Search

The neutron yield of a compact accelerator driven neutron source depends strongly on the target performance. This performance is influenced by the target composition and geometry, the cooling system design and which primary particles are used. We show that the temperature difference inside the target depends directly on the target thickness determined by the ion stopping range and therefore on the type and energy of the primary particle. Deuterons with a larger stopping power show a smaller temperature difference inside the target than protons allowing thus for a better target cooling.

Final LIMTECH Colloquium and International Symposium on Liquid Metal Technologies : 19-20 September 2017, Dresden, Germany / Gunter Gerbeth and Robert Stieglitz, colloquium co-chairs and co-editors Final LIMTECH Colloquium and International Symposium on Liquid Metal Technologies, Dresden, Germany, 19 Sep 2017 - 20 Sep 2017; London [u.a.] : Institute of Physics, IOP Conference Series-Materials Science and Engineering, 228, 012007 pp. (2017). doi:10.1088/1757-899X/228/1/012007, Published by Institute of Physics, London [u.a.]

The conventional Wien filter is a device with orthogonal static magnetic and electric fields, often used for velocity separation of charged particles. Here we describe the electromagnetic design calculations for a novel waveguide RF Wien filter that will be employed to solely manipulate the spins of protons or deuterons at frequencies of about 0.1 to 2 MHz at the COoler SYnchrotron COSY at J\"ulich. The device will be used in a future experiment that aims at measuring the proton and deuteron electric dipole moments, which are expected to be very small. Their determination, however, would have a huge impact on our understanding of the universe., Comment: 10 pages, 10 figures, 4 tables

In the following short article preliminary results concerning the high-power suitability of a solid-state target cooled by water as in SINQ are reported as available by the summer of 2010. The assessment warrants further and more detailed studies into an approach that appears to combine in an ideal way design maturity, ample positive operational experience, reliability, upgradability and minimum hazards and risks with acceptable neutron production.

Quite diverse concepts for targets have been proposed for ESS. While there is no doubt that different approaches are possible in principle, here it is argued that a large new neutron production facility, prepared for operation at an unprecedented power level, should rely as much as possible on proven technology. The neutron spallation sources SINQ and UCN at PSI feature as their standard a solid state target consisting of Zircaloy tubes filled with lead (“cannelloni”). These targets are cooled with heavy water. SINQ is currently being operated for the second decade at a power level of about 1 MW. A first quick assessment of the suitability of this target type for ESS conditions gives encouraging results but a wide variety of technical questions has still to be addressed in more detail. Possible paths for optimization as well as proposals for promising configurations are sketched.

Es ist bekannt, das Schallemissionssignale, die bei der Belastung polymerer Verbundwerkstoffe im Kurzzeit-Zugversuch auftreten, Indikatoren fur das lastabhangige Einsetzen bestimmter Schadigungsmechanismen darstellen. Am Beispiel von Polycarbonat mit unterschiedlichen Fullstoffgehalten wird nachgewiesen, das sich die Hohe einer statisch einaxial wirkenden Last auf den Charakter der wahrend des Kriechens emittierten Signale auswirkt. Es wird weiterhin aufgezeigt, das sich durch SE-Messungen der Zeitpunkt einer signifikanten anderung im Schadigungsfortschritt wahrend des Zeitraumes des sekundaren Kriechens ausweisen last. Aus den Resultaten der beschriebenen Messungen wird geschlossen, das die SE-Mestechnik, zumindest fur den gepruften Lastbereich, als Methode zur rechtzeitigen Warnung vor dem ultimativen Prufkorperversagen nutzbar ist. Acoustic emission (AE) signals as emitted by reinforced plastics in a tensile test are indicators for the load specific appearence of different failure mechanisms. Polycarbonate containing various percentages of glass fibres is used to demonstrate the influence of different constant load levels on the shape of AE events recorded during creep tests. Further it is shown that by the use of AE-techniques a serious change in damage progress is detectable in the range of secondary creep. It is concluded that AE testing at least in the considered range of load could be a tool for inspecting creeping polymers in terms of an early indication of the ultimate failure.