Article

Implications of a Temperature-dependent Initial Mass Function. II. An Updated View of the Star-forming Main Sequence

Charles L. SteinhardtCosmic Dawn Center (DAWN), DenmarkAlbert SneppenCosmic Dawn Center (DAWN), DenmarkBasel MostafaCalifornia Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USAHagan HensleyCalifornia Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USAAdam S. JermynCenter for Computational Astrophysics, Flatiron Institute, New York, NY 10010, USAAdrian LopezCalifornia Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USAJ. R. WeaverCosmic Dawn Center (DAWN), DenmarkGabriel BrammerCosmic Dawn Center (DAWN), DenmarkThomas H. ClarkCalifornia Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USAI. DavidzonCosmic Dawn Center (DAWN), DenmarkAndrei DiaconuCalifornia Institute of Technology, 1200 E. California Blvd., Pasadena, CA 91125, USAB. MobasherUniversity of California, Riverside, 900 University Ave. Riverside, CA 92521, USAVadim RusakovCosmic Dawn Center (DAWN), DenmarkSune ToftCosmic Dawn Center (DAWN), Denmark

2022en

ABI

Abstract

Abstract The stellar initial mass function (IMF) is predicted to depend upon the temperature of gas in star-forming molecular clouds. The introduction of an additional parameter, T IMF , into photometric template fitting, allows galaxies to be fit with a range of IMFs. Three surprising new features appear: (1) most star-forming galaxies are best fit with a bottom-lighter IMF than the Milky Way; (2) most star-forming galaxies at fixed redshift are fit with a very similar IMF; and (3) the most-massive star-forming galaxies at fixed redshift instead exhibit a less bottom-light IMF, similar to that measured in quiescent galaxies. Additionally, since stellar masses and star formation rates both depend on the IMF, these results slightly modify the resulting relationship, while yielding similar qualitative characteristics to previous studies.

Identifiers

DOI: 10.3847/1538-4357/ac62d6

Citations and references

Cited by 10 references

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