Galaxy morphology: how the growth of their bulge
shapes the evolution of galaxies

Speaker : Louis Quilley

Abstract :

Almost a century after the publication of the Hubble sequence (Hubble
1926), that classifies galaxies according to their shapes and features,
galaxy morphology remains a topical issue. Indeed, the structure of
galaxies provide insight on how they acquire their mass, grow their stellar
populations, and eventually cease their star formation. After presenting how
galaxy images can be analysed to characterize their morphologies, I will
describe how the properties of bulges and disks vary along the Hubble
sequence, and how galaxies of diverse morphologies are distributed across
the colour-mass diagram, as well as across various key scaling relations.
This will highlight how morphological transformations, and especially the
growth of the bulge, can be connected to their star-forming history. Then, I
will discuss how the capabilities of ESA’s latest space telescope Euclid,
launched in July 2023, can be leveraged to retrace the history of the
Hubble sequence, and I will present the first strides made in that avenue of
research, through the build-up of an unprecedented morphological
catalogue, and the first analyses of galaxy morphology across cosmic times
and along the Cosmic Web.