The magnetic activity of the M star AD Leo

Stars which are not fully radiative (e.g., less massive than 8 solar masses) produce a magnetic field in their interior whose intensity and topology depends on the type of star and internal structure. The magnetic field is then drag toward the surface and here it interacts with the plasma in the photosphere, chromosphere, and corona triggering phenomena classified as “magnetic

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A step forward the comprehension of solal corona heating: Observed for the first time coronal nanojets

Solar corona is the outer atmosphere of our star. Extended for several solar radii, it is made of million degrees plasma, thus being hotter than the gas in the photosphere (about 5600 degrees). Several scientist have tried understanding the mechanism responsible for the heating of coronal plasma, but it is has been an open issue for decades. The most promising

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A new diagnostic tool to select metal-rich ejects in SNR

Supernova remnants are nebulae created by supernova explosions. These expanding clouds are formed by the interstellar medium shocked and heated up by the expanding shock produced by the explosion, and the knots of material launched by the exploding star, called ejecta. These ejecta are located behind the expanding shock, traveling with lower velocity, and they are heated up by the reverse shock:

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A new method based on the Principal Components Analysis allows to remove systematics from Kepler/K2 light curves

Several fields in modern astronomy rely on high-precision photometric data. This is true, in particular, for the search of exoplanets with the method of transits. This method consists in searching very small periodic dimming of stellar emission due to the transit of planets along the line of sight during their orbits. For instance, the transit due to a Hot Jupiter (a gaseous

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The bimodal distribution of exoplanets radii dictated by ambient UV radiation

To date (2020 March 23rd) there are 4141 confirmed exoplanets in 3072 planetary systems, plus 5075 candidate exoplanets that still await to be confirmed (data from https://exoplanets.nasa.gov/). The number of known exoplanets is large enough to allow astronomers to study their global properties such as mass distribution, orbital parameters, planets dimension and composition, and to put them in relation with the

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