-momentum components of the interaction, which is important for finite-space shell-model calculations. Two-body interaction matrix elements, single-particle energies, and the core energy of the shell model can be determined by the unified Gogny force. The analytical form of the Gogny force is advantageous to treat cross-shell cases, while it is difficult to determine the cross-shell matrix elements and single-particle energies using an empirical Hamiltonian by fitting experimental data with a large number of matrix elements. In this paper, we have applied the Gogny-force effective shell-model Hamiltonian to the $p$- and $sd$-shell nuclei. The results show good agreements with experimental data and other calculations using empirical Hamiltonians. The experimentally known neutron drip line of oxygen isotopes and the ground states of typical nuclei ${}^{10}\mathrm{B}$ and ${}^{18}\mathrm{N}$ can be reproduced, in which the role of three-body force is non-negligible. The Gogny-force-derived effective Hamiltonian has also been applied to the cross-shell calculations of the $sd\text{−}pf$ shell.

Background: Single-neutron transfer reactions populating states in the continuum are interesting both for structure and astrophysics. In their description often global optical potentials are used for the nucleon-target interactions, and these interactions are typically local. In our work, we study the effects of nonlocality in $(d,p)$ reactions populating continuum states. This work is similar to that of Titus and Nunes [Phys. Rev. C 89, 034609 (2014)] but now for transfer to the continuum.

Purpose: A theory for computing cross sections for inclusive processes $A(d,p)X$ was explored in Potel et al. [Phys. Rev. C 92, 034611 (2015)]. Therein, local optical potentials were used to describe the nucleon-target effective interaction. The goal of the present work is to extend the theory developed in Potel et al. (2015) to investigate the effects of including nonlocality in the effective interaction on the relevant reaction observables.

Method: We implement the $R$-matrix method to solve the nonlocal equations both for the nucleon wave functions and the propagator. We then apply the method to systematically study the inclusive process of $(d,p)$ on ${}^{16}\mathrm{O}, {}^{40}\mathrm{Ca}, {}^{48}\mathrm{Ca}$, and ${}^{208}\mathrm{Pb}$ at 10, 20, and 50 MeV. We compare the results obtained when nonlocal interactions are used with those obtained when local equivalent interactions are included.

Results: We find that nonlocality affects different pieces of the model in complex ways. The competition between the reduction of the propagator and the neutron wave function in the region of interest and the increase of the magnitude of the interaction produces varying effects on the cross section. Depending on the beam energy and the target, the nonelastic breakup can either increase or decrease. Effects on the heavier targets can be as large as $85\%$.

Conclusions: While the nonelastic transfer cross section for each final spin state can change considerably, the main prediction of the model [Potel et al. (2015)], namely the shape of the spin distributions, remains largely unaltered by nonlocality.

A detailed feasibility study on deducing the high-lying single particle components (HLSPCs), which are important but used to be ignored, in the ground and low-lying excited states of even-even light nuclei is performed by analyses of $(p,d)$ reactions with ${}^{12}\mathrm{C}$, ${}^{24}\mathrm{Mg}$, ${}^{28}\mathrm{Si}$, and ${}^{40}\mathrm{Ca}$ targets at 51.93 MeV. Coupled reaction channel analyses have been made for $(p,d)$ transitions to the $j$-forbidden excited states in ${}^{11}\mathrm{C}$ (${\frac{5}{2}}^{-}$; 4.32 MeV), ${}^{23}\mathrm{Mg}$ (${\frac{7}{2}}^{+}$; 2.05 MeV), ${}^{27}\mathrm{Si}$ (${\frac{7}{2}}^{+}$; 2.16 MeV), and ${}^{39}\mathrm{Ca}$ (${\frac{9}{2}}^{-}$; 3.64 MeV), including the major allowed transition components together with direct components of HLSPCs. Spectroscopic amplitudes of the HLSPCs are deduced by fitting the angular distributions of the ground and the $j$-forbidden excited states simultaneously. The present analysis demonstrates for the first time that information about HLSPCs in atomic nuclei can be obtained from analysis of $(p,d)$ reactions.

In this article, using Laplace transformation, an analytical solution is obtained for the DGLAP evolution equation at the next-to-leading order of perturbative QCD. The technique is also employed to extract, in the Laplace $s$-space, an analytical solution for the nuclear structure function, $F_2^A(x,Q^2)$. Firstly, the results for separate nuclear parton distributions for all parton types are presented which include valence quark densities, the anti-quark and strange sea PDFs and finally the gluon distribution. Based on the Laplace transformation, the obtained parton distribution functions and the nuclear structure function in the $x$-space are compared with the results from the AT12 Phys. Rev. C 86, 064301 (2012) model. Our calculations are in good agreement with the available DIS experimental data as well as theoretical models which contain both small and large values of $x$-Bjorken variable. We compare our nuclear PDFs sets with those from other recent collaborations, in particular with the nCTEQ15 and HKN07 sets. The comparison between our results and those from the literature indicates a good agreement.