[en] The construction of the European Spallation Source ESS is ongoing in Lund, Sweden. This new high power spallation source with its long-pulse structure opens up new possibilities for fundamental physics experiments. This paper focusses on two proposals for fundamental physics at the ESS: The ANNI instrument and the neutron-anti-neutron oscillation experiment. (paper)

[en] There is considerable danger in the use of a method to sample the microcanonical momentum distribution that was recently suggested by Lopez and Randrup. (orig.)

[en] Preface The 8^th International Particle Accelerator Conference, IPAC’17, took place at the Bella Center Copenhagen, Denmark, from Sunday to Friday, 14 to 19 May, 2017. It was attended by more than 1350 full time delegates from approximately 34 different countries. All participants considered (incl. JACOW team, grant students and exhibitors), IPAC’17 was visited by 1550 people. Hosted by the European Spallation Source (ESS), it was supported by MAXIV and Aarhus University. It was organised under the auspices of the European Physical Society Accelerator Group (EPS-AG) and the International Union of Pure and Applied Physics (IUPAP). (paper)

[en] After a short summary of the design and the specifications of the ESS an overview of the current status and schedule of the ESS construction project will be given with a strong focus on the instruments and the surrounding scientific infrastructure. The overall goal of ESS is to begin user operation with 8 instruments in 2023. The plan is to reach the full scope of 22 public instruments by 2028. ESS will cover a very broad spectrum of science and is designed to push the limits of neutron methods to new horizons. Selected examples of new scientific opportunities will be discussed. (author)

[en] The 'minimal information' approach to nuclear fragmentation is related to other statistical descriptions. The minimal information approach is extended to allow internal excitation of the fragments and the resulting Lagrange constraint equations are shown to be identical to those of statistical models. (orig.)

[en] The α+d and t+τ cluster structure of ⁶Li is described in a microscopic α+d cluster model through quantities that enter into the description of cluster fragmentation processes. The states of the separate clusters α, d, t and τ are described as superpositions of Os Slater determinants belonging to different potential size parameters. To describe both the ⁶Li and fragment state realistically, nucleon-nucleon forces optimized for the used model state spaces were constructed. The fragmentation properties predicted by them slightly differ from those calculated with some forces of common use provided the latter are modified so as to reproduce the α, d and ⁶Li energies. (author) 61 refs.; 9 figs

[en] Short communication

[en] Mechanism of spallation is revealed experimentally. Spallation is a complicated nuclear reaction initiated by fast hadron in which three stages may be distinguished: a) the first stage in which the target nucleus is locally damaged, it lasts ∼10^-24+10^-22 s; b) the slow stage which lasts ∼10^-22+10^-17 s after the collision started, the damaged and excited nucleus uses to emit the black track leaving particles; c) the final stage in which residual target nucleus uses to split into two or more fragments. Quantitative characteristics of each of the stages are presented. 35 refs

[en] The possibility of applying the double-isotope-ratio method for calculating temperature to spallation products formed by high-energy protons is discussed. It is concluded that, at a specific incident-particle energy, spallation is characterized by a single temperature of the formation of products for targets in the mass range 56 ≤ A ≤ 208. No energy dependence of the temperature that was calculated by the double-isotope-ratio method was observed in the energy range 0.3 ≤ E ≤ 300 GeV.

[en] Recent heavy ion experiments have shown a multifragment breakup mode where most of the mass of the total system is divided among three to five fragments of roughly equal mass. The most striking feature of the mode is its large cross section, up to 22% of the total reaction cross section. The lightest member of the reacting pair ranged from Al to Kr. The beam energies ranged from 11 to 44 MeV/u. The available data can be explained as the breakup of nuclei with a toroidal shape. The model suggests that toroidal nuclei will be formed in any nuclear reaction if the reactants are heavy enough and the bombarding energy is the right range. (orig.)