The study of gamma-ray blazars is usually hindered due to the lack of information on their redshifts and on their low-energy photon fields. This information is key to understand the effect on the gamma-ray absorption due to either extragalactic background light and/or intrinsic absorption and emission processes. All this information has also an

The study of gamma-ray blazars is usually hindered due to the lack of information on their redshifts and on their low-energy photon fields. This information is key to understand the effect on the gamma-ray absorption due to either extragalactic background light and/or intrinsic absorption and emission processes. All this information has also an

Galactic cosmic rays (CRs) inside the heliosphere are affected by solar modulation. To investigate this phenomenon and its underlying physical mechanisms, we have performed a data-driven analysis of the temporal dependence of the CR proton flux over the solar cycle. The modulation effect was modeled by means of stochastic simulations of cosmic

NEREA (Near Earths and high-Res Exoplanet Atmospheres) is a stable, compact, high-resolution spectrometer concept for the Gran Telescopio Canarias (GTC). The spectrograph is designed to be a common user instrument; however, its specifications are governed by two main science goals. (1) The discovery and characterization of planets around late-M

In 2018, Solar Cycle 24 entered into a solar minimum phase. During this period, 11 million zenithal night sky brightness (NSB) data were collected at different dark sites around the planet, including astronomical observatories and natural protected areas, with identical broadband Telescope Encoder and Sky Sensor photometers (based on the Unihedron

Using new, homogeneous, long-slit spectroscopy in the wavelength range from ~0.35 to $\sim 1 \, \mu$m, we study radial gradients of optical and near-infrared (NIR) initial mass function (IMF)-sensitive features along the major axis of the bulge of M31, out to a galactocentric distance of ~200 arcsec (~800 pc). Based on state-of-the-art stellar