[en] The proceedings of the 20. International Nuclear Physics Divisional Conference of the European Physical Society covers a wide range of topics in nuclear astrophysics. The topics addressed are big bang nucleosynthesis, stellar nucleosynthesis, measurements and nuclear data for astrophysics, nuclear structure far from stability, neutrino physics, and rare-ion-beam facilities and experiments. The perspectives of nuclear physics and astrophysics are also overviewed. 77 items are indexed separately for the INIS database. (K.A.)

No abstract available

[en] The LUNA (Laboratory for Underground Nuclear Astrophysics) accelerator facilities installed at the Laboratori Nazionali del Gran Sasso, Italy offers unique possibilities for the studies of low cross section nuclear reactions owing to the extremely low cosmic background in the underground site. The experiments have been started at the recently installed and tested 400 kV accelerator (LUNA 2). Different solid state N targets were prepared and tested in order to find the optimal targets for the measurements. (R.P.)

[en] An overview is given on the experimental nuclear physics aspects of the astrophysical p-process that is responsible for the production of the heavy proton-rich nuclei known as p-nuclei. The nuclear physics input of the p-process scenario involves the knowledge of radiative capture cross sections, mostly calculated by the Hauser-Feshbach statistical model. Our experiments test the reliability of the model calculations in the proton-rich region as well as provide experimental information on the cross sections relevant to the p-process

[en] The underground accelerator facility LUNA2 installed at the Laboratori Nazionali del Gran Sasso has been used for studies of low cross section nuclear reactions of astrophysical interest, exploiting the strong suppression of cosmic background. The first reaction to be studied using solid state targets is the ¹⁴N(p,γ)¹⁵O reaction. In order to minimize the beam induced background, different target preparation procedures with different target backings have been used and the targets have been tested at the LUNA2 facility

[en] Complete text of publication follows. The astrophysical p-process, the production mechanism of the heavy proton rich isotopes (the so-called p-nuclei) is still one of the least understood processes of nucleosynthesis. The modeling of the process requires a huge network of thousands of reactions where the rates of the involved reactions represent one of the biggest uncertainty in the resulting abundances of p-nuclei. In lack of experimental data the required reaction rates are taken from statistical model calculations which proved to be inaccurate in the mass and energy range relevant for the p-process. The systematic experimental study of the relevant reactions is therefore crucial to test the calculated reaction rates, to select the best input parameters for the calculations and, consequently, to contribute to a better understanding of the astrophysical p-process. The European Research Council (ERC) has acknowledged this need for experimental data when they decided to support a project devoted to this subject. In 2007 the first call of the ERC Frontier Research Scheme (Starting Grants) has been launched within the FP7 Specific Programme 'IDEAS'. From the very high number of applications, the peer reviewers of the ERC Scientific Council has recommended for funding the proposal entitled 'Nuclear reaction studies relevant to the astrophysical p-process nucleosynthesis'. An amount of 750,000 Euro has been allocated to the project for a 5 year duration. The starting date of the project was 1st July, 2008. With the ERC support, an extensive experimental study of the p-process is being carried out. The experiments will be carried out almost exclusively with the accelerators of the ATOMKI. The financial support allows to largely improve the available experimental technique. The purchase of two large volume HPGe detectors is in progress as a result of a public procurement. The upgrade of the nuclear electronics and data acquisition system used for p-process related experiments has also been started. The particle beam selection and properties available in ATOMKI and the technical development provided by the ERC support will make it possible to extend substantially the experimental database relevant for the p-process. Proton as well as alpha induced reaction cross sections will be measured and compared with statistical model predictions. The completely unexplored higher mass region is hoped to be reached in the case of alpha capture reactions. The planned alpha elastic scattering experiments will contribute to the fine tuning of the statistical model calculations by probing one of its most important input parameters, the optical potential. With the planned experiments a significant improvement of the understanding of the p-process will be reached

[en] Compete text of publication follows. The satisfaction of the Newcomb-Benford law (a.k.a. Benford's first digit law) is a long standing issue in science, and has interesting mathematical and philosophical consequences. It was identified by Newcomb in 1881 and reinvented later by Benford in 1938. The law states that the distribution of the first digit of numbers taken from various sources like magazines, scientific publications, wealth statistics, etc. . . follows the law P_d = lg (1 + 1/d) (d = 1, 2, ..., 9), where d is the given digit. It was reported recently that the satisfaction of the law was observed in nuclear decay half-life datasets. Based on this fact, it was implied that the law is helpful as a test for nuclear decay models, as well as it can be used to search for new physical phenomena (like self organized criticality) which can be responsible for the satisfaction of the law. The mathematical conundrum of the Newcomb-Benford law has been solved in 2008 for numbers coming from a data set with a given distribution. The 'Benford compliance theorem' uses the Fourier transform of the probability distribution function of the numbers to identify the characteristics of the distribution responsible for the satisfaction of the law. In our work we confirmed that the halflives of radioactive nuclei satisfy the law by using two standard techniques: direct plotting and the 'ones scaling test' method. We also showed that the distribution of the half-life values closely resembles a log-normal distribution stretching through about 54 orders of magnitude. By using the Fourier transform of the distribution function we showed that the numbers with such a distribution automatically satisfy the Newcomb-Benford law, due to the compliance theorem. Thus we concluded that the satisfaction of the law provides no additional clue on whether a nuclear model is valid or not, given it produces a similar distribution of halflives as observed.

[en] Complete text of publication follows. The p-process nuclei are the proton-rich nuclides that are blocked from production in the r- and s-processes by stable nuclei. Calculation of the abundances of the p-process nuclides typically requires extensive numbers of reaction rates (many of which are either (p,γ) or (γ,p) reactions). Very few cross sections relevant to these processes, which involve light ions on relatively heavy nuclei, have been measured at energies appropriate to astrophysics, leaving these reaction networks dependent upon theoretical estimates calculated through statistical models. In our work we measured the (p,γ) reaction cross section of three Sr isotopes using activation technique. The targets consisted of SrF₂ layers evaporated onto carbon backing. Natural Sr was used which allowed us to determine the capture cross section of ⁸⁴Sr, ⁸⁶Sr and ⁸⁷Sr in a single activation measurement. After proton irradiation (which lasted between 6 and 24 hours) the gamma activity of the targets was measured with a high purity Ge detector. In case of ⁸⁴Sr and ⁸⁶Sr the cross section of proton capture leading both to the isomer and ground state of the corresponding Tc isotope could be determined. The investigated energy range between 1500 and 3000 keV was covered with 100 keV steps. The measurements were carried out with the 5 MV Van de Graaff accelerator of the ATOMKI. The data evaluations are in progress. As an example, the preliminary results concerning the ⁸⁶Sr(p,γ)⁸⁷Y^m reaction can be seen in Fig. 1. (author)

[en] Recently, the electron screening effect in d(d,p)t has been studied for the metals Al, Zr, and Ta, where the deuterated metals were produced via implantation of low-energy deuterons. This surprising result motivated the present systematic work. More than 25 deuterated metals and 15 insulators/semiconductors have been studied at the 100 kV accelerator of the Ruhr-Universitaet Bochum. (R.P.)

[en] The CNO cycle is one of the fundamental processes of hydrogen burning in stars. The first reaction of the cycle is the radiative proton capture on ${}^{12}$C and the rate of this ${}^{12}$C(p,γ)${}^{13}$N reaction is related to the ${}^{12}$C/${}^{13}$C ratio observed e.g. in the Solar System. The low-energy cross section of this reaction was measured several times in the past, however, the experimental data are scarce in a wide energy range especially around the resonance at 1.7 MeV. In the present work the ${}^{12}$C(p,γ)${}^{13}$N cross section was measured between 300 and 1900 keV using the activation method. This method was only used several decades ago in the low-energy region. As the activation method provides the total cross section and has uncertainties different from those of the in-beam γ-spectroscopy technique, the present results provide a largely independent data set for future low-energy extrapolations and thus for astrophysical reaction rate calculations.