We present optical spectroscopy of the nearest quasar pair listed in the 13th edition of the Véron-Cetty & Véron catalogue, i.e. the two quasars SDSS J15244+3032 and RXS J15244+3032 (redshift z≈0.27, angular separation Δ θ≈7″, and line-of-sight velocity difference ΔV≈1900 km/s). This system would be an optimal candidate to investigate the mutual

We present near-infrared (NIR) spectroscopic observations of 28 X-ray and mid-infrared sources at a median redshift of z˜0.8 in the Extended Groth Strip (EGS). To date this is the largest compilation of NIR spectra of active galactic nuclei (AGN) at this redshift. The data were obtained using the multi-object spectroscopic mode of the Long-slit

Population synthesis models are a tool extensively used to make inferences about the evolutionary status of stellar populations. In this work I examine the implicit priors assumed to obtain inferences by comparing observational data with populations synthesis models. As a result from this kind of study, I show how a higher spatial resolution can be

The standard physical mechanisms of the continuum emission in the microwave range are the synchrotron, free-free, and/or thermal dust emissions. Nevertheless, and based on observations over the last two decades, we can find a new process of emission, called Anomalous Microwave Emission (AME), which consists of an excess of dust-correlated microwave

The determination of oxygen abundance in nebulae requires measuring a significant number of emission lines distributed along a wide spectral range. The required measurements are hard to obtain at high redshift, where sources are very faint, and where the accessible spectral range is limited. These difficulties are often overcome using empirical

We classified the ˜10^6 galaxy spectra in SDSS/DR7 (Abazajian et al. 2009) into only 17 major classes (ASK classification; Sánchez Almeida et al. 2010). The algorithm provides the goodness of the classification for each individual spectrum and, therefore, a straightforward way to identify those targets which do not fit in the ASK classes. A