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arXiv · 1701.00024

Numerical Simulations of a Jet-Cloud Collision and Starburst: Application to Minkowski's Object

Abstract

We present results of three-dimensional, multi-physics simulations of an AGN jet colliding with an intergalactic cloud. The purpose of these simulations is to assess the degree of "positive feedback," i.e. jet-induced star formation, that results. We have specifically tailored our simulation parameters to facilitate comparison with recent observations of Minkowski's Object (M.O.), a stellar nursery located at the termination point of a radio jet coming from galaxy NGC 541. As shown in our simulations, such a collision triggers shocks which propagate around and through the cloud. These shocks condense the gas and under the right circumstances may trigger cooling instabilities, creating runaway increases in density, to the point that individual clumps can become Jeans unstable. Our simulations provide information about the expected star formation rate, total mass converted to \ion{H}{1}, H$_2$, and stars, and the relative velocity of the stars and gas. Our results confirm the possibility of jet-induced star formation, and agree well with the observations of M.O.

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P. Chris Fragile, Peter Anninos, Steve Croft, Mark Lacy, Jason W. L. Witry. 2017-10-26. Numerical Simulations of a Jet-Cloud Collision and Starburst: Application to Minkowski's Object. https://doi.org/10.3847/1538-4357%2Faa95c6

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