Since its discovery in 1992, the superluminal X-ray transient GRS 1915+105 has been extensively observed in an attempt to understand its behavior. We present here first results from a multiwavelength campaign undertaken from 1996 July to September. This study includes X-ray data from the RXTE All Sky Monitor and BATSE, two-frequency data from the

La tesis presenta los resultados del experimento Bartol-IAC sobre medidas de la anisotropía en el Fondo Cósmico de Microondas. Estas observaciones se realizaron en los meses de Junio y Julio de 1994 en el Observatorio del Teide. Se observó la región del cielo a delta=+40 grados en cuatro bandas a lamda=3,3; 2,1; 1,3 y 1,1 mm. En la tesis e han

El conocimiento de la distribución y evolución de los campos de velocidades a gran escala en la zona de convección solar es una de las claves para la comprensión tanto de los mecanismos de transporte energético, que en esta zona son principalmente convectivos, como de los fenómenos magnéticos allí presentes: actividad, dinamo solar, etc. En este

We have used the TAURUS Fabry-Perot mapping spectrometer on the WHT to produce a complete kinematic map of the disc of M100 in H-alpha. Here we show how the internal velocity dispersion of the principal emission components of the brightest regions varies with their H-alpha luminosity. The plot shows ample scatter, but an upper envelope in the

We present observational evidence of high-temperature spiral structure on the accretion disk of the dwarf nova IP Peg during outburst. The Doppler tomogram of ionized helium He II 4686 shows a two-arm spiral pattern on the disk image. The spiral shocks are generated by the tides raised by the secondary star on the disk and shows that a new

New improvements in the measurement of both the optical solar spectrum and laboratory wavelengths for lines of neutral iron are combined to extract central wavelength shifts for 1446 lines observed in the Sun. This provides the largest available database of accurate solar wavelengths useful as a reference for comparison with other solar-type stars