Numerical Simulation of Star Formation by the Bow Shock of the Centaurus A Jet

TL;DR

This paper uses 3D numerical simulations to investigate how the bow shock from the Centaurus A jet can trigger star formation in molecular clouds, aligning with recent HST observations.

Contribution

It introduces a detailed simulation approach to demonstrate jet-induced star formation, confirming observational hypotheses with quantitative results.

Findings

Star clusters form in bow-shocked clouds with densities > 40 H2/cm^3

Approximately 20 star clusters of 10^4 M_sun form in a typical cloud

Simulation results match HST observations of star formation in Cen A

Abstract

Recent Hubble Space Telescope (HST) observations of the extragalactic radio source Centaurus A (Cen A) display a young stellar population around the southwest tip of the inner filament 8.5 kpc from the Cen A galactic center, with ages in the range of 1-3 Myr. Crockett et al. (2012) argue that the transverse bow shock of the Cen A jet triggered this star formation as it impacted dense molecular cores of clouds in the filament. To test this hypothesis, we perform three-dimensional numerical simulations of induced star formation by the jet bow shock in the inner filament of Cen A, using a positivity preserving WENO method to solve the equations of gas dynamics with radiative cooling. We find that star clusters form inside a bow-shocked molecular cloud when the maximum initial density of the cloud is > 40 H2 molecules/cm^3. In a typical molecular cloud of mass 10^6 M_sun and diameter 200 pc, approximately 20 star clusters of mass 10^4 M_sun are formed, matching the HST images.