Category: Ricerca

Supernova remnants as particle accelerators. The study: “The supernova remnant SN 1006 as a Galactic particle accelerator” of R. Giuffrida (UniPA/INAF-OAPA) recently appeared on Nature Communication

Ricerca

Our planet is constantly bombarded by energetic particles (mainly protons) called “cosmic rays“. The study of cosmic rays is a leading science topic given its importance in several fields, such as the study of the effects on instrumentation and astronauts in space, where the natural protection against these particles provided by the magnetic field of Earth is low or null.

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A new catalog of the Young Stellar Objects within 4500 light years based on Gaia/EDR3. The study: “Low mass young stars in the Milky Way unveiled by DBSCAN and Gaia EDR3. Mapping the star forming regions within 1.5 Kpc” of L. Prisinzano (INAF – OAPA) recently published by A&A

Ricerca

After their formation, during the first few million of years (how many? it depends on the mass: the larger the stellar mass the faster is their evolution) stars continue to contract under their the action of their own gravity, rising their temperature and density. During this phase, their nuclei have not started yet the thermonuclear reactions that will power the

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Confirmed the existence of a neutron star in the center of SN1987A. The paper: “Additional Evidence for a Pulsar Wind Nebula in the Heart of SN 1987A from Multiepoch X-Ray Data and MHD Modeling” of E. Greco (University of Amsterdam; INAF-OAPA) recently appeared on Apj

Ricerca

SN1987A, the supernova exploded in the Large Magellanic Cloud (at about 170000 light years of distance) on February 23rd 1987, was an iconic event for the study of supernovae and supernova remnants. In fact, it is the only case where it was possible to observe (with telescopes) the explosion and to follow with periodic observations the evolution of the supernova

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Flares and variability in DS Tucanae A e AU Mic. The study: “Short-term variability of DS Tucanae A observed with TESS” of S. Colombo (INAF – OAPA) recently appeared on A&A

Ricerca

Stars are variable sources over timescales which depend on the phenomena triggering this variability. These phenomena are typically produced by the interaction between the stellar magnetic field and its plasma. Typical examples, observed and studied in great details in the Sun, are: flares (sudden release of a large amount of energy by the magnetic field which heats the gas in

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The interaction between star and planet triggers more energetic flares. The study: “X-ray variability of HD 189733 across eight years of XMM-Newton observations” of I. Pillitteri (INAF – OAPA) recently appeared on A&A

Ricerca

The corona is the outermost part of the atmosphere in stars with intermediate and low mass. In this region, which is extended for several stellar radii, the plasma can reach temperatures of several million degrees, emitting mainly X-ray radiation. The coronal temperature varies over a range of several orders of magnitude as a function of several stellar parameters, such as

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A large catalog of stars associated with stellar clusters recently compiled in the framework of the Gaia-ESO Survey.

Ricerca

Star clusters are a product of the star formation process. During their gravitational collapse, in fact, molecular clouds fragment forming hundreds or even thousands of stars. During the first few tens of million of years of their evolution, the young stars formed in a cloud are bound by the intense mutual gravitational attraction, forming a stellar cluster. Star clusters are important

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Magnetic activity and convection must be accounted for studying young stars . The paper: “Gaia-ESO Survey: Role of magnetic activity and starspots on pre-main-sequence lithium evolution” of E. Franciosini (INAF – OA Arcetri) recently appeared on A&A

Ricerca

Star clusters contain a rich population of stars covering a wide range of stellar masses (sometimes from the brown dwarfs to massive stars) with a well defined age. For this reason, star clusters represent fundamental targets to test the theoretical models describing stellar physics and evolution. However, this requires precise measurement of stellar clusters age. The method which is commonly

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Supernova explosions can trigger star formation events. The study: “Negative and positive feedback from a supernova remnant with SHREC: a detailed study of the shocked gas in IC443” of G. Cosentino (Chalmers University of Technology) recently appeared on MNRAS

Ricerca

A supernova is the final act of the evolution of a massive star. These spectacular explosions are among the most energetic events we observe in the Universe, and they can seriously impact the surrounding environment. In particular, during the expansions of the supernova remnants, which are the expanding clouds produced by supernova explosions, the process of star formation in the

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