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arXiv · 1610.02123

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

Carl L. Gardner·Jeremiah R. Jones·Evan Scannapieco·Rogier A. Windhorst
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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.

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Carl L. Gardner, Jeremiah R. Jones, Evan Scannapieco, Rogier A. Windhorst. 2016-12-09. Numerical Simulation of Star Formation by the Bow Shock of the Centaurus A Jet. https://doi.org/10.3847/1538-4357%2F835%2F2%2F232

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