Descrizione del progetto
Osservazione dei flussi di gas intorno alle galassie e del loro modo di plasmarne l’evoluzione
Le galassie sono sistemi di miliardi di stelle, gas e polvere, tutti tenuti insieme dalla gravità. A causa delle interazioni reciproche tra questi componenti, la struttura interna di una galassia cambia nel tempo. Un attore essenziale in queste trasformazioni è il mezzo circumgalattico (CGM), un enorme serbatoio dinamico di gas. La materia fluisce dal CGM nella galassia per formare nuove stelle, ma viene anche spinta fuori da esplosioni all’interno della galassia. Il progetto SPECMAP-CGM, finanziato dall’UE, userà due strumenti particolarmente sensibili presso importanti osservatori e sfrutterà nuovi metodi di rilevamento per mappare spettroscopicamente centinaia di galassie contemporaneamente, rilevare la debole emissione dal CGM e quindi definire i complessi processi che plasmano l’evoluzione delle galassie.
Obiettivo
This project aims at developing a radically new view on the structure and dynamics of gas flows in the surroundings of galaxies, a domain known as the circumgalactic medium (CGM). In the last years it became clear that the CGM is crucial for our understanding of galaxy evolution, which are largely shaped in the CGM by the interplay of inflows from the intergalactic medium and outflows driven by supergalactic winds. I plan to investigate the CGM of normal galaxies by means of integral field spectroscopy, or spectro-mapping, in various emission lines. I bring privileged access to two new major astronomical facilities, MUSE on the ESO Very Large Telescope in Chile, and HETDEX on the 10m Hobby-Eberly Telescope in Texas. These instruments are both unique in their capability of performing integral field spectroscopy over unprecedented fields of view, delivering high-quality spectro-mapping information for hundreds of galaxies and their circumgalactic environments simultaneously. I have a leading role in both, and I am the only astronomer in the world with direct access to MUSE Guaranteed Time Observations and to the entire HETDEX survey. The major challenge for this experiment is the extreme faintness of the CGM emission, which so far made spectro-mapping unfeasible except for a few extreme objects. My recent breakthrough discoveries with MUSE of ubiquitous Lyman-alpha haloes around high-redshift galaxies demonstrate that finally we have achieved the sensitivity required to detect the CGM directly in emission through imaging spectroscopy. I now want to go a big step beyond and apply this approach to large representative samples of typical galaxies at all redshifts. My goal is not only to detect and establish line emission from the CGM as a universal phenomenon, but to disantangle its complex substructures and, through comparisons with physical models and the latest numerical galaxy formation simulations, build a comprehensive picture of these processes.
Campo scientifico
Programma(i)
Argomento(i)
Meccanismo di finanziamento
ERC-ADG - Advanced GrantIstituzione ospitante
14482 Potsdam
Germania