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arXiv · 2305.06388

Dust Properties of 870 Micron Selected Galaxies in the GOODS-S

S. J. McKay·A. J. Barger·L. L. Cowie·F. E. Bauer·M. J. Nicandro Rosenthal
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Abstract

We analyze the dust properties of 57 870 $\mu$m selected dusty star-forming galaxies in the GOODS-S using new deep ALMA 1.2 mm, 2 mm, and 3 mm continuum imaging together with other far-infrared through millimeter data. We fit the spectral energy distributions (SEDs) with optically thin modified blackbodies to constrain the emissivity indices and effective dust temperatures, finding a median emissivity index of $\beta = 1.78^{+0.43}_{-0.25}$ and a median temperature of $T_d = 33.6^{+12.1}_{-5.4}$ K. We observe a negative correlation between $\beta$ and $T_d$. By testing several SED models, we determine that the derived emissivity indices can be influenced by opacity assumptions. Our temperature measurements are consistent with no evolution in dust temperature with redshift.

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S. J. McKay, A. J. Barger, L. L. Cowie, F. E. Bauer, M. J. Nicandro Rosenthal. 2023-05-10. Dust Properties of 870 Micron Selected Galaxies in the GOODS-S. https://doi.org/10.3847/1538-4357%2Facd1e5

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