In this work we investigate the evolution of the X-ray emission of a cluster of single young massive stars with different metallicities. We have considered the X-ray contribution originated by the diffuse gas heated by the mechanical energy released by stellar winds and SN explosions as well as the X-ray contribution from SN remnants. The resulting

A recent study has suggested a link between the surface level diurnal temperature range (DTR) and variations in the cosmic ray (CR) flux. As the DTR is an effective proxy for cloud cover, this result supports the notion that widespread cloud changes may be induced by the CR flux. If confirmed, this would have significant implications for our

After several years of quiescence, the blazar CTA 102 underwent an exceptional outburst in 2012 September-October. The flare was tracked from γ-ray to near-infrared (NIR) frequencies, including Fermi and Swift data as well as photometric and polarimetric data from several observatories. An intensive Glast-Agile support programme of the Whole Earth

We have used observations made by the Global Oscillations at Low Frequency (GOLF) and the Variability of Irradiance and Gravity Oscillations Sun Photometer (VIRGO/SPM) instruments on board the ESA/NASA Solar and Heliospheric Observatory satellite to study variations in the excitation and damping of low angular degree (low-l) solar p-modes on the

We analyze Chandra observations of diffuse soft X-ray emission associated with a complete sample of 3CR radio galaxies at z 0.3. We focus on the properties of the spectroscopic sub-classes of high excitation galaxies (HEGs) and broad line objects (BLOs). Among the 33 HEGs we detect extended (or possibly extended) emission in about 40% of the

Spitzer IR Array Camera (IRAC) mid-infrared photometry is presented for the globular cluster (GC) systems of the NGC 5128 (`Centaurus A') and NGC 4594 (`Sombrero') galaxies. Existing optical photometric and spectroscopic are combined with this new data in a comprehensive optical-to-mid-IR colour catalogue of 260 GCs. Empirical colour-metallicity