Time-series V and R photometry for the variable stars in NGC4147. (2 data files).

We present an eccentric, short-period brown dwarf candidate orbiting the active, slightly evolved subgiant star TYC 2087-00255-1, which has effective temperature T eff = 5903 ± 42 K, surface gravity log (g) = 4.07 ± 0.16 (cgs), and metallicity [Fe/H] = -0.23 ± 0.07. This candidate was discovered using data from the first two years of the Multi

CoRoT photometric measurements of asteroseismic targets need complementary ground-based spectroscopic observations. We are using the planet-hunter HARPS spectrograph attached to the 3.6m-ESO telescope in the framework of two consecutive Large Programmes. We discuss its use to study line-profile variations and we report on a specific result obtained

We present our on-going project to unveil the post-nova population by re-discovering old novae that have been lost after the initial outburst and in which the binary itself is unobserved. We take UBVR photometry for candidate selection, long-slit spectroscopy to confirm these candidates, and time-resolved spectroscopy to measure the orbital period

The Kepler spacecraft is providing photometric time series with micro-magnitude precision for thousands of variable stars, what opens up opportunities to study the pulsational variability in much more detail than was previously possible from the ground. We present a first general characterization of the variability of A-F type stars as observed in

With the first metal enrichment by Population III (Pop III) supernovae (SNe), the formation of the first metal-enriched, Pop II stars becomes possible. In turn, Pop III star formation and early metal enrichment are slowed by the high-energy radiation emitted by Pop II stars. Thus, through the SNe and radiation they produce, Pops II and III co