The properties of the nuclear isoscaling at finite temperature are investigated and the extent to which its parameter $α$ holds information on the symmetry energy is examined. We show that, although finite temperature effects invalidate the analytical formulas that relate the isoscaling parameter $α$ to those of the mass formula, the symmetry energy remains the main ingredient that dictates the behavior of $α$ at finite temperatures, even for very different sources. This conclusion is not obvious as it is not true in the vanishing temperature limit, where analytical formulas are available. Our results also reveal that different statistical ensembles lead to essentially the same conclusions based on the isoscaling analysis, for the temperatures usually assumed in theoretical calculations in the nuclear multifragmentation process.
Using different parameterizations of the nuclear mass formula, we study the sensitivity of the isoscaling parameters to the mass formula employed in grand-canonical calculations. Previous works on isoscaling have suggested that the symmetry energy implied in such calculations is anomalously smaller than that suggested by fits to nuclear masses. We show that surface corrections to the symmetry energy naturally broadens the isotopic distribution thus allowing for values of the symmetry energy which more closely match those obtained from nuclear masses.
Isoscaling and isobaric yield ratio parameters are compared from canonical and grand canonical ensembles when applied to multifragmentation of finite nuclei. Source dependence of isoscaling parameters and source and isospin dependence of isobaric yield ratio parameters are examined in the framework of the canonical and the grand canonical models. It is found that as the nucleus fragments more, results from both the ensembles converge and observables calculated from the canonical ensemble coincide more with those obtained from the formulae derived using the grand canonical ensemble.
Experiments with rare isotopes are shedding light on the role isospin plays in the equation of state (EoS) of nuclear matter, and isoscaling -an straight-forward comparison of reactions with different isospin- could deliver valuable information about it. In this work we test this assertion pragmatically by comparing molecular dynamics simulations of isoscaling reactions using different equations of state and looking for changes in the isoscaling parameters; to explore the possibility of isoscaling carrying information from the hot-and-dense stage of the reaction, we perform our study in confin…
We show that the qualitative behavior of the nuclear caloric curve can be inferred from the energy dependence of the isoscaling parameters. Since there are strong indications that the latter are not distorted by the secondary decay of primary hot fragments, in contrast to other observables, this suggests that valuable information on the nuclear caloric curve may be obtained through the analysis presented in this work.
This study shows that isoscaling, usually studied in nuclear reactions, is a phenomenon common to all cases of fair sampling. Exact expressions for the yield ratio $R_{21}$ and approximate expressions for the isoscaling parameters $α$ and $β$ are obtained and compared to experimental results. It is concluded that nuclear isoscaling is bound to contain a component due to sampling and, thus, a words of caution is issued to those interested in extracting information about the nuclear equation of state from isoscaling.
Isoscaling is found to hold for fragment yields in the antisymmetrized molecular dynamics (AMD) simulations for collisions of calcium isotopes at 35 MeV/nucleon. This suggests the applicability of statistical considerations to the dynamical fragment emission. The observed linear relationship between the isoscaling parameters and the isospin asymmetry of fragments supports the above suggestion. The slope of this linear function yields information about the symmetry energy in low density region where multifragmentation occurs.
The symmetry energy, temperature, density and isoscaling parameter, in $^{58}$Ni + $^{58}$Ni, $^{58}$Fe + $^{58}$Ni and $^{58}$Fe + $^{58}$Fe reactions at beam energies of 30, 40 and 47 MeV/nucleon, are studied as a function of excitation energy of the multifragmenting source. It is shown that the decrease in the isoscaling parameter is related to the near flattening of the temperature in the caloric curve, and the decrease in the density and the symmetry energy with increasing excitation energy. The decrease in the symmetry energy is mainly a consequence of decreasing density with increasing …
The isospin effect and isoscaling behavior in projectile fragmentation have been systematically investigated by a modified statistical abrasion-ablation (SAA) model. The normalized peak differences and reduced isoscaling parameters are found to decrease with ($Z_{proj}-Z$)/$Z_{proj}$ or the excitation energy per nucleon and have no significant dependence on the size of reaction systems. Assuming a Fermi-gas behavior, the excitation energy dependence of the symmetry energy coefficients are tentatively extracted from $α$ and $β$ which looks consistent with the experimental data. It is pointed ou…
Investigation of observables from nuclear multifragmentation reactions depending on isospin led to the development of a hybrid model. The mass and charge distribution as well as isotopic distribution was studied using this model for $^{112}$Sn+$^{112}$Sn reaction as well as $^{124}$Sn+$^{124}$Sn reactions at different energies. The agreement of the results obtained from the model with those from experimental data confirms the accuracy of the model. Isoscaling coefficients were extracted from these observables which can throw light on the symmetry energy coefficient. Another important facet of …
In the framework of the Statistical Multifragmentation Model, the nuclear isoscaling analysis is extended to constrain the ratio between the sizes of the decaying sources formed in a collision between two heavy ions. It is found that the ratio between the probabilities of observing n fragments in each event, for each of the sources, follows a scaling law, similar to the traditional nuclear isoscaling. However, the corresponding slope is also sensitive to the sources' sizes. This property is explained analytically using the grand-canonical ensemble. The extent to which our findings are affected…
Extensive calculations on isoscaling behavior with the sequential-decay model gemini are performed for the medium-to-heavy nuclei in the mass range A = 60-120 at excitation energies up to 3 MeV/nucleon. The comparison between the products after the first-step decay and the ones after the entire-steps decay demonstrates that there exists a strong sequential decay effect on the final isoscaling parameters and the apparent temperature. Results show that the apparent symmetry energy coefficient $γ_{app}$ does not reflect the initial symmetry energy coefficient $C_{sym}$ embedded in the mass calcul…
The energetic properties of nuclear clusters inside a low-density, finite-temperature medium are studied with a Lattice Gas Model including isospin dependence and Coulomb forces. Important deviations are observed respect to the Fisher approximation of an ideal gas of non-interacting clusters, but the global energetics can still be approximately expressed in terms of a simple modified energy-density functional. The multi-fragmentation regime appears dominated by combinatorial effects in this model, but the isoscaling of the largest fragment in low energy collisions appears a promising observabl…
Based on an extended compound nucleus model, isospin effects in statistical fragment emission from excited nuclear systems are investigated. An experimentally observed scaling behavior of the ratio of isotope yields $Y_i(N,Z)$ from two similar emitting sources with different neutron-to-proton ratios is predicted theoretically, i.e., the relationship of $Y_2/Y_1 \propto exp(αN + βZ)$ is demonstrated. The symmetry energy coefficient $C_{sym}$ extracted from the simulation results is $\sim$ 27 MeV which is consistent with realistic theoretical estimates and recent experimental data. The influence…
The isoscaling behavior is investigated in the frame of Isospin dependent Quantum Molecular Dynamics (IQMD) models. The isotopic yields ratio $Y_2$/$Y_1$ for reactions $^{48}Ca$+$^{48}Ca$ and $^{40}Ca+^{40}Ca$ at different entrance channels are simulated and presented, the relationship between the isoscaling parameter and the entrance channel is analyzed, the results show that $α$ and $β$ reduce with the rise of incident energies and increase with the impact parameter b, which can be attributed to the temperature varying of the pre-fragments in different entrance channels. The relation of $α$ …
Isotopic effects observed in fragmentation reactions induced by protons, deuterons, and alpha particles of incident energies between 660 MeV and 15.3 GeV on 112-Sn and 124-Sn targets are discussed. The exponential scaling of the yield ratios with the third component of the fragment isospin (N-Z)/2 is observed in all reactions, with scaling parameters that depend on the incident energy. Breakup temperatures for these reactions are deduced from double ratios of isotopic yields and tested for their relation with the isoscaling parameters. The quantum statistical (QSM) and the statistical multifra…
The projectile fragmentation reactions using $^{58}Ni$ $\&$ $^{64}Ni$ beams at 140 MeV/n on targets$^{9}Be$ $\&$ $^{181}Ta$ are studied using the canonical thermodynamical model coupled with an evaporation code. The isoscaling property of the fragments produced is studied using both the primary and the secondary fragments and it is observed that the secondary fragments also respect isoscaling though the isoscaling parameters $α$ and $β$ changes. The temperature needed to reproduce experimental data with the secondary fragments is less than that needed with the primary ones. The canonical model…
A new method of accessing information on the symmetry free energy from yields of fragments produced in Fermi-energy heavy-ion collisions is proposed. Furthermore, by means of quantum fluctuation analysis techniques, correlations between extracted symmetry free-energy coefficients with temperature and density were studied. The obtained results are consistent with those of commonly used isoscaling techniques.
Isoscaling behavior of the statistical emission fragments from the equilibrated sources with $Z$ = 30 and $N$ = 30, 33, 36 and 39, resepectively, is investigated in the framework of isospin dependent lattice gas model. The dependences of isoscaling parameters $α$ on source isospin asymmetry, temperature and freeze-out density are studied and the "symmetry energy" is deduced from isoscaling parameters. Results show that "symmetry energy" $C_{sym}$ is insensitive to the change of temperature but follows the power-law dependence on the freeze-out density $ρ$. The later gives $C_{sym}$ = 30$(ρ/ρ_0…
The density dependence of the symmetry energy in the equation of state of isospin asymmetric nuclear matter is of significant importance for studying the structure of systems as diverse as the neutron-rich nuclei and the neutron stars. A number of reactions using the dynamical and the statistical models of multifragmentation, and the experimental isoscaling observable, is studied to extract information on the density dependence of the symmetry energy. It is observed that the dynamical and the statistical model calculations give consistent results assuming the sequential decay effect in dynamic…
It is shown that the experimentally observed decrease of the nuclear symmetry energy with the increasing centrality or the excitation energy in isotopic scaling analyses of heavy-ion reactions can be well understood analytically within a degenerate Fermi gas model. The evolution of the symmetry energy is found to be mainly due to the variation in the freeze-out density rather than temperature. The isoscaling analyses are useful for probing the interaction part of the nuclear symmetry energy, provided that both the freeze-out temperature and density of the fragments can be inferred simultaneous…
The density dependence of the symmetry energy in the equation of state of isospin asymmetric nuclear matter is studied using the isoscaling of the fragment yields and the antisymmetrized molecular dynamic calculation. It is observed that the experimental data at low densities are consistent with the form of symmetry energy,E$_{sym}$ $\approx$ 31.6 ($ρ/ρ_{\circ})^{0.69}$, in close agreement with those predicted by the results of variational many-body calculation. A comparison of the present result with those reported recently using the NSCL-MSU data suggests that the heavy ion studies favor a d…
The density dependence of the nuclear symmetry energy is inspected using the Statistical Multifragmentation Model with Skyrme effective interactions. The model consistently considers the expansion of the fragments' volumes at finite temperature at the freeze-out stage. By selecting parameterizations of the Skyrme force that lead to very different equations of state for the symmetry energy, we investigate the sensitivity of different observables to the properties of the effective forces. Our results suggest that, in spite of being sensitive to the thermal dilation of the fragments' volumes, it …
The antisymmetrized molecular dynamics (AMD) simulations suggest that the isospin composition of fragments produced dynamically in multifragmentation reactions is basically governed by the symmetry energy of low-density uniform nuclear matter rather than the symmetry energy for the ground-state finite nuclei. After the statistical secondary decay of the excited fragments, the symmetry energy effect still remains in the fragment isospin composition, though the effect in the isoscaling parameter seems a very delicate problem.
A thermal extension of the relativistic nuclear field theory is formulated for the nuclear response. The Bethe-Salpeter equation (BSE) with the time-dependent kernel for the particle-hole response is treated within the Matsubara Green's function formalism. We show that, with the help of a temperature-dependent projection operator on the subspace of the imaginary time (time blocking), it is possible to reduce the BSE for the nuclear response function to a single frequency variable equation also at finite temperature. The approach is implemented self-consistently in the framework of quantum hadr…
We present, for the first time, simultaneous determination of shear viscosity ($η$) and entropy density ($s$) and thus, $η/s$ for equilibrated nuclear systems from $A$ $\sim$ 30 to $A$ $\sim$ 208 at different temperatures. At finite temperature, $η$ is estimated by utilizing the $γ$ decay of the isovector giant dipole resonance populated via fusion evaporation reaction, while $s$ is evaluated from the nuclear level density parameter (${a}$) and nuclear temperature ($T$), determined precisely by the simultaneous measurements of the evaporated neutron energy spectra and the compound nuclear angu…
Neutron Skin Effects on Particle Emission in Heavy-Ion Collisions: A Topic Review with Astrophysical and Nuclear Structure Connections
Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Institute of Modern Physics, Fudan University(复旦大学现代物理研究所);Shanghai Research Center for Theoretical Nuclear Physics, NSFC and Fudan University(复旦大学理论核物理上海研究中心);School of Physics, East China Normal University(华东师范大学物理系)
We study the fermionic Matsubara Green functions in medium-mass nuclei at finite temperature. The single-fermion Dyson equation with the dynamical kernel of the particle-vibration-coupling (PVC) origin is formulated and solved in the basis of Dirac spinors, which minimize the grand canonical potential with the meson-nucleon covariant energy density functional. The PVC correlations beyond mean field are taken into account in the leading approximation for the energy-dependent self-energy, and the full solution of the finite-temperature Dyson equation is obtained for the fermionic propagators. Wi…
Using covariance analysis, we quantify the correlations between the interaction parameters in a transport model and the observables commonly used to extract information of the Equation of State of Asymmetric Nuclear Matter in experiments. By simulating $^{124}$Sn+$^{124}$Sn, $^{124}$Sn+$^{112}$Sn and $^{112}$Sn+$^{112}$Sn reactions at beam energies of 50 and 120 MeV per nucleon, we have identified that the nucleon effective mass splitting are most strongly correlated to the neutrons and protons yield ratios with high kinetic energy from central collisions especially at high incident energy. Th…
The fragment production in multifragmentation of finite nuclei is affected by the critical temperature of nuclear matter. We show that this temperature can be determined on the basis of the statistical multifragmentation model (SMM) by analyzing the evolution of fragment distributions with the excitation energy. This method can reveal a decrease of the critical temperature that, e.g., is expected for neutron-rich matter. The influence of isospin on fragment distributions is also discussed.
The event-by-event p_T-fluctuations due to the temperature variation are considered. The so-called Phi-measure is computed and shown to be a linear function of the temperature variance. The fluctuations of temperature naturally explain the data on Phi(p_T) in proton-proton and central Pb-Pb collisions but independent measurements of the temperature fluctuations are needed to confirm the explanation. Feasibility of such an event-by-event measurement is discussed.
The spin and parity dependent nuclear level densities (NLD) are calculated for medium-heavy nuclei using shell model techniques. The NLD are used to calculate cross sections and reaction rates of interest for nuclear astrophysics and nuclear energy applications. We investigate a new approach of describing the shell model NLD via a constant temperature parametrization. This approach provides new information about the effects of symmetries on the temperature of the low-lying nuclear states, and it is shown to be more versatile for applications.
The understanding of the interaction of nucleons in nuclear and neutron-rich matter at non-zero temperature is important for a variety of applications ranging from heavy-ion collisions to nuclear astrophysics. In this paper we apply the Dirac-Brueckner-Hartree-Fock method along with the Bonn B nucleon-nucleon potential to predict single-particle properties in symmetric nuclear matter and pure neutron matter at finite temperature. It is found that temperature effects are generally small but can be significant at low density and momentum.
We study here the equation of state of symmetric nuclear matter at finite temperatures using a modified SU(2) Chiral Sigma model. The effect of temperature on effective mass, pressure, entropy and binding energy is discussed. The liquid-gas phase transition is investigated and the critical values of temperature, density and pressure are calculated.
We calculate the equation of state of asymmetric nuclear matter at finite temperature based on chiral effective field theory interactions to next-to-next-to-next-to-leading order. Our results assess the theoretical uncertainties from the many-body calculation and the chiral expansion. Using a Gaussian process emulator for the free energy, we derive the thermodynamic properties of matter through consistent derivatives and use the Gaussian process to access arbitrary proton fraction and temperature. This enables a first nonparametric calculation of the equation of state in beta equilibrium, and …
Based on recent studies of the temperature dependence of the energy and specific heat of liquid nuclear matter, a phase transition is suggested at a temperature $\sim .8$ MeV. We apply Landau Ginzburg theory to this transition and determine the behaviour of the energy and specific heat close to the critical temperature in the condensed phase.
The nucleon spectral function in nuclear matter fulfills an energy weighted sum rule. Comparing two different realistic potential, these sum rules are studied for Green's functions that are derived self-consistently within the $T$ matrix approximation at finite temperature.
A study of the correlation between nuclear temperatures and symmetry energy is presented for heavy-ion collisions at intermediate energies via the isospin-dependent quantum molecular-dynamics model. It is found that different symmetry energy parameters will change the density and kinetic energy distribution of the hot nuclei. More importantly, nuclear temperatures that are based on kinetic energy properties can be used to study symmetry energy information.
The temperature dependence of the nuclear matter isovector symmetry energy coefficient ($\cA_{0,1}$) is investigated in the framework of the generalized nuclear polarizability with Skyrme interactions, as worked out in Refs. \cite{npa,prc}. The variation of $\cA_{0,1}(T)$ is very small (of the order of 1 MeV) for temperatures (T) in the range of 0 and 18 MeV. Different behaviors with temperature are found strongly depending on the Skyrme parameterization, in particular at densities lower than the saturation density $ρ_0$.
The dipole response function of nuclear matter at zero and finite temperatures is investigated by employing the linearized version of the extended TDHF theory with a non-Markovian binary collision term. Calculations are carried out for nuclear dipole vibrations by employing the Steinwedel-Jensen model and compared with experimental results for $^{120}Sn$ and $^{208}Pb$.
In high-energy nuclear collisions, heavy quark potential at finite temperature controls the quarkonium production. Including the relaxation of the medium induced by the relative velocity between quarkonia and the deconfined expanding matter, the Debye screening is reduced and the quarkonium dissociation takes place at a higher temperature. As a consequence of the velocity dependent dissociation temperature, the quarkonium suppression at high transverse momentum is significantly weakened in high energy nuclear collisions at RHIC and LHC.
A self-consistent approach based on finite temperature Green's functions is used to investigate thermodynamic properties of nuclear matter. The internal energy is derived from the diagrams associated to the interaction energy. Pressure and entropy up to T=20 MeV are obtained from the generating functional form of the thermodynamic potential.
A microscopic nuclear equation of state compatible with all current astrophysical constraints constructed within the Brueckner-Hartree-Fock formalism is presented and extended in a consistent way to finite temperature. The effects of finite temperature on the properties of neutron stars are studied in detail and a universal relation regarding stellar stability is proposed.
The description of collective motion in nuclei at finite temperature using the framework of the random phase approximation is discussed. We focus on the special case of the isovector response function of hot nuclear matter using various effective Skyrme interactions.
With the effective chiral model, the finite temperature properties of nuclear matter have been studied at different temperatures. For symmetric nuclear matter, I particularly focused on the possibility of liquid-gas phase transition at low temperature and density. The critical temperature obtained in this context, is consistent with the experimental and empirical findings. The free energy and entropy variations are also studied for different values of temperature. A few asymmetric nuclear matter properties like the equation of state and the speed of sound with respect to temperature are also e…
We study isovector collective excitations in nuclear matter by employing the linearized Landau-Vlasov equation with and without a non-Markovian binary collision term at finite temperature. We calculate the giant dipole resonance (GDR) strength function for finite nuclei using Steinwedel-Jensen model and also by Thomas-Fermi approximation, and we compare them for 120Sn and 208Pb with experimental results.
We consider the propagation and damping of isovector excitations in heated nuclear matter within the Landau Fermi-liquid theory. Results obtained for nuclear matter are applied to calculate the Giant Dipole Resonance (GDR) at finite temperature in heavy spherical nuclei within Steinwedel and Jensen model. The centroid energy of the GDR slightly decreases with increasing temperature and the width increases as $T^2$ for temperatures $T < 5$ MeV in agreement with recent experimental data for GDR in $^{208}$Pb and $^{120}$Sn. The validity of the method for other Fermi fluids is finally suggested.
Effects of energy dissipation on quantum nucleation of two-flavor quark matter in dense nuclear matter encountered in neutron star cores are examined at low temperatures. We find that low-energy excitations of nucleons and electrons reduce the nucleation rate exponentially via their collisions with the surface of a quark matter droplet.
In this paper we present a study of in-medium jet modifications performed with JEWEL and PYTHIA 6.4, focusing on the uncertainties related to variations of the perturbative scales and nuclear parton distribution functions (PDFs) and on the impact of the initial and crossover temperature variations of the medium. The simulations are compared to LHC data for the jet spectrum and the nuclear modification factor. We assess the interplay between the choice of nuclear PDFs and different medium parameters and study the impact of nuclear PDFs and the medium on the jet structure via the Lund plane.
We develop a nonperturbative technique in field theory to study properties of infinite nuclear matter at zero temperature as well as at finite temperatures. Here we dress the nuclear matter with off-mass shell pions. The techniques of thermofield dynamics are used for finite temperature calculations. Equation of state is derived from the dynamics of the interacting system in a self consistent manner. The transition temperature for nuclear matter appears to be around 15 MeV.
We compute the free energy of asymmetric nuclear matter in a Brueckner-Hartree-Fock approach at finite temperature, paying particular attention to the dependence on isospin asymmetry. The first- and second-order symmetry energies are determined as functions of density and temperature and useful parametrizations are provided. We find small deviations from the quadratic isospin dependence and very small corresponding effects on (proto)neutron star structure.
The density and temperature dependence of nucleonic single particle spectral function in symmetric nuclear matter at finite temperatures and densities beyond normal nuclear matter density is investigated in a model emphasizing short-range correlations and phase space aspects. A simple but self-consistent approach based on quantum transport theory is used. In particular we consider the density and temperature regime occuring e.g. during the core collapse in a supernova explosion and the subsequent formation of a neutron star. Mean-field effects are incorporated by a Skyrme type potential.
Based on the formalism of thermo-field dynamics a new approach for studying collective excitations in hot finite Fermi systems is presented. Two approximations going beyond the thermal RPA namely renormalized thermal RPA and thermal second RPA are formulated.
A systematic comparison of different isotopic temperatures with the thermodynamical temperature of a multifragment system is made on the basis of the Statistical Multifragmentation Model. It is demonstrated that isotopic temperatures are strongly affected by the secondary decays of hot primary fragments and the population of particle-stable excited states in final fragments. The He-Li temperatures, measured recently by the ALADIN group, are reproduced fairly well both as a function of excitation energy and bound charge. Our analysis confirms the anomaly in the nuclear caloric curve.
The agreement between the fragments' internal and kinetic temperatures with the breakup temperature is investigated using a Statistical Multifragmentation Model which makes no a priori as- sumption on the relationship between them. We thus examine the conditions for obtaining such agreement and find that, in the framework of our model, this holds only in a relatively narrow range of excitation energy. The role played by the qualitative shape of the fragments' state densities is also examined. Our results suggest that the internal temperature of the light fragments may be affected by this quant…
The relation between collective modes and the phase transition in low density nuclear matter is examined. The dispersion relations for collective modes in a linear approach are evaluated within a Landau-Fermi liquid scheme by assuming coexisting phases in thermodynamical equilibrium. Temperature and isospin composition are taken as relevant parameters. The in-medium nuclear interaction is taken from a recently proposed density functional model. We found significative modifications in the energy spectrum, within certain range of temperatures and isospin asymmetry, due to the separation of matte…
The nuclear collective response at finite temperature is investigated for the first time in the quantum framework of the small amplitude limit of the extended TDHF approach, including a non-Markovian collision term. It is shown that the collision width satisfies a secular equation. By employing a Skyrme force, the isoscalar monopole, isovector dipole and isoscalar quadrupole excitations in $^{40}Ca$ are calculated and important quantum features are pointed out. The collisional damping due to decay into incoherent 2p-2h states is small at low temperatures but increases rapidly at higher tempera…
The improved quark mass density-dependent (IQMDD) model, which has been successfully used to describe the properties of both infinite nuclear matter and finite nuclei, is applied to investigate the properties of quark deconfinement phase transition. By using the finite-temperature quantum field theory, we calculate the finite temperature effective potential and extend the IQMDD model to finite temperature and finite nuclear matter density. The critical temperature and the critical density of nuclear matter are given and the QCD phase diagram is addressed. It is shown that this model can not on…
We study symmetric nuclear matter at finite temperature, with particular emphasis on the liquid-gas phase transition. We use a standard covariance analysis to propagate statistical uncertainties from the density functional to the thermodynamic properties. We use four functionals with known covariance matrices to obtain as wide a set of results as possible. Our findings suggest that thermodynamical properties are very well constrained by fitting data at zero temperature. The propagated statistical errors in the liquid-gas phase transition parameters are relatively small.
We present a short overview of our recent theoretical developments aiming at the description of exotic nuclear phenomena to be reached and studied at the next-generation radioactive beam facilities. Applications to nuclear shell structure and response of nuclei at the limits of their existence, with a special focus on the physics cases of astrophysical importance, are discussed.