We conduct a search for the He − η bound state with the WASAat-COSY facility via the measurement of the excitation function for the reaction dd → He p π−. In first experiment performed in June 2008, we used COSY deuteron beam with a slowly ramped beam momentum corresponding to a variation of the excess energy for the Heη system from -51.4 MeV to 22 MeV. Here we report on the status of the measu...

In 1996 Lee, Osheroff and Richardson received the Nobel Prize for their 1971 discovery of superfluid helium 3 – a discovery which opened the door to the most fascinating system known in condensed matter physics. The superfluid phases of helium 3, originating from pair condensation of helium 3 atoms, turned out to be the ideal test-system for many fundamental concepts of modern physics, such as ...

Staphylococcus aureus showed decreased susceptibility to penicillin, vancomycin, sodium cephalothin, and tetracycline, but increased susceptibility to sodium colistimethate, at a pressure of 68 atm in helium or helium-oxygen gas. Susceptibility of Streptococcus pyogenes was unchanged by pressurization.

During the last decades, superfluid helium clusters have been widely studied both experimentally and theoretically. As a result of the latter studies, a new spectroscopic domain has emerged (HENDI) where helium nanodroplets are used as ultimate matrices for accurate spectroscopic measurements, taking advantage of their very low temperature and their weak interaction with the impurity. However, ...

We describe a method for dark matter detection based on the evaporation of helium atoms from a cold surface and their subsequent detection using field ionization. When a dark matter particle scatters off a nucleus of the target material, elementary excitations (phonons or rotons) are produced. Excitations which have an energy greater than the binding energy of helium to the surface can result i...

A fatigue test method by a miniaturized hourglass-shaped fatigue specimen has been developed for International Fusion Materials Irradiation Facility (IFMIF) and sufficient potential as the alternative to a conventional large specimen was presented. Furthermore, focused ion beam micro-sampling method was successfully applied to microstructural analysis on fracture process. Where, the effects of ...

The dynamics of vibrational wave packets excited in K2 dimers attached to superfluid helium nanodroplets is investigated by means of femtosecond pump-probe spectroscopy. The employed resonant three-photon-ionization scheme is studied in a wide wavelength range and different pathways leading to K 2 -formation are identified. While the wave packet dynamics of the electronic ground state is not in...

Helium is thermodynamically insoluble in metals and tends to form cavities if the conditions are appropriate for its migration. The processes of helium migration and interaction with point defects are strongly influenced by the level and the mode of displacement damage production. In this paper, we present an application of the rate theory for helium cavity formation in Inertial Confinement Fus...

The properties of hydrogen-helium mixtures at Mbar pressures and intermediate temperatures (4000 to 10000 K) are calculated with first-principles molecular dynamics simulations. We determine the equation of state as a function of density, temperature, and composition and, using thermodynamic integration, we estimate the Gibbs free energy of mixing, thereby determining the temperature, at a give...