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arXiv · 1903.05104

The CARMA-NRO Orion Survey: Statistical Signatures of Feedback in the Orion A Molecular Cloud

Jesse R. Feddersen·Héctor G. Arce·Shuo Kong·Volker Ossenkopf-Okada·John M. Carpenter
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Abstract

We investigate the relationship between turbulence and feedback in the Orion A molecular cloud using maps of $^{12}$CO(1-0), $^{13}$CO(1-0) and C$^{18}$O(1-0) from the CARMA-NRO Orion survey. We compare gas statistics with the impact of feedback in different parts of the cloud to test whether feedback changes the structure and kinematics of molecular gas. We use principal component analysis, the spectral correlation function, and the spatial power spectrum to characterize the cloud. We quantify the impact of feedback with momentum injection rates of protostellar outflows and wind-blown shells as well as the surface density of young stars. We find no correlation between shells or outflows and any of the gas statistics. However, we find a significant anti-correlation between young star surface density and the slope of the $^{12}$CO spectral correlation function, suggesting that feedback may influence this statistic. While calculating the principal components, we find peaks in the covariance matrix of our molecular line maps offset by 1-3 km s$^{-1}$ toward several regions of the cloud which may be produced by feedback. We compare these results to predictions from molecular cloud simulations.

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Jesse R. Feddersen, Héctor G. Arce, Shuo Kong, Volker Ossenkopf-Okada, John M. Carpenter. 2019-03-12. The CARMA-NRO Orion Survey: Statistical Signatures of Feedback in the Orion A Molecular Cloud. https://doi.org/10.3847/1538-4357%2Fab0e7d

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