We present high time resolution optical spectroscopy and imaging of the black hole transient Swift J1357.2-0933 during its 2017 outburst. The light curves show recurrent dips resembling those discovered during the 2011 outburst. The dip properties (e.g. duration and depth) as well as the evolution of their recurrence time are similar to those seen

All stellar-mass black holes have hitherto been identified by X-rays emitted from gas that is accreting onto the black hole from a companion star. These systems are all binaries with a black-hole mass that is less than 30 times that of the Sun 1-4. Theory predicts, however, that X-ray-emitting systems form a minority of the total population of star

We present a super-Earth orbiting close to the inner edge of the habitable zone of the cool dwarf star K2-286 (EPIC 249889081), detected with data from the K2 mission in its 15th campaign. The planet has radius of 2.1 ± 0.2 R ⊕, near the 1.5-2.0 R ⊕ gap in the radii distribution. The equilibrium temperature is 347^{+21}_{-11} K, cooler than most of

We report on simultaneous sub-second optical and X-ray timing observations of the low-mass X-ray binary black hole candidate MAXI J1820+070. The bright 2018 outburst rise allowed simultaneous photometry in five optical bands (ugriz s) with HiPERCAM/GTC (Optical) at frame rates over 100 Hz, together with NICER/ISS observations (X-rays). Intense

En esta tesis se han abordado varios de los pasos necesarios (análisis del ruido instrumental, construcción de mapas, estimación de espectros de potencias) para el procesado de los datos de un experimento de polarización del Fondo Cósmico de Microondas (FCM), enfocándolos a la explotación cientı́fica del experimento QUIJOTE. En particular se

Aims: We aim at detecting water vapor in the atmosphere of the hot Jupiter HD 209458 b and perform a multi-band study in the near infrared with CARMENES. Methods: The water vapor absorption lines from the atmosphere of the planet are Doppler-shifted due to the large change in its radial velocity during transit. This shift is of the order of tens of