An effort is made to determine the differential rotation of the sun on the basis of the complete sample (1874-1976) of the Greenwich Photoheliographic Results. In order to improve the representation of differential rotation, a modified fit formula whose constant lies at 15 deg latitude (where sunspots nearly always occur) is introduced. Rotation is

EN LA PRESENTE TESIS SE ABORDA UNO DE LOS TEMAS DE MAS INTERES Y ACTUALIDAD DE LA FISICA SOLAR Y EN GENERAL DE LA ESTRUCTURA Y EVOLUCION ESTELAR. LA TECNICA DE OBSERVACION EL GRAN NUMERO DE ELLAS Y SU RIGUROSO ANALISIS HAN PERMITIDO LA DETECCION DE LOS MODOS GRAVITATORIOS DEL ESPECTRO DE OSCILACIONES SOLARES. SU IMPORTANCIA ES EXTRAORDINARIA POR

SE PONE EN PRACTICA DOS TECNICAS DE ALTA RESOLUCION ESPACIAL YA EN USO EN POCOS OBSERVATORIOS OPTIMIZANDO SU RENDIMIENTO. SE DISEÑA CONSTRUYE Y PRUEBA UN NUEVO INTERTEROMETRO QUE MEJORA OSTENSIBLEMENTE LA SENSIBILIDAD RESPECTO A LA TECNICA UTILIZADA HABITUALMENTE. SU IMPORTANCIA ESTRIBA EN LA CAPACIDAD DE RESOLVER LA ESTRUCTURA DE FUENTES

Not Available

The intensities obtained by measurement of the emission lines of neutral and ionized He at visible wavelengths in the April 24, 1981 white light flare are used as an observational basis for future radiative transfer models of such flares. Absolute peak and integrated intensities are given for the 14 lines of He I, as well as for the He II line at

Radial velocity measurements of the sun as a star using a resonant scattering spectrometer have been obtained at Izaña (Tenerife) during long observing seasons from 1976 to 1985. Its analysis shows that except for the global oscillations with periods shorter than one day there are stable signals with longer periods: at ≡13 days with mean amplitude