Recent study on the star cluster Dolidze25 suggests that protoplanetary disks disperse more rapidly in low-metallicity environments

Protoplanetary disks are disk-like structures that are found in low-mass stars younger than 10 million of years, typically called “pre-main sequence stars”. These disks are also the sites where planets formation occurs. In the last years, scientists have devoted a large effort to study the evolution and dispersion of protoplanetary disks. This has been possible also thanks to facilities such

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The planet orbiting the star DS Tuc A will loose about 10% of its total mass because of the evaporation induced by the incident stellar X-ray and UV radiation.

The study of planets orbiting around young stars (younger than 100 million years) can help astronomers understanding the physical processes setting the early evolution of planetary systems. However, young stars are typically characterized by rapid rotation and intense magnetic activity, phenomena which produce photometric and spectroscopic signals that can mimic and confuse those due to the presence of planets. It

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Jet and anisotropies in supernova remnants studied in the Vela SNR with XMM and ROSAT

Supernova remnants are clouds in rapid expansion formed by supernova explosions. Typically, these remnants are very inhomogeneous. These inhomogeneity is the result of the interaction between the expanding remnant and the surrounding material, and, in particular when they are generated by core-collapse supernova explosions (which are the supernova triggered by the gravitational collapse of the cores of massive stars), also to anisotropies formed

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A tridimensional hydrodynamic model explains the nature of the mixed-morphology supernova remnant

Supernova remnants are clouds in rapid expansion produced by supernova explosions. They are often characterized by a complex morphology, resulting from the interaction between the expanding remnants and surrounding clouds. Supernova remnants also emit radiation on a wide band of the electromagnetic spectrum. This is due to the variety of phenomena occurring in these objects, and because of the different

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Planets and metallicity: the relation valid for FGK stars extended also for M stars

The mechanisms involved in the formation of planets are still not completely understood. The most widely accepted model that describe the formation of gaseous planets is the core-accretion model. In this paradigm, the formation of these planets starts with the formation of a large rocky core by the coagulation of planetesimals, followed by the accretion of a large gaseous envelope

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The morphology of supernova remnants determined by anisotropies in the supernova explosion

Supernova explosions, occurring and the end of the life of massive stars, are ruled by a complex physics, and they can not be described by a simple spherically symmetric geometry. The rarity of these events make even more difficult to understand the physical processes involved during the explosions. For instance, on average only one supernova explodes in our Galaxy every

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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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