We discuss a 175 deg2 spectroscopic survey for blue horizontal branch (BHB) stars in the Galactic halo. We use the Two Micron All Sky Survey (2MASS) and the Sloan Digital Sky Survey (SDSS) to select BHB candidates, and we find that the 2MASS and SDSS color selection is 38% and 50% efficient, respectively, for BHB stars. Our samples include one

Most of what we know about the stellar population of nearby, resolved galaxies comes from the interpretation of their color-magnitude diagrams, by comparison with stellar evolutionary models. We review how well current stellar evolution models reproduce the properties of simple stellar populations. Emphasis is given to the regions of the color

We review some recent developments which make use of the concept of `superstatistics', an effective description for nonequilibrium systems with a varying intensive parameter such as the inverse temperature. We describe how the asymptotic decay of stationary probability densities can be determined using a variational principle, and present some new

We have conducted a systematic search for stellar disk truncations in disklike galaxies at intermediate redshift (z

We present the results of spectroscopic follow-up observations for a sample of 71 red objects with high proper motions in the range 0.08-1.14 arcsec yr-1 as detected using APM and SSS measurements of multi-epoch photographic Schmidt plates. Red objects were selected by combining the photographic B_JRI magnitudes with 2MASS near-infrared JHKs

One of the proposed damping mechanisms of coronal transverse loop oscillations in the kink mode is resonant absorption as a result of the spatial variation of the Alfvén velocity in the equilibrium configuration. Analytical expressions for the period and the damping time exist for 1-D cylindrical equilibrium models with thin non-uniform