Showing papers by "Christopher J. Wareing published in 2021"
TL;DR: In this paper, the authors performed hydrodynamic simulations of the interaction of a shock with a molecular cloud evolving due to thermal instability (TI) and gravity, and showed that the resulting clump-clump collisions and mergers accelerated the global collapse of the clouds.
Abstract: Using the adaptive mesh refinement code MG, we perform hydrodynamic simulations of the interaction of a shock with a molecular cloud evolving due to thermal instability (TI) and gravity. To explore the relative importance of these processes, three case studies are presented. The first follows the formation of a molecular cloud out of an initially quiescent atomic medium due to the effects of TI and gravity. The second case introduces a shock whilst the cloud is still in the warm atomic phase, and the third scenario introduces a shock once the molecular cloud has formed. The shocks accelerate the global collapse of the clouds with both experiencing local gravitational collapse prior to this. When the cloud is still atomic, the evolution is shock dominated and structures form due to dynamical instabilities within a radiatively cooled shell. While the transmitted shock can potentially trigger the TI, this is prevented as material is shocked multiple times on the order of a cloud-crushing time-scale. When the cloud is molecular, the post-shock flow is directed via the pre-existing structure through low-density regions in the inter-clump medium. The clumps are accelerated and deformed as the flow induces clump–clump collisions and mergers that collapse under gravity. For a limited period, both shocked cases show a mixture of Kolmogorov and Burgers turbulence-like velocity and logarithmic density power spectra, and strongly varying density spectra. The clouds presented in this work provide realistic conditions that will be used in future feedback studies.
6 citations
TL;DR: In this paper, the authors investigated the numerical resolution needed to inflate an energy-driven stellar wind bubble in an external medium and found that the radius of the wind injection region must be below a maximum value, $r_{\rm inj,max}$, in order for a bubble to be produced, but must be significantly below this value if the bubble properties are to closely agree with analytical predictions.
Abstract: Stellar winds are one of several ways that massive stars can affect the star formation process on local and galactic scales. In this paper we investigate the numerical resolution needed to inflate an energy-driven stellar wind bubble in an external medium. We find that the radius of the wind injection region, $r_{\rm inj}$, must be below a maximum value, $r_{\rm inj,max}$, in order for a bubble to be produced, but must be significantly below this value if the bubble properties are to closely agree with analytical predictions. The final bubble momentum is within 25 per cent of the value from a higher resolution reference model if $\chi = r_{\rm inj}/r_{\rm inj,max}$ = 0.1. Our work has significance for the amount of radial momentum that a wind-blown bubble can impart to the ambient medium in simulations, and thus on the relative importance of stellar wind feedback.
2 citations
Posted Content•
TL;DR: In this article, the authors investigate the resolution requirements to inflate a stellar wind bubble in an external medium, and find that the radius of the wind injection region must be below a maximum value, and must be significantly below this value if the bubble is to be modelled correctly.
Abstract: Stellar winds are one of several ways that massive stars can affect the star formation process on local and galactic scales. In this paper we investigate the resolution requirements to inflate a stellar wind bubble in an external medium. We find that the radius of the wind injection region, $r_{\rm inj}$, must be below a maximum value, $r_{\rm inj,max}$, in order for a bubble to be produced, but must be significantly below this value if the bubble is to be modelled correctly. Our work has significance for the amount of radial momentum that a wind-blown bubble can impart to the ambient medium in simulations, and thus on the relative importance of stellar wind feedback.
Posted Content•
TL;DR: In this article, the authors investigated the numerical resolution needed to inflate an energy-driven stellar wind bubble in an external medium and found that the radius of the wind injection region must be below a maximum value, $r_{\rm inj,max}$, in order for a bubble to be produced, but must be significantly below this value if the bubble properties are to closely agree with analytical predictions.
Abstract: Stellar winds are one of several ways that massive stars can affect the star formation process on local and galactic scales. In this paper we investigate the numerical resolution needed to inflate an energy-driven stellar wind bubble in an external medium. We find that the radius of the wind injection region, $r_{\rm inj}$, must be below a maximum value, $r_{\rm inj,max}$, in order for a bubble to be produced, but must be significantly below this value if the bubble properties are to closely agree with analytical predictions. The final bubble momentum is within 25 per cent of the value from a higher resolution reference model if $\chi = r_{\rm inj}/r_{\rm inj,max}$ = 0.1. Our work has significance for the amount of radial momentum that a wind-blown bubble can impart to the ambient medium in simulations, and thus on the relative importance of stellar wind feedback.