Dust destruction by the supernova remnant forward shock in a turbulent interstellar medium

TL;DR

This work addressing whether supernova remnants net-destroy or produce dust combines high-resolution 3D turbulence-driven ISM simulations with 3D MHD SNR evolution and detailed post-processing dust physics. The approach captures how forward shocks interact with a realistically turbulent medium, including gas/plasma drag, sputtering, and grain-grain collisions for silicate and carbonaceous dust. Key findings show destruction fractions of $27$–$92\%$ within the first $10\ \mathrm{kyr}$, with filaments shielding dust but not sufficiently to reverse the net-destruction trend; carbonaceous grains survive somewhat better than silicates, and higher densities yield the largest destroyed dust masses. The results indicate that SNRs, under the explored conditions, are net dust destroyers, highlighting the importance of ISM structure and turbulence in shaping the dust budget during early SNR evolution and motivating future work to include pre-SN feedback and ejecta evolution for a complete budget.

Abstract

Context. While supernova remnants (SNRs) are observed to produce up to 1 M$_\odot$ of dust, the amount of dust destroyed by the forward shock (FS) is poorly constrained, raising the question whether they are net dust producers or destroyers. Aims. We aim to estimate the dust destruction efficiency of SNR FSs in a realistically turbulent interstellar medium (ISM) during their most destructive phase, and assess dust shielding by high density filaments during this period. Methods. We run 3D turbulence simulations for different turbulent Mach numbers (0-3) and average ISM densities (1-100 cm$^{-3}$) to resemble observations of the turbulent ISM. We then set off a supernova to trace its 3D magnetohydrodynamical evolution for 10 kyr. Finally, we run post-processing simulations to study the dust transport and destruction by the SNR FS, considering gas and plasma drag, kinetic and thermal sputtering, and grain-grain collisions, and either silicate or carbonaceous dust. Results. The dust destruction rate of the FS strongly depends on the average ISM density and turbulence strength, varying between 27-92% (0.85-11.0 M$_\odot$) in the studied 10 kyr. Overall, dust is less efficiently destroyed in a low density medium (1 cm$^{-3}$, 27-57%) than in intermediate (10 cm$^{-3}$, 46-92%) and high densities (100 cm$^{-3}$, 73-87%). The FS destroys 8-34% less dust in high Mach turbulence compared to a homogeneous medium. Furthermore, carbonaceous grains are more robust (up to 21% more) than silicates. Conclusions. Filaments can partly shield dust from destruction in the first 10 kyr, however, always more than 0.85 M$_\odot$ of dust is destroyed, making most SNRs dust sinks under the conditions explored in this work. The destruction efficiency of the SNRs with less than 1 M$_\odot$ of destroyed dust has not yet plateaued so that they are most likely also net dust destroyers by the end of their lifetime.

Figures (14)

• Figure 1: Structural comparison of the dust distribution in a turbulence snapshot of our intermediate density ([10]cm$^{-3}$) supersonic turbulence ($\mathcal{M}=3$) simulation (left) and an observed SPIRE [250]$\muup$m dust map from Herschel observations of the Polaris Flare Miville-Deschenes2010$^{\ref{['footnote1']}}$, which has a Mach number of $\mathcal{M}=2$--10 Beattie2019. The physical length scale of [$20\times20$]pc of the observed ISM is based on the distance of [350]pc to the Polaris Flare Schlafly2014Panopoulou2022.
• Figure 2: Density PDFs of the different turbulent Mach numbers $\mathcal{M}$ in the converged low density ([1]cm$^{-3}$) turbulence simulations. With a higher turbulent Mach number, cell densities ($\rho$) can have a larger deviation from the average density <$\rho$>.
• Figure 3: Number densities of the $z=0$ slice of all simulations carried out in this paper at [10]kyr. This includes different average ISM number densities ($n$) and turbulent Mach numbers ($\mathcal{M}$). The colorbar scales are consistent in each of the average ISM number density cases but the box sizes can vary between [20 or 40]pc.
• Figure 4: Dust destruction efficiencies (left $y$-axis) and masses (right $y$-axis) in the $z=0$ slice. This destruction efficiency refers to the ratio between the destroyed dust mass at each time step to the total encountered dust mass at the last considered snapshot. Different Mach numbers of $\mathcal{M}=0,0.3,1,\text{ and }3$, and average ISM densities of $\unit[n=1,10,\text{ and }100]{cm^{-3}}$ are shown. For each Mach number and ISM density parameter set, 4 different dust simulations were carried out, including either silicate (Sil) or carbonaceous (Car) dust, and either grain-grain collisions and sputtering (gg+sp) or only sputtering (sp).
• Figure 5: [$16\times16$]pc zoom-in on a filament of the $n=\unit[1]{cm^{-3}}$ and $\mathcal{M}=1$ simulation at $t=\unit[0]{yr}$ and $t=\unit[10]{kyr}$. The filament cannot withstand the shock efficiently but is destroyed leaving behind finger like structures that arise from the forward shock front into the SNR interior. Furthermore, some high density cloudlets are formed, as circled in the image. The arrow indicates the approximate direction of the forward shock.