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Title: Variations in the slope of the resolved star-forming main sequence: a tool for constraining the mass of star-forming regions
ABSTRACT The correlation between galaxies’ integrated stellar masses and star formation rates (the ‘star formation main sequence’, SFMS) is a well-established scaling relation. Recently, surveys have found a relationship between the star formation rate (SFR) and stellar mass surface densities on kpc and sub-kpc scales (the ‘resolved SFMS’, rSFMS). In this work, we demonstrate that the rSFMS emerges naturally in Feedback In Realistic Environments 2 (FIRE-2) zoom-in simulations of Milky Way-mass galaxies. We make SFR and stellar mass maps of the simulated galaxies at a variety of spatial resolutions and star formation averaging time-scales and fit the rSFMS using multiple methods from the literature. While the absolute value of the SFMS slope (αMS) depends on the fitting method, the slope is steeper for longer star formation time-scales and lower spatial resolutions regardless of the fitting method employed. We present a toy model that quantitatively captures the dependence of the simulated galaxies’ αMS on spatial resolution and use it to illustrate how this dependence can be used to constrain the characteristic mass of star-forming clumps.  more » « less
Award ID(s):
1715216 1652522
NSF-PAR ID:
10184321
Author(s) / Creator(s):
; ; ; ; ; ; ;
Date Published:
Journal Name:
Monthly Notices of the Royal Astronomical Society: Letters
Volume:
493
Issue:
1
ISSN:
1745-3925
Page Range / eLocation ID:
L87 to L91
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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