Genesis and evolution of dust in galaxies in the early Universe II. Rapid dust evolution in quasars at z > 6

Understand

We assess the most plausible scenarios for generating large amounts of dust in high-z quasars (QSOs) on the basis of observationally derived physical properties of QSOs at z > 6.

• We use a chemical evolution model to compute the temporal progression of quantities, such as the amount of dust and gas, stellar masses, star formation rates (SFRs) and the metallicity for various combinations of the initial mass function (IMF), the mass of the galaxy, dust production efficiencies, and the degree of dust destruction in the ISM.
• We investigate the influence of the SFR on the evolution of these quantities, and determine the earliest epochs at which agreement with observations can be achieved.
• We apply the obtained results to individual QSOs at z > 6.