Context. Parallaxes for 331 classical Cepheids, 31 Type II Cepheids, and 364 RR Lyrae stars in common between Gaia and the Hipparcos and Tycho-2 catalogues are published in Gaia Data Release 1 (DR1) as part of the Tycho-Gaia Astrometric Solution (TGAS). Aims: In order to test these first parallax measurements of the primary standard candles of the

X-ray binaries are formed by a compact object (either a stellar-mass black hole or a neutron star) and a donor star, which transfers mass onto the former via an accretion disc. They are usually discovered thanks to their bright X-ray radiation, but observations at other wavelengths are mandatory to fully understand and characterise their extreme

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A flat Friedmann-Robertson-Walker universe dominated by a cosmological constant (Λ) and cold dark matter (CDM) has been the working model preferred by cosmologists since the discovery of cosmic acceleration1,2. However, tensions of various degrees of significance are known to be present among existing datasets within the ΛCDM framework3-11. In

The cross section for the production of single top quarks in the t channel is measured in proton-proton collisions at 13TeV with the CMS detector at the LHC. The analyzed data correspond to an integrated luminosity of 2.2fb-1. The event selection requires one muon and two jets where one of the jets is identified as originating from a bottom quark

Desde el trabajo publicado en 1975 por Jöel Le Gall en el que analizaba la orientación de un número de ciudades romanas, se han sucedido varios estudios enfocados a conocer qué patrones siguen esos planos urbanos y si atienden a alguna motivación, de tipo simbólico o no. Sin embargo, el análisis llevado a cabo por Le Gall (1975) cuenta con varias