Identity and identification of Trogulus banaticus (Opiliones: Trogulidae) : a neglected species in the Northern Balkans

Trogulus banaticus Avram, 1971 is characterised and recorded as new for Slovenia. This species was previously mistaken for T. coriziformis C. L. Koch, 1839 and T. graecus Dahl, 1903 which were later rejected from the Slovenian fauna. T. banaticus is compared with the similar, and partly sympatric, T. tingiformis C. L. Koch, 1847 with which it has often been confused. A table of distinguishing characters for both species is provided, and the ecology of T. banaticus and its general distribution are discussed

Hysteresis between distinct modes of turbulent dynamos

Nonlinear mean-field models of the solar dynamo show long-term variability, which may be relevant to different states of activity inferred from long-term radiocarbon data. This paper is aimed to probe the dynamo hysteresis predicted by the recent mean-field models of Kitchatinov \& Olemskoy (2010) with direct numerical simulations. We perform three-dimensional simulations of large-scale dynamos in a shearing box with helically forced turbulence. As initial condition, we either take a weak random magnetic field or we start from a snapshot of an earlier simulation. Two quasi-stable states are found to coexist in a certain range of parameters close to the onset of the large-scale dynamo. The simulations converge to one of these states depending on the initial conditions. When either the fractional helicity or the magnetic Prandtl number is increased between successive runs above the critical value for onset of the dynamo, the field strength jumps to a finite value. However, when the fractional helicity or the magnetic Prandtl number is then decreased again, the field strength stays at a similar value (strong field branch) even below the original onset. We also observe intermittent decaying phases away from the strong field branch close to the point where large-scale dynamo action is just possible. The dynamo hysteresis seen previously in mean-field models is thus reproduced by 3D simulations. Its possible relation to distinct modes of solar activity such as grand minima is discussed.Comment: Published in Ap

Dynamics of thin-film spin-flip transistors with perpendicular source-drain magnetizations

A "spin-flip transistor" is a lateral spin valve consisting of ferromagnetic source drain contacts to a thin-film normal-metal island with an electrically floating ferromagnetic base contact on top. We analyze the \emph{dc}-current-driven magnetization dynamics of spin-flip transistors in which the source-drain contacts are magnetized perpendicularly to the device plane by magnetoelectronic circuit theory and the macrospin Landau-Lifshitz-Gilbert equation. Spin flip scattering and spin pumping effects are taken into account. We find a steady-state rotation of the base magnetization at GHz frequencies that is tuneable by the source-drain bias. We discuss the advantages of the lateral structure for high-frequency generation and actuation of nanomechanical systems over recently proposed nanopillar structures.Comment: Accepted by Phys.Rev.B as regular articl