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arXiv · 2109.06916

Robustness of Synthetic Observations in Producing Observed Core Properties: Predictions for the TolTEC Clouds to Cores Legacy Survey

Abstract

We use hydrodynamical simulations of star-forming gas with stellar feedback and sink particles (proxies for young stellar objects, i.e., YSOs) to produce and analyze synthetic 1.1mm continuum observations at different distances (150 - 1000pc) and ages (0.49 - 1.27 Myr). We characterize how the inferred core properties, including mass, size, and clustering with respect to diffuse natal gas structure, change with distance, cloud evolution, and the presence of YSOs. We find that atmospheric filtering and core segmentation treatments have distance-dependent impacts on the resulting core properties for d < 300pc and 500pc, respectively, which dominate over evolutionary differences. Concentrating on synthetic observations at further distances (650-1000pc), we find a growing separation between the inferred sizes and masses of cores with and without YSOs in the simulations, which is not seen in recent observations of the Mon R2 cloud at 860pc. We find that the synthetic cores cluster in smaller groups, and their mass densities are correlated with gas column density over a much narrower range, than the Mon R2 observations. Such differences limit applicability of the evolutionary predictions we report here and motivate future efforts to adapt our synthetic observation and analysis framework to next generation simulations such as STARFORGE. These predictions and systematic characterizations will help guide analysis of cores for the upcoming TolTEC Clouds to Cores Legacy Survey on the Large Millimeter Telescope Alfonso Serrano (LMT).

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BibTeXRIS

S. K. Betti, R. Gutermuth, S. Offner, G. Wilson, A. Sokol, R. Pokhrel. 2021-09-14. Robustness of Synthetic Observations in Producing Observed Core Properties: Predictions for the TolTEC Clouds to Cores Legacy Survey. https://doi.org/10.3847/1538-4357/ac2666

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