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The mass and half-life of a nucleus are its basic properties which reflect its structure and decay properties. These data are among the most important nuclear physics inputs to astrophysical nucleosynthesis modelling. Tremendous experimental efforts are carried out to obtain yet unknown quantities, which are as a rule belong to short-lived nuclei far away from stability. Storage ring mass spectrometry is a technique ideally suited for addressing many different nuclear species at the same time. In the last few years it went through major developments regarding nuclear mass determinations, thereby boosting its efficiency, sensitivity and precision. A non-destructive detection capability is being presently implemented aiming at simultaneous mass, lifetime and decay branching measurements. Recent developments and future perspectives are briefly discussed.

Bound-state β−-decay is an exotic decay mode that produces temperature-dependent stability in nuclei. A striking example is 205Tl, in part because of its impact on the 205Pb/204Pb cosmochronometer—a short-lived ra-dionuclide clock that can provide unique constraints on s process material in the early solar system. The bound-state β−-decay of 205Tl was measured at GSI, where fully stripped 205Tl81+ ions were produced and stored in the Experimental Storage Ring. Decay occurred during storage producing increased 205Pb daughters with increased storage time. This contribution briefly outlines the experiment and describes analytical corrections required to extract the half-life.

We measured the Coulomb dissociation of 16O into 4He and 12C within the FAIR Phase-0 program at GSI Helmholtzzentrum für Schwerionenforschung Darmstadt, Germany. From this we will extract the photon dissociation cross section 16O(α,γ)12C, which is the time reversed reaction to 12C(α,γ)16O. With this indirect method, we aim to improve on the accuracy of the experimental data at lower energies than measured so far. The expected low cross section for the Coulomb dissociation reaction and close magnetic rigidity of beam and fragments demand a high precision measurement. Hence, new detector systems were built and radical changes to the R3B setup were necessary to cope with the high-intensity 16O beam. All tracking detectors were designed to let the unreacted 16O ions pass, while detecting the 12C and 4He.

The work presents the results of studying the content of potentially toxic elements (Mn, Cu, Zn, Cr, Pb, Ni and Cd) in bottom sediments sampled at monitoring stations in the natural-anthropogenic systems of the Lower Don adjacent to the impact zone of the Novocherkassk Power Plant. The relationship between the content of metals in bottom sediments and their sorption properties is largely determined by the conditions of formation and the type of bottom sediments. Evaluation of the potentially toxic element content in sediments indicated that in particle size fractions (≤ 0.001 mm) could accumulate more than 15 times the levels of Cr and Zn and more than 6 times the levels of Cu, Cd and Ni in comparison to the particle size fractions that are 1.0 mm. Local zones of polyelemental pollution of bottom sediments with respect to Cu, Zn, Pb Cd and Cr were determined. These zones are confined to the geochemical sorption barriers of small watercourses of the power plant.

The regularities of the accumulation and distribution of metals (Zn and Cd) in various parts of wild herbaceous plants and the agricultural crop of the impact zone in Rostov region (Russia) was considered. A large accumulation of elements in wild herbaceous plants of the Asteraceae family was noted compared with Triticum aestivum. The pollution of Triticum aestivum by Cd was observed. Wild herbaceous plants of the Asteraceae family were contaminated mostly with Zn. It was found that Artemisia austriaca and Ambrosia artemisiifolia accumulated Zn and Cd in the aboveground part. Achillea nobilis accumulated Cd mainly in the root system. Closer location monitoring plots to the source of anthropogenic load and the location of the northwest winds prevailing in the region were main influencing factors leading to higher pollution.

Based on the cumulative pollution index, spatial distribution maps were obtained to establish categories of soil pollution taking into account the total content of heavy metals and the mobile forms of metals in the Don River estuarine region. The objects of the study included samples of zonal soils (Chernozem) and intrazonal soils (Fluvisols) from monitoring plots. The total concentrations of Mn, Cr, Ni, Cu, Zn, Pb, and Cd in the soils were determined by X-ray fluorescent scanning spectrometer. Mobile heavy metals compounds were transferred to a solution by extraction of 1 N NH4Ac, pH 4.8. When calculating the total metal content, it was shown the studied soils had generally an acceptable pollution category but taking into account mobile forms the categories of soils contamination variate up acceptable to extremely dangerous. The most polluted sites are associated with the estuary of small rivers and the branches flowing into the Taganrog Bay, the territory of the Taganrog port and its terminals, and road bridges. In line with hight categories of pollution, the use of the soils for cropping should be limited, and the cultivation of concentrator plants is excluded.

Ion optical calculations for a storage ring at the present GSI facility for direct proton-induced reactions relevant for different astrophysical processes are presented. As an example case, the 59Cu(p,γ) and 59Cu(p,α) reactions are shown. The branching of these two reactions is important in X-ray burst scenarios, since it determines the breakout out of the major 56Ni waiting point.

The huge neutron fluxes offer the possibility to use research reactors to produce isotopes of interest, which can be investigated afterwards. An example is the half-lives of long-lived isotopes like 129I. A direct usage of reactor neutrons in the astrophysical energy regime is only possible, if the corresponding ions are not at rest in the laboratory frame. The combination of an ion storage ring with a reactor and a neutron guide could open the path to direct measurements of neutron-induced cross sections on short-lived radioactive isotopes in the astrophysically interesting energy regime.

Neutron capture cross sections of unstable isotopes are important for neutron-induced nucleosynthesis as well as for technological applications. A combination of a radioactive beam facility, an ion storage ring and a high flux reactor would allow a direct measurement of neutron induced reactions over a wide energy range on isotopes with half lives down to minutes. The idea is to measure neutron-induced reactions on radioactive ions in inverse kinematics. This means, the radioactive ions will pass through a neutron target. In order to efficiently use the rare nuclides as well as to enhance the luminosity, the exotic nuclides can be stored in an ion storage ring. The neutron target can be the core of a research reactor, where one of the central fuel elements is replaced by the evacuated beam pipe of the storage ring. Using particle detectors and Schottky spectroscopy, most of the important neutron-induced reactions, such as (n,γ), (n,p), (n,α), (n,2n), or (n,f), could be investigated.

Ten different theoretical models are tested for their accuracy in description of nuclear masses. Recent experimental masses of 2011 are used for the tests. The accuracy is studied in three regions of the nuclear chart: global (all nuclei with Z; N ≥ 8), heavy (Z ≥ 82; N ≥ 126) and the heaviest ones (Z > 100). It is found that the accuracy of a given model strongly depends on the region of nuclei in which it is used.