Tight stability requirements for the imager/spectrograph OSIRIS (a Day One optical instrument for the GTC telescope) demand a careful treatment of thermal effects within the OSIRIS camera. Mostly due to the thermal response of refraction indices of its glasses (and not so much to curvature, spacing or thickness variations of the lenses), the camera

We present optical photometry of XTE J2123-058 taken in 1999 and 2000, during its quiescent state. The dominant feature of our R-band light curve is the ellipsoidal modulation of the secondary star; however, in order to fit this satisfactorily, we require additional components that comprise an X-ray-heated Roche lobe-filling secondary star and an

We present here the results of an imaging study of eight grand-design and two intermediate-arm galaxies, based on CCD observations in U, B, V, R and I. We give grey-scale images, both in individual and in colour indices. Also we present a decomposition into bulge and disc following an iterative method. This provides us with a reasonable estimate of

Photospheric abundances are presented for 27 elements from carbon to europium in 181 F and G dwarfs from a differential local thermodynamic equilibrium (LTE) analysis of high-resolution and high signal-to-noise ratio spectra. Stellar effective temperatures (Teff) were adopted from an infrared flux method calibration of Strömgren photometry. Stellar

We describe an unusual undergraduate course that has been running successfully for over ten years and is built around a two-week field trip to Tenerife. The purpose of the visit is twofold: firstly to spend a week working in collaboration with students from the Universidad de La Laguna and secondly to spend a week at the Observatario del Teide

EMIR is a intermediate resolution near infrared (1.0 - 2.5 microns) multiobject spectrograph with image capabilities, to be mounted on the Gran Telescopio Canarias (GTC). EMIR is being built by a consortium of Spanish, French and British institutions, led by the Instituto de Astrofísica de Canarias. EMIR is being funded by GRANTECAN and the Plan