The neutron star transient SAX J1750.8-2900 has been in outburst since March 15th, 2008 (ATel #1425). The X-ray flux started to decay around mid May and fell below the detection threshold of RXTE-ASM and Swift-BAT around August 2nd and 8th, respectively. We report here on a Swift-XRT observation of the source during its transition to the quiescent

Lucky imaging techniques implemented by the FastCam group (see http://www.iac.es/proyecto/fastcam/) at the Instituto de Astrofisica de Canarias have demonstrated its ability to obtain spectacular diffraction limited images in telescopes ranging from 1 to 4.2 m in visible wavelengths (mainly in the I band), at the expense of using only a small

We present the design for a high-speed readout imaging mode for the Canarias InfraRed Camera Experiment (CIRCE), a visitor-class near-IR imager, spectrograph, and polarimeter for the 10.4 meter Gran Telescopio Canarias (GTC). This mode, along with the polarimetric and spectroscopic capabilities of the instrument will provide a powerful and unique

Accurate calibration of data is essential for the current generation of cosmic microwave background (CMB) experiments. Using data from the Very Small Array (VSA), we describe procedures which will lead to an accuracy of 1 per cent or better for experiments such as the VSA and CBI. Particular attention is paid to the stability of the receiver

The Canarias InfraRed Camera Experiment (CIRCE) for the Gran Telescopio Canarias (GTC) is one of the few infrared instruments in the world using a four-beam polarimeter. The classical double-beam configuration consists of a half-wave plate (HWP) and a Wollaston Prism (WP) that allow measurement of two linear polarization components of the light in

Aims: Our main objective is to develop a denoising strategy to increase the signal to noise ratio of individual spectral lines of stellar spectropolarimetric observations. Methods: We use a multivariate statistics technique called Principal Component Analysis. The cross-product matrix of the observations is diagonalized to obtain the eigenvectors