Filaments in Cas A probe the processes occurred inside the progenitor during the explosion. The paper: “Filamentary ejecta network in Cassiopeia A reveals fingerprints of the supernova explosion mechanism” of S. Orlando (INAF-OAPA) appeared on A&A

A new theoretical study shows that the filamentary structure observed in the supernova remnant Cassiopeia A (Cas A) is a direct consequence of the processes that occurred in the progenitor star immediately after core collapse.   Supernovae are among the most energetic explosive events in the Universe. Yet, despite their immense brightness, they convert only about 1% of their energy

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A green monster inside Cas A unveils the secrets of its violent phenomena. The study: “The Green Monster Hiding in Front of Cas A: JWST Reveals a Dense and Dusty Circumstellar Structure Pockmarked by Ejecta Interactions” of I. de Looze (Ghent University) recently appeared on ApJL

There are many lessons about the physics of supernova remnants and progenitor stars that the Cassiopeia A (Cas A) supernova remnant teaches us. For example, we have learned that both the supernova explosion and the mass-loss episodes that characterize the final evolutionary stages of the progenitor star can be highly asymmetric. We have come to understand that supernovae can play

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Non thermal emission and cosmic rays in the supernova remnants SN1006. The paper: “”Hadronic particle acceleration in the supernova remnant SN 1006 as traced by Fermi-LAT observations” of M. Lemoine-Goumard (University of Bordeaux) appeared on A&A

Supernova remnants serve as unique laboratories to understand the complex processes occurring during a supernova explosion and to investigate the internal structure of massive stars just before their explosive demise. Additionally, the study of these remnants is driven by their crucial role in accelerating cosmic rays, which are particles with extremely high energies. In 1949, Enrico Fermi laid the groundwork for

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Chronology of a Supernova. The article: “Constraining the CSM structure and progenitor mass-loss history of interacting supernovae through 3D hydrodynamic modeling: The case of SN 2014C” by S. Orlando (INAF-OAPA), published in The Astrophysical Journal

The properties and morphology of supernova remnants result from complex physical processes in the progenitor star, both in the stages preceding the explosion and during the event itself. This involves the rapid collapse of the core, occurring in seconds, up to the shock wave reaching the star’s surface. Additionally, the supernova’s evolution is shaped by interactions between the star’s expelled

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A study on the processes responsible for the acceleration of particles in shocks. The study: “Individual particle approach to the diffusive shock acceleration. Effect of the non-uniform flow velocity downstream of the shock” of O. Petruk (INAF-OAPA) appeared on A&A

Our planet is constantly bombarded by highly energetic particles known as ‘cosmic rays‘. The spectrum of cosmic rays up to energies of 1015 electronvolts (eV) is formed by the sources in our Galaxy, while particles with observed energies up to 1021 eV should have extra-galactic origin. The cosmic ray spectrum follows a power law, meaning that the flux of particles with a given

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Simulated the XRISM observations of the iconic supernova remnant SN1987 A. The study: “Probing Shocked Ejecta in SN 1987A: A novel diagnostic approach using XRISM−Resolve” of V. Sapienza (UNIPA/OAPA) accepted on ApJL

SN1987 A is one of the most significant objects for studying supernova explosions and their remnants. This is because it is the only core-collapse supernova that has occurred relatively close to us (approximately 170000 light-years away, in the Large Magellanic Cloud) in the modern epoch. Therefore, it is the sole object of this type for which we have telescope observations

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γ-ray emission from the supernova remnants in the Large Magellanic Cloud. The paper: “High-energy γ-ray detection of supernova remnants in the Large Magellanic Cloud” of R. Campana (INAF – OAS) recently appeared on MNRAS

Supernova remnants are expanding nebulae produced by the explosion of high-mass stars. They are of great interest for understanding various physical processes and the final evolutionary stages of massive stars. Observations of supernova remnants in gamma rays are particularly important as they shed light on high-energy processes, such as the acceleration of cosmic rays (charged particles at very high energies).

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Different regimes of particle acceleration in supernova remnants. The study: “A Spatially Resolved Study of Hard X-Ray Emission in Kepler’s Supernova Remnant: Indications of Different Regimes of Particle Acceleration” of V. Sapienza (UNIPA/OAPA) appeared on ApJ

Cosmic rays are high-energy charged particles which continuously hit our planet. These particles are accelerated up to such high velocities in different astronomical environments, among which supernova remnants seems to be particularly important. These objects are nebulae in rapid expansion generated by the explosions of very massive stars. In supernova remnants, particle acceleration seems to occurr along the expanding shock

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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

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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Supernova explosions produced by LBV stars. The study: “Modeling the remnants of core-collapse supernovae from luminous blue variable stars” of S. Ustamujic (INAF-OAPA) recently appeared on Astronomy & Astrophysics

LBV (Luminous Blue Variable) stars are massive and unstable stars characterized by large mass-lost due to intense stellar winds and aperiodic bursts. Due to their instability, LBV stars are also variable, with quasi-periodic oscillations of their luminosity of the order of 0.5-2 magnitudes. Typical examples of this class of stars are: the supergiant S Doradus in the Large Magellanic Clouds,

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