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Title: The Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region (PHATTER). III. The Mass Function of Young Stellar Clusters in M33

We measure the star cluster mass function (CMF) for the Local Group galaxy M33. We use the catalog of stellar clusters selected from the Panchromatic Hubble Andromeda Treasury: Triangulum Extended Region survey. We analyze 711 clusters in M33 with7.0<log(Age/yr)<8.5, and log(M/M) > 3.0 as determined from color–magnitude diagram fits to individual stars. The M33 CMF is best described by a Schechter function with power-law slopeα= −2.060.13+0.14, and truncation mass log(Mc/M)=4.240.13+0.16. The data show strong evidence for a high-mass truncation, thus strongly favoring a Schechter function fit over a pure power law. M33's truncation mass is consistent with the previously identified linear trend betweenMc, and star formation rate surface density, ΣSFR. We also explore the effect that individual cluster mass uncertainties have on derived mass function parameters, and find evidence to suggest that large cluster mass uncertainties have the potential to bias the truncation mass of fitted mass functions at the 1σlevel.

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Award ID(s):
1757792 2149425
Publication Date:
Journal Name:
The Astrophysical Journal
Page Range or eLocation-ID:
Article No. 15
DOI PREFIX: 10.3847
Sponsoring Org:
National Science Foundation
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