Obiettivo The classic problem in the formation of high-mass stars is that, for all stars above ~20 Msun, the outward force exerted by the stars radiation on the dusty circumstellar gas should be capable of reversing or halting accretion flows. Core fragmentation, pressure from the expanding ionised gas, magnetic fields and mass loss through stellar winds, all work against the effects of gravity, thereby restricting the final stellar mass. Advances in theoretical models, aided by numerical simulations (e.g. adaptive mesh refinement), have proposed elegant solutions; for example, the interaction between radiation and the dense circumstellar gas is subject to radiation-Rayleigh-Taylor instability, creating low opacity chimneys to vent out the radiation pressure. Likewise, heated cores and disks are stable against Jeans fragmentation. The exact manifestation of these issues and their solutions vary significantly between theories, and the physical structures found around embedded, still accreting massive stars provides a strong discriminator between models. Therefore, this research project aims to better understand the physical conditions of the gas and dust structures within the 500-5000 AU regions of infant high-mass stars by using adaptive-optics-assisted polarimetric observations in the infrared (essential to probe through the high extinction of high-mass cores). Also, we will characterise and quantify, for the first time, the stellar activity, mass, and radius of high-mass (young/proto) stars which are thought to be bloated and pulsating objects. To this end, variability and astero-seismological studies will be conducted. The applicant seeks mobility to a host institute that is a world leader in polarimetry, where he will acquire new expertise in astrophysical polarimetry through training by research. This program will distinguish between and test mechanisms of massive star formation, taking important steps to understand a long standing problem of astrophysics. Campo scientifico natural sciencescomputer and information sciencesdata sciencenatural sciencescomputer and information sciencesdatabasesnatural sciencesphysical sciencesastronomyastrophysicsblack holesnatural sciencesphysical sciencesnuclear physicsnuclear fusionnatural sciencesphysical sciencesastronomyobservational astronomy Programma(i) H2020-EU.1.3. - EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions Main Programme H2020-EU.1.3.2. - Nurturing excellence by means of cross-border and cross-sector mobility Argomento(i) MSCA-IF-2014-EF - Marie Skłodowska-Curie Individual Fellowships (IF-EF) Invito a presentare proposte H2020-MSCA-IF-2014 Vedi altri progetti per questo bando Meccanismo di finanziamento MSCA-IF-EF-ST - Standard EF Coordinatore THE UNIVERSITY OF HERTFORDSHIRE HIGHER EDUCATION CORPORATION Contribution nette de l'UE € 183 454,80 Indirizzo COLLEGE LANE AL10 9AB Hatfield Regno Unito Mostra sulla mappa Regione East of England Bedfordshire and Hertfordshire Hertfordshire Tipo di attività Higher or Secondary Education Establishments Collegamenti Contatta l’organizzazione Opens in new window Sito web Opens in new window Partecipazione a programmi di R&I dell'UE Opens in new window Rete di collaborazione HORIZON Opens in new window Costo totale € 183 454,80