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1. Dust Temperature Uncertainties Hamper the Inference of Dust and Molecular Gas Masses from the Dust Continuum Emission of Quiescent High-redshift Galaxies

   https://doi.org/10.3847/2041-8213/ac951d  

   Cochrane, R. K. ; Hayward, C. C. ; Anglés-Alcázar, D. ( November 2022 , The Astrophysical Journal Letters)

   Single flux density measurements at observed-frame submillimeter and millimeter wavelengths are commonly used to probe dust and gas masses in galaxies. In this Letter, we explore the robustness of this method to infer dust mass, focusing on quiescent galaxies, using a series of controlled experiments on four massive halos from the Feedback in Realistic Environments project. Our starting point is four star-forming central galaxies at seven redshifts betweenz= 1.5 andz= 4.5. We generate modified quiescent galaxies that have been quenched for 100 Myr, 500 Myr, or 1 Gyr prior to each of the studied redshifts by reassigning stellar ages. We derive spectral energy distributions for each fiducial and modified galaxy using radiative transfer. We demonstrate that the dust mass inferred is highly dependent on the assumed dust temperature,T_dust, which is often unconstrained observationally. Motivated by recent work on quiescent galaxies that assumedT_dust∼ 25 K, we show that the ratio between dust mass and 1.3 mm flux density can be higher than inferred by up to an order of magnitude, due to the considerably lower dust temperatures seen in non-star-forming galaxies. This can lead to an underestimation of dust mass (and, when submillimeter flux density is used as a proxy for molecular gas content and gas mass). This underestimation is most severe at higher redshifts, where the observed-frame 1.3 mm flux density probes rest-frame wavelengths far from the Rayleigh–Jeans regime, and hence depends superlinearly on dust temperature. We fit relations between ratios of rest-frame far-infrared flux densities and mass-weighted dust temperature that can be used to constrain dust temperatures from observations and hence derive more reliable dust and molecular gas masses.

    

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2. Improved Parameterization for the Size Distribution of Emitted Dust Aerosols Reduces Model Underestimation of Super Coarse Dust

   https://doi.org/10.1029/2021GL097287  

   Meng, Jun ; Huang, Yue ; Leung, Danny M. ; Li, Longlei ; Adebiyi, Adeyemi A. ; Ryder, Claire L. ; Mahowald, Natalie M. ; Kok, Jasper F. ( April 2022 , Geophysical Research Letters)
3. X-ray Spectroscopic Quantification of Phosphorus Transformation in Saharan Dust during Trans-Atlantic Dust Transport

   https://doi.org/10.1021/acs.est.1c01573  

   Dam, Than T. ; Angert, Alon ; Krom, Michael D. ; Bigio, Laura ; Hu, Yongfeng ; Beyer, Kevin A. ; Mayol-Bracero, Olga L. ; Santos-Figueroa, Gilmarie ; Pio, Casimiro ; Zhu, Mengqiang ( September 2021 , Environmental Science & Technology)
4. Uranium isotopes of aeolian dust deposited in northern Tibetan Plateau glaciers: Implications for tracing aeolian dust provenance

   https://doi.org/10.1016/j.fmre.2022.01.026  

   Jiao, Xiaoyu ; Dong, Zhiwen ; Brahney, Janice ; Parteli, Eric J.R. ; Li, Fangzhou ; Marcelli, Augusto ; Wei, Ting ( February 2022 , Fundamental Research)
5. How Well Can We Measure Galaxy Dust Attenuation Curves? The Impact of the Assumed Star-dust Geometry Model in Spectral Energy Distribution Fitting

   https://doi.org/10.3847/1538-4357/ac6959  

   Lower, Sidney ; Narayanan, Desika ; Leja, Joel ; Johnson, Benjamin D. ; Conroy, Charlie ; Davé, Romeel ( May 2022 , The Astrophysical Journal)

   Abstract One of the most common methods for inferring galaxy attenuation curves is via spectral energy distribution (SED) modeling, where the dust attenuation properties are modeled simultaneously with other galaxy physical properties. In this paper, we assess the ability of SED modeling to infer these dust attenuation curves from broadband photometry, and suggest a new flexible model that greatly improves the accuracy of attenuation curve derivations. To do this, we fit mock SEDs generated from the simba cosmological simulation with the prospector SED fitting code. We consider the impact of the commonly assumed uniform screen model and introduce a new nonuniform screen model parameterized by the fraction of unobscured stellar light. This nonuniform screen model allows for a nonzero fraction of stellar light to remain unattenuated, resulting in a more flexible attenuation curve shape by decoupling the shape of the UV attenuation curve from the optical attenuation curve. The ability to constrain the dust attenuation curve is significantly improved with the use of a nonuniform screen model, with the median offset in UV attenuation decreasing from −0.30 dex with a uniform screen model to −0.17 dex with the nonuniform screen model. With this increase in dust attenuation modeling accuracy, we also improve the star formation rates (SFRs) inferred with the nonuniform screen model, decreasing the SFR offset on average by 0.12 dex. We discuss the efficacy of this new model, focusing on caveats with modeling star-dust geometries and the constraining power of available SED observations. 

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