Detection of planets in the habitable zone is one of the key drivers of the exoplanet science community. We present a detailed strategy for such detection around L and T dwarfs. We plan to implement the outcome of the analysis as a transit survey to search for planets around known L and T dwarfs. Understanding of the variability of these cool

A new transient X-ray source was discovered in the 2011 August 26 Chandra ACIS observation of M31 (OBSID 12973), at RA = 00:42:11.37 DEC = +41:04:25.51. This system is likely to be a low mass X-ray binary with a black hole primary. The emission spectrum contained ~250 net source counts, and was well described by a power law with photon index 1.4 ±

We present a chemical abundance analysis of the secondary star in the black hole binary V404 Cygni, using Keck I/High Resolution Spectrometer. We adopt a χ2-minimization procedure to derive the stellar parameters, taking into account any possible veiling from the accretion disk. With these parameters we determine the atmospheric abundances of O, Na

Using high-resolution (R~30000), high-quality (S/N>=60 per pixel), we obtained spectra for twelve stars in four open clusters with the fibre spectrograph FOCES, at the 2.2 Calar Alto Telescope in Spain.We employ a classical equivalent-width analysis to obtain accurate abundances of sixteen elements: Al, Ba, Ca, Co, Cr, Fe, La,Mg, Na, Nd, Ni, Sc, Si

Sixteen years of observations of black hole transients with the Rossi X-ray Timing Explorer, complemented by other X-ray observatories and ground-based optical/infrared/radio telescopes have given us a clear view of the complex phenomenology associated with their bright outbursts. This has led to the definition of a small number of spectral/timing

We present the largest data base so far of atmospheric optical turbulence profiles [197 035 individual C2N(h)] for an astronomical site, the Roque de los Muchachos Observatory (La Palma, Spain). This C2N(h) data base was obtained through generalized SCIDAR observations at the 1-m Jacobus Kapteyn Telescope from 2004 February to 2009 August