Descrizione del progetto
Nuove intuizioni sui venti delle stelle giganti e supergiganti fredde
La vita come noi la conosciamo non esisterebbe senza i venti stellari, flussi di gas e polvere in rapido movimento espulsi dalle stelle. Gli scienziati tuttavia non sanno ancora abbastanza sui venti stellari da essere in grado di formare un quadro realistico di come influenzino l’evoluzione stellare e contribuiscano ad arricchire il mezzo interstellare. Utilizzando un nuovo approccio di modellizzazione, il progetto EXWINGS, finanziato dall’UE, intende fornire una nuova visione dei venti di stelle giganti e supergiganti fredde. A tal fine, utilizzerà un prototipo recentemente sviluppato per ottenere simulazioni idrodinamiche con radiazione del tipo «star-and-wind-in-a-box» (stella e vento in una scatola). Ciò renderà possibile per la prima volta seguire il flusso di materia in una geometria 3D completa. Il progetto promuoverà le conoscenze scientifiche sull’evoluzione chimica stellare e galattica.
Obiettivo
Without stellar winds, life as we know it would not exist. Critical elements like carbon are produced inside luminous cool giant stars, transported to the surface by turbulent gas flows, and ejected into interstellar space by massive outflows of gas and dust. Direct evidence for this scenario comes in the form of dust grains produced in the stellar winds, and detected in meteorites by their isotopic composition. Nevertheless, the current understanding of stellar winds is far from sufficient to draw a realistic, quantitative picture of their effects on stellar evolution and their contribution to the enrichment of the interstellar medium with newly-produced elements and dust.
Project EXWINGS aims at a breakthrough in understanding the winds of cool giant and supergiant stars with a novel modeling approach. We will produce global radiation-hydrodynamical ‘star-and-wind-in-a-box’ simulations, based on our recently-developed prototype. For the first time, it will be possible to follow the flow of matter, in full 3D geometry, all the way from the convective, pulsating interior of a cool giant, through its atmosphere and dust-formation zone, into the dust-driven wind region. Extending our unique approach to the warmer, more luminous red supergiants, we will explore alternative driving scenarios for their still enigmatic winds, involving magneto-hydrodynamic waves and radiation pressure on molecules and dust.
The current progress in high-angular-resolution instruments, giving resolved views of the stellar atmospheres where the winds originate, presents an excellent opportunity for testing the new models. An ultimate goal is a predictive theory of mass loss and dust production in evolved stars, based on first physical principles. The results of EXWINGS will have a major impact on understanding stellar and galactic chemical evolution, on tracing the origin of building blocks for terrestrial planets, and on constraining physical properties of supernova progenitors.
Campo scientifico
- natural sciencesphysical sciencesastronomystellar astronomyneutron stars
- natural sciencesphysical sciencesastronomyplanetary sciencesmeteorites
- natural sciencesphysical sciencesastronomyplanetary sciencesplanets
- natural sciencesphysical sciencesastronomyplanetary sciencescelestial mechanics
- natural sciencesphysical sciencesastronomystellar astronomysupernova
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-ADG - Advanced GrantIstituzione ospitante
751 05 Uppsala
Svezia