The IRX-$\beta$ relation of high-redshift galaxies

Understand

The relation between infrared excess (IRX) and UV spectral slope ($\beta_{\rm UV}$) is an empirical probe of dust properties of galaxies.

• The shape, scatter, and redshift evolution of this relation are not well understood, however, leading to uncertainties in estimating the dust content and star formation rates (SFRs) of galaxies at high redshift.
• In this study, we explore the nature and properties of the IRX-$\beta_{\rm UV}$ relation with a sample of $z=2-6$ galaxies ($M_*\approx 10^9-10^{12}\,M_\odot$) extracted from high-resolution cosmological simulations (MassiveFIRE) of the Feedback in Realistic Environments (FIRE) project.
• The galaxies in our sample show an IRX-$\beta_{\rm UV}$ relation that is in good agreement with the observed relation in nearby galaxies.