Table of contents

Density functional theory (DFT) is a powerful and accurate tool, exploited in nuclear physics to investigate the ground-state and some of the collective properties of nuclei along the whole nuclear chart. Models based on DFT are not, however, suitable for the description of single-particle dynamics in nuclei. Following the field theoretical approach by A Bohr and B R Mottelson to describe nuclear interactions between single-particle and vibrational degrees of freedom, we have taken important steps towards the building of a microscopic dynamic nuclear model. In connection with this, one important issue that needs to be better understood is the renormalization of the effective interaction in the particle-vibration approach. One possible way to renormalize the interaction is by the so-called subtraction method. In this contribution, we will implement the subtraction method in our model for the first time and study its consequences.

Neutron-capture reactions play an important role in heavy element nucleosynthesis, since they are the driving force for the two processes that create the vast majority of the heavy elements. When a neutron capture occurs on a short-lived nucleus, it is extremely challenging to study the reaction directly and therefore the use of indirect techniques is essential. The present work reports on such an indirect measurement that provides strong constraints on the ⁶⁸Ni(n, γ)⁶⁹Ni reaction rate. This is done by populating the compound nucleus ⁶⁹Ni via the β decay of ⁶⁹Co and measuring the γ-ray deexcitation of excited states in ⁶⁹Ni. The β-Oslo method was used to extract the γ-ray strength function and the nuclear level density. In addition the half-life of ⁶⁹Co was extracted and found to be in agreement with previous literature values. Before the present results, the ⁶⁸Ni(n, γ)⁶⁹Ni reaction was unconstrained and the purely theoretical reaction rate was highly uncertain. The new uncertainty on the reaction rate based on the present experiment (variation between upper and lower limit) is approximately a factor of 3. The commonly used reaction libraries JINA-REACLIB and BRUSLIB are in relatively good agreement with the experimental rate. The impact of the new rate on weak r-process calculations is discussed.

An experimental setup for sensitive high-resolution measurements of hyperfine structure spectra of exotic calcium isotopes has been developed and commissioned at the COLLAPS beam line at ISOLDE, CERN. The technique is based on the radioactive detection of decaying isotopes after optical pumping and state selective neutralization (ROC) (Vermeeren et al 1992 Phys. Rev. Lett.68 1679). The improvements and developments necessary to extend the applicability of the experimental technique to calcium isotopes produced at rates as low as few ions s^–1 are discussed. Numerical calculations of laser-ion interaction and ion-beam simulations were explored to obtain the optimum performance of the experimental setup. Among the implemented features are a multi-step optical pumping region for sensitive measurements of isotopes with hyperfine splitting, a high-voltage platform for adequate control of low-energy ion beams and simultaneous β-detection of neutralized and remaining ions. The commissioning of the experimental setup, and the first online results on neutron-rich calcium isotopes are presented.

Alkali ion beams are among the most intense produced by the ISOLDE facility. These were the first to be studied by the ISOLTRAP mass spectrometer and ever since, new measurements have been regularly reported. Recently the masses of very neutron-rich and short-lived cesium isotopes were determined at ISOLTRAP. The isotope ¹⁴⁸Cs was measured directly for the first time by Penning-trap mass spectrometry. Using the new results, the trend of two-neutron separation energies in the cesium isotopic chain is revealed to be smooth and gradually decreasing, similar to the ones of the barium and xenon isotopic chains. Predictions of selected microscopic models are employed for a discussion of the experimental data in the region.

We report on studies of the beta-decays of ³¹Ar, ${}^{\mathrm{20,21}}$Mg, and ¹⁶N performed at the ISOLDE decay station (IDS) at CERN. These studies illustrate how beta-decays measured with the IDS can be used to extract information of astrophysical interest, or to study the structure and decay mechanism of exotic nuclei. We discuss the specific implementation of the IDS designed for this type of studies including detector setups and data acquisition.

In this article, we point out that the effective Hamiltonian for neutrino oscillations in matter is invariant under the transformation of the mixing angle ${\theta }_{12}^{}\to {\theta }_{12}^{}-\pi /2$ and the exchange of first two neutrino masses ${m}_{1}^{}\leftrightarrow {m}_{2}^{}$, if the standard parametrization of lepton flavor mixing matrix is adopted. To maintain this symmetry in perturbative calculations, we present a symmetric formulation of the effective Hamiltonian by introducing an η-gauge neutrino mass-squared difference ${{\rm{\Delta }}}_{* }^{}\equiv \eta {{\rm{\Delta }}}_{31}^{}+(1-\eta ){{\rm{\Delta }}}_{32}^{}$ for $0\leqslant \eta \leqslant 1$, where ${{\rm{\Delta }}}_{{ji}}^{}\equiv {m}_{j}^{2}-{m}_{i}^{2}$ for ${ji}=21,31,32$, and show that only $\eta =1/2$, $\eta ={\cos }^{2}{\theta }_{12}^{}$ or $\eta ={\sin }^{2}{\theta }_{12}^{}$ is allowed. Furthermore, we prove that $\eta ={\cos }^{2}{\theta }_{12}^{}$ is the best choice to derive more accurate and compact neutrino oscillation probabilities, by implementing the approach of renromalization-group equations. The validity of this approach becomes transparent when an analogy is made between the parameter η herein and the renormalization scale μ in relativistic quantum field theories.

The production of prompt photons is one of the most relevant scattering processes studied at hadron–hadron colliders in recent years. This article will give an overview of the different approaches used to simulate prompt photon production in the Sherpa event generator framework. Special emphasis is placed on a complete simulation of this process including fragmentation configurations. As a novel application a merged simulation of $\gamma \gamma$ and $\gamma \gamma +$jet production at NLO accuracy is presented and compared to measurements from the ATLAS experiment.

The parameters of the nuclear energy density have to be adjusted to experimental data. As a result they carry certain uncertainty which then propagates to calculated values of observables. In the present work we quantify the statistical uncertainties of binding energies, proton quadrupole moments and proton matter radius for three UNEDF Skyrme energy density functionals by taking advantage of the knowledge of the model parameter uncertainties. We find that the uncertainty of UNEDF models increases rapidly when going towards proton or neutron rich nuclei. We also investigate the impact of each model parameter on the total error budget.

The bound states of ¹⁰Be have been studied by removing single neutrons from ¹¹Be nuclei. A 2.8 MeV u^–1 beam of ¹¹Be was produced at ISOLDE, CERN and directed on to both proton and deuteron targets inducing one-neutron removal reactions. Charged particles were detected to identify the two reaction channels (d, t) and (p, d), and the individual states in ¹⁰Be were identified by gamma detection. All bound states but one were populated and identified in the (d, t) reaction. The combination of REX-ISOLDE and MINIBALL allowed for a clean separation of the high-lying states in ¹⁰Be. This is the first time these states have been separated in a reaction experiment. Differential cross sections have been calculated for all the reaction channels and compared to DWBA calculations. Spectroscopic factors are derived and compared to values from the litterature. While the overall agreement between the spectrocopic factors is poor, the ratio between the ground state and the first excited state is in agreement with the previous measured ones. Furthermore, a significant population of the ${2}_{2}^{+}$ state is observed, which which may indicate the presence of multi-step processes at our beam energy.

We review major experiments and results obtained by the on-line low temperature nuclear orientation method at the NICOLE facility at ISOLDE, CERN since the year 2000 and highlight their general physical impact. This versatile facility, providing a large degree of controlled nuclear polarization, was used for a long-standing study of magnetic moments at shell closures in the region Z = 28, N = 28–50 but also for dedicated studies in the deformed region around A ∼ 180. Another physics program was conducted to test symmetry in the weak sector and constrain weak coupling beyond V–A. Those two programs were supported by careful measurements of the involved solid state physics parameters to attain the full sensitivity of the technique and provide interesting interdisciplinary results. Future plans for this facility include the challenging idea of measuring the beta–gamma–neutron angular distributions from polarized beta delayed neutron emitters, further test of fundamental symmetries and obtaining nuclear structure data used in medical applications. The facility will also continue to contribute to both the nuclear structure and fundamental symmetry test programs.

The idea of production of short-lived radioisotopes with the on-line technique has it roots in the early 1950s. In 1964 this became a reality when CERN approved an experiment at the 600 MeV proton synchro-cyclotron, the SC. The first experiments were performed in 1967 and since then the ISOLDE programme has gradually developed into a major undertaking. Since 1992 the ISOLDE Radioactive Beam Facility is linked to an external proton beam from the PS Booster. Today this 50 years old 'lady' is more vital than ever. With the successful start of HIE-ISOLDE in 2015 one may conclude that the facility is ready to face the next half century with the boost of the success and the necessary knowledge to face new challenges. In this introductory article we give an overview of the history and pick up a few examples along the nuclear chart as illustrations of the experimental achievements.

High-resolution γ-ray spectroscopy has been established at ISOLDE for nuclear-structure and nuclear-reaction studies with reaccelerated radioactive ion beams provided by the REX-ISOLDE facility. The MINIBALL spectrometer comprises 24 six-fold segmented, encapsulated high-purity germanium crystals. It was specially designed for highest γ-ray detection efficiency which is advantageous for low-intensity radioactive ion beams. The MINIBALL array has been used in numerous Coulomb-excitation and transfer-reaction experiments with exotic ion beams of energies up to 3 MeV A^–1. The physics case covers a wide range of topics which are addressed with beams ranging from neutron-rich magnesium isotopes up to heavy radium isotopes. In the future the HIE-ISOLDE will allow the in-beam γ-ray spectroscopy program to proceed with higher secondary-beam intensity, higher beam energy and better beam quality.

Nuclear-reaction studies have until now constituted a minor part of the physics program with post-accelerated beams at ISOLDE, mainly due to the maximum energy of REX-ISOLDE of around 3 MeV/u that limits reaction work to the mass region below A = 100. We give an overview of the current experimental status and of the physics results obtained so far. Finally, the improved conditions given by the HIE-ISOLDE upgrade are described.

Several approximate equalities among the matrix elements of the Cabibbo–Kobayashi–Maskawa (CKM) and Pontecorvo–Maki–Nakagawa–Sakata (PMNS) matrices imply that hidden symmetries may exist and be common for both quark and neutrino sectors. The charge parity (CP) phase of the CKM matrix (${\delta }_{\mathrm{CKM}}$) is involved in these equalities and can be investigated when these equalities turn into several equations. As we substitute those experimentally measured values of the three mixing angles into the equations for quarks, it is noted that one of the equations which holds exactly has a solution ${\delta }_{\mathrm{CKM}}=({68.95}_{-1.15}^{+1.15})^\circ$. That value accords with $({69.1}_{-3.85}^{+2.02})^\circ$ determined from available data. Generalizing the scenario to the lepton sector, the same equality determines the leptonic CP phase ${\delta }_{\mathrm{PMNS}}$ to be $({275.20}_{-1.15}^{+1.15})^\circ$. Thus we predict the value of ${\delta }_{\mathrm{PMNS}}$ from the equation. So far there is no direct measurement on ${\delta }_{\mathrm{PMNS}}$, but a recent analysis based on the neutrino oscillation data prefers a phase close to 270°.

We study the heavy neutral scalar decays into standard model electroweak gauge bosons in the context of the littlest Higgs model. We focus our attention on the ${{\rm{\Phi }}}^{0}\to {WW},\gamma V$ processes induced at the one-loop level, with $V=\gamma ,Z$. Since the branching ratios of the ${{\rm{\Phi }}}^{0}\to \gamma V$ decays are very suppressed, only the ${{\rm{\Phi }}}^{0}\to {WW}$ process is analyzed in the framework of possible experimental scenarios by using heavy scalar masses between 1.6 TeV and 3.3 TeV. The branching ratio for the ${{\rm{\Phi }}}^{0}\to {WW}$ decay is of the order of 10⁻³ throughout the interval $2\,\mathrm{TeV}\lt f\lt 4\,\mathrm{TeV}$, which represents the global symmetry breaking scale of the theory. Thus, the associated production cross section for ${pp}\to {{\rm{\Phi }}}^{0}X\to {WW}$ is estimated, finding around ten events for ${m}_{{{\rm{\Phi }}}^{0}}\approx 1.6\,\mathrm{TeV}$ at best.

We have used the SmallGroups library of groups, together with the computer algebra systems GAP and Mathematica, to search for groups with a three-dimensional irreducible representation in which one of the group generators has a twice-degenerate eigenvalue while another generator has non-degenerate eigenvalues. By assuming one of these group generators to commute with the charged-lepton mass matrix and the other one to commute with the neutrino (Dirac) mass matrix, one derives group-theoretical predictions for the moduli of the matrix elements of either a row or a column of the lepton mixing matrix. Our search has produced several realistic predictions for either the second row, or the third row, or for any of the columns of that matrix.

In this paper we study the weak decays of $J/\psi$ and ${\rm{\Upsilon }}(1S)$. The cases when the final mesons are pseudo-scalars or vectors are considered. Using the Bethe–Salpeter method, we calculate the hadronic transition amplitude and give the form factors. The energy spectra of leptons for the semi-leptonic channels are also presented for convenience. In the calculation of non-leptonic decays, the naive factorization is applied. And all types of such channels, namely, flavor-favored or suppressed and color-favored or suppressed, are calculated. Our results show that, for the semi-leptonic decay modes, the largest branching ratios are of the order of 10⁻¹⁰ both for $J/\psi$ and ${\rm{\Upsilon }}(1S)$ decays, and the largest branching ratios of non-leptonic decays are of the order of 10⁻⁹ for $J/\psi$ and 10⁻¹⁰ for ${\rm{\Upsilon }}(1S)$.

Resonant production of color octet electrons, e₈, at the FCC based e–p colliders is analyzed. It is shown that e-FCC will cover much a wider region of e₈ masses compared to the LHC. Moreover, with the highest electron beam energy, the e₈ search potential of the e-FCC exceeds that of the FCC p–p collider. If e₈ is discovered earlier by the FCC p–p collider, e-FCC will give an opportunity to handle very important additional information. For example, the compositeness scale can be probed up to the hundreds of TeV region.

First results are reported on the ground state configurations of the neutron-rich ^29,30Na isotopes, obtained via Coulomb dissociation (CD) measurements. The invariant mass spectra of these nuclei have been obtained through measurement of the four-momenta of all decay products after Coulomb excitation of those nuclei on a ²⁰⁸Pb target at energies of 400–430 MeV/nucleon using the FRS-ALADIN-LAND setup at GSI, Darmstadt. Integrated inclusive CD cross-sections (CD) of 89 (7) mb and 167 (13) mb for one neutron removal from ²⁹Na and ³⁰Na, respectively, have been extracted up to an excitation energy of 10 MeV. The major part of one neutron removal, CD cross-sections of those nuclei populate the core, in its ground state. A comparison with the direct breakup model, suggests the predominant occupation of the valence neutron in the ground state of ²⁹Na $(3/{2}^{+})$ and ³⁰Na $({2}^{+})$ is the d-orbital with a small contribution from the s-orbital, which are coupled with the ground state of the core. One of the major components of the ground state configurations of these nuclei are ²⁸Na${}_{{gs}}({1}^{+})\otimes {\nu }_{s,d}$ and ²⁹Na${}_{{gs}}(3/{2}^{+})\otimes {\nu }_{s,d}$, respectively. The ground state spin and parity of these nuclei obtained from this experiment are in agreement with earlier reported values. The spectroscopic factors for the valence neutron occupying the s and d orbitals for these nuclei in the ground state have been extracted and reported for the first time. A comparison of the experimental findings with shell model calculation using the MCSM suggests a lower limit of around 4.3 MeV of the sd–pf shell gap in ³⁰Na.

The phenomenological generalized coherent-state model Hamiltonian is amended with a many-body term describing a set of nucleons moving in a spherical shell-model mean field and interacting among themselves with pairing, as well as with a particle–core interaction involving a harmonic quadrupole–quadrupole, an anharmonic hexdecapole–hexdecapole and a spin–spin interaction. The model Hamiltonian is treated in a restricted space consisting of the core projected states associated to the bands ground, $\beta ,\gamma ,\widetilde{\gamma },{1}^{+}$ and $\widetilde{{1}^{+}}$ and two proton-aligned quasiparticles coupled with the states of the ground band to a total angular momentum. The chirally transformed particle–core states are also included. The Hamiltonian contains two terms which are not invariant to the chiral transformations relating the right-handed trihedral $({{\bf{J}}}_{{\bf{F}}},{{\bf{J}}}_{{\bf{p}}},{{\bf{J}}}_{{\bf{n}}})$ and the left-handed ones $(-{{\bf{J}}}_{{\bf{F}}},{{\bf{J}}}_{{\bf{p}}},{{\bf{J}}}_{{\bf{n}}})$, $({{\bf{J}}}_{{\bf{F}}},-{{\bf{J}}}_{{\bf{p}}},{{\bf{J}}}_{{\bf{n}}})$, $({{\bf{J}}}_{{\bf{F}}},{{\bf{J}}}_{{\bf{p}}},-{{\bf{J}}}_{{\bf{n}}})$ where ${{\bf{J}}}_{{\bf{F}}},{{\bf{J}}}_{{\bf{p}}},{{\bf{J}}}_{{\bf{n}}}$ are the angular momenta carried by fermions, proton and neutron bosons, respectively. The energies defined with the particle–core states form four chiral bands, two of them being degenerate. The electromagnetic properties of the chiral bands are investigated and the results are compared with the experimental data of ¹³⁸Nd.

Bremsstrahlung emission by relativistic electrons in collisions with medium heavy spin-zero nuclei is calculated within the plane-wave Born approximation. Coulomb distortion is estimated by a comparison with the Dirac partial-wave theory at energies up to 20 MeV. When integrated over the photon emission angle, the bremsstrahlung spectra help to explain the background of the nuclear excitation spectra in ¹⁵⁰Nd $(e,e^{\prime} )$ reactions which were recently measured on an absolute scale.

Recent experiments on lead (${{\rm{Pb}}}_{82}^{208}$) nuclei have observed the celebrated phenomenon of the neutron skin thickness of low energy nuclear physics. Skin thickness provides a measure of the extension of the spatial distribution of neutrons inside the atomic nucleus than protons. We have studied the effect of neutron skin thickness on inclusive prompt photon production in Pb + Pb collisions at Large Hadron Collider energies. We have calculated the 'central-to-peripheral ratio' (${R}_{\mathrm{cp}}$) of prompt photon production with and without accounting for the neutron skin effect. The neutron skin causes a characteristic enhancement of the ratio, in particular at forward rapidity, which is distinguishable in our calculation. However, a very precise direct photon measurement up to large transverse momenta would be necessary to constrain the feature in experiment.

Within the dinuclear system model we systematically calculate the evaporation residue cross sections (ERCSs) of superheavy nuclei (SHN) for the ⁴⁸Ca-induced hot fusion reactions. Different calculations of the fission barriers of the SHN are used. The difference is as large as two orders of magnitude of ERCSs by applying the various fission barriers for the reaction ⁴⁸Ca+²⁴⁹Cf. The dependence of the calculated ERCSs on the predicted shell structure and magic numbers of the heavier SHN is discussed. It is found that the structure of SHN crucially influences the ERCSs. Measurement of ERCSs for at least one isotope of the $Z\,\gt 118$ nucleus would help us to set a proper shell model for the SHN with $Z\,\gt$ 118.

We propose to use two-body regularized finite-range pseudopotential to generate nuclear energy density functional (EDF) in both particle–hole and particle–particle channels, which makes it free from self-interaction and self-pairing, and also free from singularities when used beyond mean field. We derive a sequence of pseudopotentials regularized up to next-to-leading order and next-to-next-to-leading order, which fairly well describe infinite-nuclear-matter properties and finite open-shell paired and/or deformed nuclei. Since pure two-body pseudopotentials cannot generate sufficiently large effective mass, the obtained solutions constitute a preliminary step towards future implementations, which will include, e.g., EDF terms generated by three-body pseudopotentials.

We explore the applicability of the differential evolution algorithm in finding the global minima of three typical nuclear structure physics problems: the global deformation minimum in the nuclear potential energy surface, the optimization of mass model parameters and the lowest eigenvalue of a nuclear Hamiltonian. The algorithm works very effectively and efficiently in identifying the minima in all problems we have tested. We also show that the algorithm can be parallelized in a straightforward way.

The importance of the saturation effect of cold nuclear matter (NM) on describing the fusion hindrance phenomenon at extremely low incident energies is investigated for the medium-heavy mass system of ⁵⁸Ni+⁵⁴Fe. From the theoretical viewpoint, for considering the mentioned property during the fusion process one can use the double-folding (DF) model which is modified through the repulsive core effects as a basic heavy ion–ion potential. The theoretical calculations of the fusion cross sections are performed using the coupled-channel technique, including couplings to the low-lying ${2}^{+}$ and ${3}^{-}$ states in target and projectile. It is shown that the corrective effects of the cold NM provide an appropriate description for the energy-dependent behavior of the measured fusion cross sections at extremely low incident energies. Moreover, we find that the calculated results of the astrophysical S factor and the logarithmic derivative based on the modified form of the DF model are in good agreement with the corresponding experimental data at these energies. A discussion is also presented about the predictions of the present sudden approach for the behavior of the fusion cross sections at high incident energies. The obtained results reveal that this behavior depends on the nuclear structure of the reacting nuclei.

A study of elliptic flow of open charm mesons, D⁰ and ${D}_{S}^{\pm }$, using quark coalescence as a mechanism of hadronization of heavy quarks implemented in conjunction with A Multi-Phase Transport model has been presented. We have studied the transverse momentum dependence of the elliptic flow parameter at mid-rapidity ($| y|$ < 1.0) for Au+Au collisions at $\sqrt{{s}_{{\rm{NN}}}}=200\,\mathrm{GeV}$ (RHIC) and Pb+Pb collisions at $\sqrt{{s}_{{\rm{NN}}}}=2.76$ TeV (LHC) for different values of partonic interaction cross-section and QCD coupling constant. We have compared our calculations with the experimentally measured data at the LHC energy. We have also studied the effect of shear viscosity on elliptic flow of open charm mesons within the transport model approach. Our study indicates that the elliptic flow of open charmed mesons is more sensitive to the viscous properties of the quark–gluon plasma medium as compared to light charged hadrons.

Resorting to a neural network approach we refined several representative and sophisticated global nuclear mass models within the latest atomic mass evaluation (AME2012). In the training process, a quite robust algorithm named the Levenberg–Marquardt (LM) method is employed to determine the weights and biases of the neural network. As a result, this LM neural network approach demonstrates a very useful tool for further improving the accuracy of mass models. For a simple liquid drop formula the root mean square (rms) deviation between the predictions and the 2353 experimental known masses are sharply reduced from 2.455 MeV to 0.235 MeV, and for the other revisited mass models, the rms is remarkably improved by about 30%.

We study the nuclear medium effects in Drell–Yan process using quark parton distribution functions calculated in a microscopic nuclear model which takes into account the effects of Fermi motion, nuclear binding and nucleon correlations through a relativistic nucleon spectral function. The contributions of π and ρ mesons as well as shadowing effects are also included. The beam energy loss is calculated using a phenomenological approach. The present theoretical results are compared with the experimental results of the E772 and E866 experiments. These results are applicable to the forthcoming experimental analysis of E906 Sea Quest experiment at the Fermi Lab.

We evaluate the total cross section for the π-photoproduction process and analyze the behavior of the ${\rm{\Delta }}(1232)$ resonance contribution when the photon energy is increased from threshold up to 0.7 GeV. Within this energy range we compare two different parameterizations for the $\gamma N{\rm{\Delta }}$ vertex: the normal parity and the covariant multipole decomposition ones. For completeness, we also compare different versions for the Δ propagator: the first is the dressed propagator obtained including one-loop self-energy contributions (EXACT), the second is the complex mass scheme which consists in replacing ${{m}}_{{\rm{\Delta }}}\to {{m}}_{{\rm{\Delta }}}-{\rm{i}}{{\rm{\Gamma }}}_{{\rm{\Delta }}}/2$ in the bare propagator, and the third is an intermediate approximation between the two previous ones (EXCMS). We conclude that, in order to extend the present calculation to include more energetic resonances in the future and to obtain non-divergent results for the total cross section we will need to use the MD parametrization and the EXCMS propagator.

Background. According to standard stellar evolution, lithium abundance is believed to be a useful indicator of the stellar age. However, many evolved stars like red giants show huge fluctuations around expected theoretical abundances that are not yet fully understood. The better knowledge of nuclear reactions that contribute to the creation and destruction of lithium can help to solve this puzzle. Purpose. In this work we apply the Gamow shell model formulated in the coupled-channel representation to investigate the mirror radiative capture reactions ⁶Li(p, γ)⁷Be and ⁶Li(n, γ)⁷Li. Method. The cross-sections are calculated using a translationally invariant Hamiltonian with the finite-range interaction which is adjusted to reproduce spectra, binding energies and one-nucleon separation energies in ^6–7Li, ⁷Be. The reaction channels are built by coupling the wave functions of ground state ${1}_{1}^{+}$ and excited states ${3}_{1}^{+}$, ${0}_{1}^{+}$, ${2}_{1}^{+}$ of ⁶Li with the projectile wave function in different partial waves. Results. We include all relevant E1, M1, and E2 transitions from the initial continuum states to the final bound states $J=3/{2}_{1}^{-}$ and $J=1/{2}^{-}$ of ⁷Li and ⁷Be. Our microscopic astrophysical factor for the ⁶Li(p, γ)⁷Be reaction follows the average trend of the experimental value as a function of the center of mass energy. For ${}^{6}\mathrm{Li}(n,\gamma ){}^{7}\mathrm{Li}$, the calculated cross section agrees well with the data from the direct measurement of this reaction at stellar energies. Conclusion. We demonstrate that the s-wave radiative capture of proton (neutron) to the first excited state ${J}^{\pi }=1/{2}_{1}^{+}$ of ⁷Be (⁷Li) is crucial and increases the total astrophysical S-factor by about 40%.

A consistent model for the description of suprathermal processes in the solar core plasma naturally triggered by fast particles generated in exoergic nuclear reactions is formulated. This model, based on the formalism of in-flight reaction probability, operates with different methods of treating particle slow-down in the plasma, and allows for the influence of electron degeneracy and electron screening on processes in the matter. The model is applied to examine slowing-down of 8.7 MeV α-particles produced in the ${}^{7}\mathrm{Li}(p,\alpha )\alpha$ reaction of the pp chain, and to analyze suprathermal processes in the solar CNO cycle induced by them. Particular attention is paid to the suprathermal ${}^{14}{\rm{N}}{(\alpha ,{\rm{p}})}^{17}{\rm{O}}$ reaction unappreciated in standard solar model simulations. It is found that an appreciable non-standard $(\alpha ,p)$ nuclear flow due to this reaction appears in the matter and modifies running of the CNO cycle in ∼95% of the solar core region. In this region at $R\gt 0.1{R}_{\odot }$, normal branching of nuclear flow ${}^{14}{\rm{N}}\leftarrow {}^{17}{\rm{O}}\to {(}^{18}{\rm{F}})\to {}^{18}{\rm{O}}$ transforms to abnormal sequential flow ${}^{14}{\rm{N}}\to {}^{17}{\rm{O}}\to {(}^{18}{\rm{F}})\to {}^{18}{\rm{O}}$, altering some element abundances. In particular, nuclear network calculations reveal that in the outer core the abundances of ¹⁷O and ¹⁸O isotopes can increase by a factor of 20 as compared with standard estimates. A conjecture is made that other CNO suprathermal $(\alpha ,p)$ reactions may also affect abundances of CNO elements, including those generating solar neutrinos.