Contributed Talk - Splinter Stars

Wednesday, 15 September 2021, 17:35   (virtual Stars)

Supernova induced processing of interstellar dust: impact of ISM gas density and gas turbulence

Florian Kirchschlager
University College London (UCL)

Dust grains made of silicates, iron oxides and carbonaceous material are found throughout the interstellar medium (ISM). It is well established that evolved stars and supernovae (SNe) produce dust, but dust grains are also consumed in star formation or can be destroyed by shock waves from SNe. Quantifying the efficiency of dust destruction in the ISM due to SNe is crucial to understand galactic dust evolution. In this talk I will present 3D hydrodynamic simulations of an SN blast wave propagating through the ISM. The focus is on the late-stage evolution, which is dominated by the interaction between the forward shock and the surrounding ISM. This interaction leads to destruction of ISM dust from shock heated gas. The dust processing due to ion sputtering, accretion of atoms/molecules and grain-grain collisions is calculated in 2D slices from the simulation timeseries and the calculations are made with post-processing techniques using the Paperboats code. We find that efficiency of dust destruction depends strongly on the rate of grain shattering due to grain-grain collisions. With grain-grain collisions switched off the effective dust destruction is similar to previous theoretical estimates, but with grain shattering included the effective destruction efficiency is roughly one order of magnitude higher. This result is indicating that the dust destruction rate in the ISM may have been severely underestimated in previous work, which only worsens the dust-budget crises seen in galaxies at high redshifts.