Category: Ricerca

Formation and evolution of the complex planetary system of V1298 Tau, described in the study: “The GAPS programme at TNG. XLVIII. The unusual formation history of V1298 Tau” of D. Turrini (INAF – OATo)

Ricerca

The study of the exoplanets orbiting around young stars (e.g., younger than a few tens of million of years) offer the important opportunity for studying the early evoalutionary phases of those processes that shape the architecture of planetary systems. However, it is quite difficult to detect and study exoplanets around young stars, because of their low number, the complexity of their

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The magnetic activity vs. age in binary systems with a white dwarf and a main sequence star. The study: “Main-sequence companions to white dwarfs – II. The age-activity-rotation relation from a sample of Gaia common proper motion pairs” of A. Rebassa-Mansergas (Universitat Politècnica de Catalunya) recently appeared on MNRAS

Ricerca

Several stellar phenomena and evolutionary processes are connected to their magnetic fields. The mechanisms that allow stars to produce their magnetic fields depend on their internal structure and stellar properties. One dominant property is stellar rotation: the faster stars rotate, the more intense their magnetic field and magnetic activity. Since stellar rotation declines with age, it is not surprising that

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A rich and complex planetary system for the star TOI-4010. The paper: “TOI-4010: A System of Three Large Short-period Planets with a Massive Long-period Companion” of M. Kunimoto (MIT) appeared on AJ)

Ricerca

To date (November 2023), we have confirmed the presence of 5539 exoplanets in 4128 planetary systems. These numbers indicate that, in the majority of cases, we have identified one planet per planetary system. This limitation is primarily due to observational constraints, as it remains challenging to detect small exoplanets with long orbital periods (distant from their stars several astronomical units,

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Micro-flares and the problem of the coronal heating. The paper: “Coronal energy release by MHD avalanches. Effects on a structured, active region, multi-threaded coronal loop” of G. Cozzo (UNIPA) appeared on A&A

Ricerca

The corona is the outermost part of the Solar atmosphere, filled with plasma at temperatures reaching several million degrees. The mechanism responsible for heating the Solar plasma to these temperatures is a long-standing problem. It began in the 1930s when physicists Bengt Edlen and Walter Grotrian proposed that the mysterious spectroscopic lines observed in the corona were not due to

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Young stars in massive star-forming regions. The results of the “Chandra Cygnus OB2 Legacy Survey” recently published

Ricerca

Today in the Milky Way, star formation typically occurs in low-mass environments. Young star clusters (e.g., younger than 10 million years), in fact, typically have a mass of a few hundred solar masses. Nevertheless, our Galaxy hosts a few very massive star-forming regions that can produce tens to hundreds of thousands of stars, including some of the most massive stars

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On the fequency of sub-neptunians in planetary systems with giant planets. The study: “The GAPS programme at TNG. XLVI. Deep search for low-mass planets in late-dwarf systems hosting cold Jupiters” of M. Pinamonti (INAF – OATo) appeared on A&A

Ricerca

The two giant planets of the Solar System, Jupiter and Saturn, played an important role in shaping the properties and architecture of the inner solar system. This may be a quite general rule. The presence of giant planets, for instance, can be responsible for a less effective migration of solids and gas toward the inner part of planetary systems, inhibiting

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A study on the coronal activity in a complete sample of M stars nearby to the Sun. The paper: “Complete X-ray census of M dwarfs in the solar neighborhood. I. GJ 745 AB: Coronal-hole stars in the 10 pc sample” of M. Caramazza (Eberhard-Karls Universität Tübingen) appeared on A&A

Ricerca

The corona is the outermost part of the atmosphere of the vast majority of stars, where the plasma is heated to millions of degrees by stellar magnetic activity. Since both the intensity and the topology of the stellar magnetic fields depend on the internal structure of stars, the study of coronal activity allows astronomers to better understand both the high-energy

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Stellar ages and lithium abundances. The study: “The Gaia-ESO Survey: empirical estimates of stellar ages from lithium equivalent widths (EAGLES)” of R. D. Jeffries (Keele University) appeared on MNRAS

Ricerca

Estimating stellar ages can prove to be a challenging task. The methods typically employed for estimating stellar ages rely on our understanding of how fundamental stellar properties that can be observed change as stars age. This often results in measurements that lack precision, particularly for stars in the main sequence, which is a stable evolutionary phase during which stellar properties

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Morphology and environment of the radiogalaxies. The study: “Investigating the large-scale environment of wide-angle tailed radio galaxies in the local Universe” of V. Missaglia (UniTo, OATo) appeared on A&A

Ricerca

Radiogalaxies are galaxies characterized by intense emission of radio waves, primarily produced by relativistic particles in motion along magnetic field lines (known as synchrotron emission). This radio emission is the result of the activity of a supermassive black hole situated at the center of these galaxies, giving rise to a plasma jet that extends over thousands or even millions of

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A planet and a brown dwarf for TOI-179. The paper: “TOI-179: A young system with a transiting compact Neptune-mass planet and a low-mass companion in outer orbit” of S. Desidera (INAF – OAPd) appeared on A&A

Ricerca

Typically, planets did not form at the distance from their central stars where we observe them today. In fact, during their early evolution, planets migrate from their initial orbit until the system reaches its final configuration. Planetary migration can be induced by several processes: the interaction between the newborn planets and the protoplanetary disk where they formed, the gravitational interaction

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