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The main goal of the AEgIS experiment at CERN is to test the weak equivalence principle for antimatter. We will measure the Earth's gravitational acceleration g with antihydrogen atoms being launched in a horizontal vacuum tube and traversing a moire deflectometer. We intend to use a position sensitive device made of nuclear emulsions (combined with a time-of-flight detector such as silicon μ� strips) to

IMBOSS is an experiment based on X-ray microcalorimeters and aimed to perform a high spectral resolution all-sky survey. One of the primary scientific goals is the observation of the baryon “missing” matter at z

The low transport current in granular high-Tc superconductors is undoubtedly attributed to the presence of weak links between grains. Magnetization and critical current measurements at very low field indicates that this low transport current behaves as expected from a critical state model. In this paper we show that a simple linear model of the granular system, based on an array of Josephson junctions and holes, can explain the existence of the critical state regime and shows dynamical effects, which have consequences even at low frequency, allowing for instance to explain the flux flow resistance of these materials.

I present a selection of magnetic measurements in sintered, laminated and polycrystalline HTSC, performed at very low field with a sensitive SQUID magnetometer. All the samples show hysteretic behaviour even at a few μTesla. The magnetization cycles can be desribed by a critical state model, with minor modifications due to the different morfology of the various materials.

We analyse the diamagnetic behaviour of high Tc superconducting granular samples by mean of an equivalent network of Josephson junctions and inductances. The range of validity of the current approaches is determined by considering the complete expression for the Gibbs thermodynamic potential and by identifying two characteristic parameters β1 and β2 for these systems. A graphical representation of the validity limits of various current approaches and in particular of the superconducting glass model is given in a β1-β2 plane.

In the present work self field correction of the critical current measurements of superconducting cables and wires is discussed. It is shown that the so called ‘peak field correction’ is not correct due to the inhomogeneity of the magnetic field at the cable. To correctly handle the measured values of critical current, a general criterion, based on an effective field correction, is proposed. Some experimental results were analysed and the two criteria are compared.

Measurements on the superconducting critical temperature Tc and critical field, Hc, of Zn Cr and Zn Mn alloys, down to 0.037°K are presented. The variation of Tc with increasing concentration depends strongly on Tcp/θ, with θ a characteristic temperature, while effects of Hc are similar to previously studied alloys.

The resistivity of Zn Cr and Zn Mn at concentrations lower than 6 ppm, levels off below 0.1°K with a concentration independent behaviour.