Evolutie van sterrenstelsels achter de schermen: stof attenuatie in kaart brengen en begrijpen

01-10-2018 → 14-12-2020
Fonds voor Wetenschappelijk Onderzoek - Vlaanderen (FWO)
  • Natural sciences
    • Astronomy and space sciences

Galaxies continuously convert hydrogen gas into heavier elements through the creation and
evolution of stars. An important tool to quantitatively study the evolution of the elements that
make up the Universe is to measure the star formation rate over time. However, this
measurement is considerably complicated by the presence of dust grains intermixed with the gas.
Dust obscures on average one third of the stellar radiation, making it difficult, for instance, to
count newborn stars. It is thus particularly important that we understand how strong the
attenuating effect of dust is on our observations of galaxies. Standard dust corrections rely on
simplified, average attenuation formulae. The new generation of spectrographs can actually map
the light of galaxies both spatially and spectrally at high resolution. This is a goldmine for in-depth
studies of both stars and dust.
We propose to gather the data described above for a large set of nearby galaxies, where dust is
also already directly observed in emission. This unique dataset, and new, state-of-the-art
modelling of the spectra, will enable us to quantify the dust attenuation in unprecedented detail.
Doing this for a wide range of galaxies will enable us to accurately measure star formation behind
the curtain of dust obscuration. With these new insights, we will position our institute in the
vanguard to analyse data from new telescopes such as the upcoming JWST, probing galaxies across
the universe until the cosmic dawn.