Faculty

  • Sandro Tacchella (산드로 따껠라)

  • Assistant Professor
  • Astrophysics
  • Current Research Interests

    Formation and Evolution of Galaxies

    Galaxies provide a unique laboratory to unravel a wide range of physical processes that rangefrom small to large scales, from star formation and stellar evolution to cosmological gas accretion and the large-scale cosmic web. The past two decades have been momentous in understanding the build-up of galaxies through most of cosmic time, especially in terms of their global properties and behavior. Today, the unknown physics of star formation and feedback represent the main uncertainty in our understanding of galaxy formation. Our research group is centered on understanding the physics that drives the internal workings of galaxies using strategies that connect the spatially resolved scales within galaxies to their global properties and cosmological environments through cosmic time. We adopt a multifaceted approach between theory and observations in order to shed new light onto the physics of galaxies, black holes and dark matter. In particular, we use forefront telescopes such as the Hubble Space Telescope and the upcoming James Webb Space Telescope to conduct observations of galaxies and – simultaneously – develop and analyze theoretical models to interpret our observations and draw inspiration for new observational enterprises.

    Research interests include
    – interplay between baryons, dark matter and black holes
    – observations of distant galaxies with the most advanced telescopes
    – development and analysis of analytical and numerical models of galaxy formation
    – formation of the first stars and galaxies in the early universe
    – evolution of the Milky Way galaxy

  • Biographical Sketch
    • 2021-present: Assistant Professor, Department of Physics, UNIST, Korea
    • 2017-2021: CfA Fellow, Harvard-Smithsonian Center for Astrophysics, USA
    • 2012-2017: Ph. D. in Physics, ETH Zurich, Switzerland
    • 2010-2012: M. Sc. in Physics, ETH Zurich, Switzerland
    • 2007-2010: B. Sc. in Physics, ETH Zurich, Switzerland
  • Selected Publications
    • Evidence for mature bulges and an inside-out quenching phase 3 billion years after the Big Bang, Tacchella, S., Carollo, C. M., Renzini, A., et al., 2015, Science, 348, 314
    • The confinement of star-forming galaxies into a main sequence through episodes of gas compaction, depletion and replenishment, Tacchella, S., Dekel, A., Carollo, C. M., et al., 2016, Monthly Notices of the Royal Astronomical Society, 457, 2790
    • Evolution of density profiles in high-z galaxies: compaction and quenching inside-out, Tacchella, S., Dekel, A., Carollo, C. M., et al., 2016, Monthly Notices of the Royal Astronomical Society, 458, 242
    • A redshift-independent efficiency model: star formation and stellar masses in dark matter halos at z>4, Tacchella, S., Bose, S., Conroy, C., et al., 2018, Monthly Notices of the Royal Astronomical Society, 868, 92
    • Dust attenuation, bulge Formation, and inside-out quenching of star formation in star-forming main sequence galaxies at z~2, Tacchella, S., Carollo, C. M., Forster Schreiber, N. M., et al., 2018, The Astrophysical Journal, 859, 56
    • Morphology and star formation in IllustrisTNG: the build-up of spheroids and discs, Tacchella, S., Diemer, B., Hernquist, L., et al., 2019, Monthly Notices of the Royal Astronomical Society, 487, 5416
    • Stochastic modelling of star-formation histories I: the scatter of the star-forming main sequence, Caplar, N., Tacchella, S., 2019, Monthly Notices of the Royal Astronomical Society, 487, 3845
    • Stochastic modelling of star-formation histories II: star-formation variability from molecular clouds and gas inflow, Tacchella, S., Forbes, J. C., Caplar, N., 2020, Monthly Notices of the Royal Astronomical Society, 497, 698
    • Rapid reionization by the oligarchs: the case for massive, UV-bright, star-forming galaxies with high escape fractions, Naidu, R. P, Tacchella, S., Mason, C. A., et al., 2020, The Astrophysical Journal, 892, 109
    • Degeneracies between baryons and dark matter: the challenge of constraining the nature of dark matter with JWST, Khimey, D., Bose, S., Tacchella, S., 2021, Monthly Notices of the Royal Astronomical Society, in press