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Title: Coevolution of Stars and Gas: Using an Analysis of Synthetic Observations to Investigate the Star–Gas Correlation in STARFORGE
Abstract

We explore the relation between stellar surface density and gas surface density (the star–gas, or S-G, correlation) in a 20,000Msimulation from the STAR FORmation in Gaseous Environments (starforge) project. We create synthetic observations based on the Spitzer and Herschel telescopes by modeling contamination by active galactic nuclei, smoothing based on angular resolution, cropping the field of view, and removing close neighbors and low-mass sources. We extract S-G properties such as the dense gas-mass fraction, the Class II:I ratio, and the S-G correlation (ΣYSOgas) from the simulation and compare them to observations of giant molecular clouds, young clusters, and star-forming regions, as well as to analytical models. We find that the simulation reproduces trends in the counts of young stellar objects and the median slope of the S-G correlation. This implies that the S-G correlation is not simply the result of observational biases, but is in fact a real effect. However, other statistics, such as the Class II:I ratio and dense gas-mass fraction, do not always match observed equivalents in nearby clouds. This motivates further observations covering the full simulation age range and more realistic modeling of cloud formation.

 
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NSF-PAR ID:
10479789
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
959
Issue:
2
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 135
Size(s):
["Article No. 135"]
Sponsoring Org:
National Science Foundation
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