The total baryon content in the Universe is a well-defined quantity, in addition to being one of the most important cosmological parameters. A variety of observations (CMB, Ly-alpha forest, Big Bang nucleosynthesis) indicate that all baryons amount to around 4% of the total matter-energy content of the Universe. However, in the local Universe the contribution of all the observed components represents around 2% of the total. Therefore, half of the baryons in the local Universe remain elusive. In this article we have presented measurements of the kinematic Sunyaev-Zel’dovich effect in Planck data towards BOSS galaxies, that are compatible with the detection of all baryons in and around these galaxies (including the missing baryons), which represents around half of the total baryons in the Universe out to z=0.12, the maximum redshift sampled by these galaxies.
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H II regions are ionized nebulae associated with the formation of massive stars. They exhibit a wealth of emission lines in their spectra that form the basis for estimation of chemical composition. The amount of heavy chemical elements is essential to the understanding of important phenomena such as nucleosynthesis, star formation and chemical evolution of galaxies. For over 80 years, however, a discrepancy exists of a factor of around two between heavy-element abundances (the so-called metallicity) derived from the two main kinds of emission lines that can be measured in nebular spectra
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Red dwarfs are the most common stars in the galaxy. In recent years they have become key targets in the search for exoplanets. These stars are usually accompanied by rocky planets and due to their low brightness, their habitable zone is close to the star, making it easier to find planets that are within it. GJ 1002 is a red dwarf just one-eighth the mass of the Sun, located only 15.8 light-years away. Using radial velocity measurements from the ESPRESSO and CARMENES spectrographs, we have discovered the presence of two Earth-like and potentially habitable planets. The planets, GJ 1002 b and
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In the 90s, the COBE satellite discovered that not all the microwave emission from our Galaxy behaved as expected. Part of this signal was later assigned to a fresh new emission component, spatially correlated with the Galactic dust emission, which showed greater importance in the microwave range of frequencies. It has been named since as “anomalous microwave emission”, or AME. The current main hypothesis to explain the AME origin is that it is emitted by small dust particles which undergo fast spinning movements. In Fernández-Torreiro et al. (2023), we study the observational properties of
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