Tag: Corona

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

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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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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

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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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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

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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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Nanoflares and nanojets and the coronal heating problem. The paper: “Reconnection Nanojets in the Solar Corona” of P. Antolin (Northumbria University) appeared on Nature Astronomy

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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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Pulsations in the solar corona. The study: “Large-amplitude quasi-periodic pulsations as evidence of impulsive heating in hot transient loop systems detected in the EUV with SDO/AIA” of F. Reale (UNIPA/INAF-OAPA) recently appeared on ApJ

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Solar corona is made of plasma at million degrees. The mechanism responsible for the heating of the corona, which is the outer part of the solar atmosphere, is still one of the unsolved problems of solar physics. For comparison, the plasma in the photosphere is on average at about 5600 degrees. It is widely accepted that the responsible for heating

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Impulsive heating of plasma in coronal loops. The study: “Impulsive coronal heating from large-scale magnetic rearrangements: from IRIS to SDO/AIA” of F. Reale (UNIPA/OAPA) recently appeared on ApJ

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The Solar corona is visible in the energetic bands of the electromagnetic spectrum as composed by magnetic arcs filled by plasma at million degrees, which are particularly bright in the active regions. Despite it is clear that the magnetic field plays a fundamental role in heating and confining the plasma, the Solar corona is still a complex region where energetic

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Flares and X-ray fluoresence in protostars. The study: “Deep X-ray view of the Class I YSO Elias 29 with XMM-Newton and NuSTAR” of I. Pillitteri (INAF-OAPA) recently appeared on A&A

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“Protostars” are stars a few million years old, which are still accreting gas and contracting for their own gravity, and whose nucleus has not reached yet the temperature and pressure necessary for the onset of thermonuclear reactions. The youngest protostars are still surrounded by a protoplanetary disk of gas and dust (class II protostars) or even by an accreting envelope

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Luglio 2017, la ricerca in evidenza: il Sole, un laboratorio unico per la fisica del plasma

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di Mario Giuseppe Guarcello    ( segui mguarce)     Solido, liquido e gassoso….questi sono gli stati della materia a cui siamo abituati sulla Terra. Nell’Universo non è esattamente cosi’. Il 99% della materia conosciuta (ed osservabile) nell’Universo infatti si trova sotto forma di plasma, uno stato che sulla Terra si trova naturalmente nei fulmini o nelle aurore boreali.   Cosa

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