Research

My research is in the area of observational extragalactic astronomy, and my main interest is the study of the physical properties of galaxies and their dependence on redshift and environment using large, multi- wavelength datasets. The multi-wavelength approach is at the foundation of my research activity, as it is the only way to trace all the baryonic constituents of galaxies and to reveal how the Universe formed and evolves.

Thus, I am currently involved in several large projects aimed at improving our understanding of how galaxies form and evolve. The topics on which I currently spend great part of my research work include:

Recently, I am mainly working on the following topics

  • The effects of the environment on the star formation and gas cycle of of galaxies
  • The role of stellar and gas kinematics in shaping the Hubble sequence
  • The chemical enrichment history of the interstellar medium in galaxies
  • The interplay between infall and outflow in regulating the life of galaxies

For more information in my recent research results, please have a look at the News page.

Below, I list my major scientific achievements so far:

A unified dynamical scaling relation for all galaxies. By taking advantage of the unprecedented quality of spatially-resolved velocity maps obtained as part of the SAMI survey, I have shown that galaxies of all morphologies follow a tighty relation linking their dynamical and stellar mass. This provides a unique tool for understanding the relation between kinematics and baryonic content of galaxies (see paper).

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The role of the cluster environment on the star formation cycle of galaxies. My works on the Herschel Reference Survey have provided us with complete and coherent view of the evolution of nearby cluster galaxies. Firstly, we demonstrated that feedback from supermassive black-holes is not responsible for quenching the star formation in green-valley galaxies (see paper) but that gas stripping by the cluster environment is driving the migration of galaxies from the blue to the red sequence (see paper). Secondly, by combining observations with semi-analytical models of galaxy formation, we showed that ram-pressure is, from a statistical point of view, the main mechanism responsible for removing the cold hydrogen reservoir and quenching the star formation (see paper).  Thirdly, we obtained the first direct evidence for dust stripping associated to the removal of cold hydrogen in cluster galaxies, confirming the important role played by stripping in the enrichment of the intracluster medium (see paper).

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Dust and extinction in nearby galaxies. I showed that a significant fraction of the energy absorbed by dust originates from old stellar populations (and not from young stars), and thus standard UV star formation indicators overestimate the amount of new stars in galaxies. To correct for this important bias, I developed accurate recipes that have become a reference for the community (see paper), and which have been recently validated by studies based on the Herschel Space Observatory.

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Jelly-Fish galaxies. I discovered “Jelly-Fish” galaxies, a remarkable new `type’ of perturbed objects (see paper). These systems, in the process of falling for the first time into a cluster, show extraordinarily long tails of star clusters and star-forming regions which had never been seen before. This unexpected discovery demonstrated that star formation can be triggered in the stripped gas, with important consequences for environmental studies. Theoretically, it has allowed a crucial improvement in the modeling of gas cooling in numerical simulations. Observationally, it has triggered new surveys that have now showed how “Jelly Fish” galaxies represent a short, but crucial, snapshot in the evolution of cluster galaxies.

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Galaxy Pre-processing.  I found tantalizing evidence for the importance of group environment in galaxy evolution by discovering the first clear example of pre-processing in the local Universe (see paper). This has provided important constraints on the origin of lenticular galaxies.

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