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arXiv · 1911.02021

Cosmic Ray Driven Outflows from the Large Magellanic Cloud: Contributions to the LMC Filament

Chad Bustard·Ellen G. Zweibel·Elena D'Onghia·J. S. Gallagher III·Ryan Farber
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Abstract

In this paper, we build from previous work (Bustard et al. 2018) and present simulations of recent (within the past Gyr), magnetized, cosmic ray driven outflows from the Large Magellanic Cloud (LMC), including our first attempts to explicitly use the derived star formation history of the LMC to seed outflow generation. We run a parameter set of simulations for different LMC gas masses and cosmic ray transport treatments, and we make preliminary comparisons to published outflow flux estimates, neutral and ionized hydrogen observations, and Faraday rotation measure maps. We additionally report on the gas mass that becomes unbound from the LMC disk and swept by ram pressure into the Trailing Magellanic Stream. We find that, even for our largest outburst, the mass contribution to the Stream is still quite small, as much of the outflow-turned-halo gas is shielded on the LMC's far-side due to the LMC's primarily face-on infall through the Milky Way halo over the past Gyr. On the LMC's near-side, past outflows have fought an uphill battle against ram pressure, with near-side halo mass being at least a factor of a few smaller than the far-side. Absorption line studies probing only the LMC foreground, then, may be severely underestimating the total mass of the LMC halo formed by outflows.

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Chad Bustard, Ellen G. Zweibel, Elena D'Onghia, J. S. Gallagher III, Ryan Farber. 2020-04-27. Cosmic Ray Driven Outflows from the Large Magellanic Cloud: Contributions to the LMC Filament. https://doi.org/10.3847/1538-4357%2Fab7fa3

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