Ultraluminous X-ray sources with the SKA

The discovery almost three decades ago of non-nuclear, point-like X-ray sources with X-ray luminosities LX ≥ 3 × 1039 erg s−1 revolutionized the physics of black hole accretion. If of stellar origin, such Ultraluminous X-ray sources (ULXs) would have to accrete at super-Eddington rates in order to reach the observed high X-ray luminosities. Alternatively, ULXs could host sub-Eddington accreting intermediate-mass black holes, which are the long-time sought missing link between stellar and supermassive black holes and the possible seeds of the supermassive black holes that formed in the early Universe. The nature of ULXs can be better investigated in those cases for which a radio counterpart is detected. Radio observations of ULXs have revealed a wide variety of morphologies and source types, from compact and extended jets to radio nebulae and transient behaviours, providing the best observational evidence for the presence of an intermediate-mass black hole in some of them. The high sensitivity of the SKA will allow us to study the faintest ULX radio counterparts in the Local Universe as well as to detect new sources at much larger distances. It will thus perform a leap step in understanding ULXs, their accretion physics, and their possible role as seed black holes in supermassive black hole and galaxy growth.

Pulsar science with the SKA

The unprecedented sensitivity and large field of view of SKA will be of paramount importance for pulsar science, and for many related research fields. In particular, beside the obvious discovery of many more pulsars (even those with very low luminosity), and the extremely accurate timing analysis of the current pulsar population, SKA will allow to use pulsars to measure or put strong constraints on gravitational waves, Galactic magnetism, planet masses, general relativity and nuclear physics.

La construcción de sistemas abovedados en la iglesia de Santiago Apóstol de Albatera (Alicante)

A lo largo del siglo XVIII, en la provincia de Alicante se construyeron multitud de templos con elementos abovedados ejecutados mediante ladrillo y yeso, encontrándose similitudes en cuanto a construcción, materiales y geometría. En muchos de ellos, el paso del tiempo ha ocasionado lesiones, siendo necesario realizar distintas intervenciones que, además de solucionar temporalmente el problema, son una valiosa fuente de información arquitectónica al permitir estudiar, analizar y comprender sus características constructivas. Dentro de los citados templos, la iglesia de Santiago Apóstol en Albatera [Alicante] es un ejemplo representativo de dichos elementos abovedados; por tanto, el estudio pormenorizado de sus intervenciones a lo largo del tiempo, atendiendo a los archivos gráficos y documentales existentes, permitirá conocer en profundidad las características principales de estos elementos constructivos singulares.