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Galactic Archaeology: decoding the fossil record of Galaxy formation and evolution

Sede A. Riccò Via Santa Sofia 78, Catania

One of most important issue in Astrophysics is the achievement of a robust understanding of the sequence of processes that contributed to the building up of the Milky Way. This is obviously important not only "on a local scale" in order to recover the history of formation and evolution of the Galaxy, but also, more in general, for understanding the formation process of spiral galaxies. In the last decade, the advent of high precision photometric and spectroscopic surveys as well as the possibility to estimate, thanks to the ESA Gaia mission, accurate distance for a huge number of field stars, combined with the development of an accurate theoretical framework, is actually opening a new era for this kind of investigations.
We will present some recent results - obtained by using this updated observational and theoretical framework - about the formation and early evolution of the Milky Way.

D.D. 362/2024 Pubblica selezione per titoli ed eventuale colloquio per il conferimento di un assegno di ricerca di professionalizzazione, della durata di 12 mesi, eventualmente prorogabili, dal titolo “Supporto alle attività MAIV del sistema “Camere” della missione PLATO”, nell’ambito del progetto PLATO – Fase D

Pubblica selezione per titoli ed eventuale colloquio per il conferimento di un assegno di ricerca di professionalizzazione, della durata di 12 mesi, eventualmente prorogabili, dal titolo “Supporto alle attività MAIV […]

DD 392/2024 Bando di selezione per titoli ed eventuale colloquio per il conferimento di n. 2 assegni di ricerca di “professionalizzazione” della durata di 12 mesi, eventualmente prorogabili, dal titolo “Diagnostica e modellistica di eventi eruttivi nell’atmosfera solare ”

Bando di selezione per titoli ed eventuale colloquio per il conferimento di n. 2 assegni di ricerca di "professionalizzazione" della durata di 12 mesi, eventualmente prorogabili, dal titolo “Diagnostica e modellistica di eventi eruttivi nell'atmosfera solare ”, nell’ambito della Partecipazione […]

The Hot Neptune Desert

Sede A. Riccò Via Santa Sofia 78, Catania

The vast majority of close-in planets are either massive hot Jupiters capable of holding their atmosphere against the stellar photoevaporation or small rocky planets completely drained by the stellar radiation. We observe an unexpected dearth of highly irradiated Neptune- and Saturn-like planets orbiting their host star in less than 4-10 days, called "Hot Neptune Desert". In this talk, I will present our recent findings from uniformly vetting 250 hot Neptune TESS candidates using a two-step vetting technique, as well as discuss a cutting-edge approach to examine the problem under a new perspective. I will also discuss how the PLATO mission may enhance our understanding of the Hot Neptunes.
We will present some recent results - obtained by using this updated observational and theoretical framework - about the formation and early evolution of the Milky Way.

Notte Europea dei Ricercatori 2024

In occasione della Notte Europea dei Ricercatori 2024, l’INAF-Osservatorio Astrofisico di Catania ha organizzato varie attività per il pubblico che si svolgeranno tra il 27 e il 28 settembre.

Unraveling Space Weathering on Planetary and Astrophysical Surfaces

Sede A. Riccò Via Santa Sofia 78, Catania

It is well known that the interaction of energetic ions, electrons and photons with surfaces and interfaces leads to non-thermal desorption via a process typically referred to as desorption induced by electronic transitions (DIET).  When DIET involves either electrons or photons, these processes are generally referred to as electron-stimulated desorption and photon-stimulated desorption (PSD), respectively.  Recent attention has focused on understanding the role of non-thermal “space weathering” in the processing of interstellar grains and ices.
Specifically, there is deep interest in understanding the radiation processing of carbon grains in the solar nebula and unraveling the H2O formation mechanisms in solar nebula and planetary systems, including the Moon. Using graphite grains, the VUV photon-simulated oxidation of carbon grains via reactive scattering of water fragments produced by dissociative electron attachment at the buried interface was examined. The results suggested that VUV PSD at the buried water:carbon grain interface may help control the carbon inventory during planet formation. The inverse process, (i.e, the formation of water) may happen on metal-oxide samples such as mineral grains and lunar regolith samples, that contain or are terminated by hydroxyl groups. Solar wind space weathering experiments of several Apollo lunar samples demonstrated that thermally activated recombinative desorption (RD) can be H2O sources and that electron-stimulated reactive scattering to produce water may also be occurring, especially when the Moon is in the magnetopause.  RD can occur on a diurnal basis on the Moon and is prevalent during meteoroid impacts. The latter is simulated by laser irradiation studies followed by state and velocity resolved detection of the produced water.  Finally, evidence of space weathering and surface alteration has also been revealed using spatially resolved, high-resolution nanoscale Fourier transform infrared imaging/spectroscopy correlated with photoluminescence (PL) on Apollo samples with different origins and history.

D.D. 499/2024 Pubblica selezione per titoli e colloquio per il conferimento di un assegno di ricerca di professionalizzazione, della durata di 12 mesi, eventualmente prorogabili, dal titolo “Sviluppo di tecniche di Visual Analytics e Machine Learning per il Progetto SKAVA”, nell’ambito del progetto SKAVA: SKA Visual Analytics

Pubblica selezione per titoli e colloquio per il conferimento di un assegno di ricerca di professionalizzazione, della durata di 12 mesi, eventualmente prorogabili, dal titolo “Sviluppo di tecniche di Visual […]

Stellar-wind-fed magnetospheres of magnetic massive stars

Sede A. Riccò Via Santa Sofia 78, Catania

A subpopulation (~9%) of hot (OB) stars exhibit strong (B~100-10,000 G), large-scale (often predominantly dipolar) magnetic fields that channel their stellar wind outflows into circumstellar magnetospheres. For young, rapidly rotating B-stars that have not yet been spun down by wind-magnetic braking, wind material can be trapped between the Kepler co-rotation radius (RK) and the Alfven radius (RA), forming then a “Centrifugal Magnetosphere” (CM), with density set at the critical level for “Centrifugal Breakout” (CBO) against the confining magnetic tension. This talk discusses how such CBO controls both the onset and strength of observed H-alpha emission, while the energetics of the associated CBO-driven magnetic reconnection match well the observed scalings of a non-thermal, circularly polarized radio emission from such stars .

Spectroscopic observations and modeling of solar flares: new insights from IRIS

Sede A. Riccò Via Santa Sofia 78, Catania

Recent high-resolution observations from the IRIS satellites have enabled significant advancements in our understanding of the physical mechanisms at play during the impulsive phase of flares, including details of how the non-thermal energy is released and propagated from the corona to the low-atmosphere through accelerated particles. At the same time, the new discoveries have brought to light new unsolved questions and challenges for current models. This talk will provide some examples of the unique contributions to our understanding of flares from IRIS, also in coordination with other solar observatories, and how state-of-the-art heating models of flares can be constrained by the available imaging and spectral diagnostics. I will also discuss some of the outstanding problems in preparation for the next generation of solar missions.