Stellarium: Finally at Version 1.0! And Beyond

In this note, we show that there exist solutions of the Muskat problem that shift stability regimes: they start unstable, then become stable and finally return to the unstable regime. We also exhibit numerical evidence of solutions with medium-sized L(∞) norm of the derivative of the initial condition that develop a turning singularity.

This paper proposes a descriptive method for an open problem in time series analysis: determining the number of regimes in a switching autoregressive model. We will translate this problem into a classification one and define a criterion for hierarchically clustering different model fittings. Finally, the method will be tested on simulated examples and real-life data.

A selection of topics on open heavy quark production at HERA are reviewed here. Measurements of charm fragmentation parameters will be presented together with developments in the study of D di-jet angular distributions. Charm production in deep inelastic scattering (DIS) is also discussed. Finally we deal with recent measurements of b cross sections using impact parameters in both DIS and photo...