English

The MAGPI Survey: Evidence for Non-Universal Resolved Dust Attenuation Relations Beyond the Local Universe

Astrophysics of Galaxies 2026-07-08 v1

Abstract

We study the spatially resolved relation between dust attenuation (AVA_V) and star formation rate surface density (ΣSFR\Sigma_{\mathrm{SFR}}) in galaxies from the MAGPI survey (0.25<z<0.420.25 < z < 0.42). Using Balmer-decrement-based attenuation maps for 178 galaxies, we investigate whether the locally calibrated resolved AVA_V--ΣSFR\Sigma_{\mathrm{SFR}} relation remains valid at intermediate redshift by comparing MAGPI with the local relation measured from MaNGA. We find a clear positive correlation between AVA_V and ΣSFR\Sigma_{\mathrm{SFR}} in MAGPI, with systematically higher attenuation than in MaNGA at fixed ΣSFR\Sigma_{\mathrm{SFR}}. After matching galaxies in stellar mass (MM_{*}) and offset from the star-forming main sequence (Δ\DeltaSFMS), MAGPI galaxies remain more attenuated than MaNGA galaxies at fixed ΣSFR\Sigma_{\mathrm{SFR}}. The attenuation excess is strongest for galaxies below the SFMS (ΔAV0.40\Delta A_V \sim 0.40 mag), weaker for galaxies on the SFMS (ΔAV0.28\Delta A_V \sim 0.28 mag), and minimal for galaxies above the SFMS (ΔAV0.07\Delta A_V \sim 0.07 mag). The dependence of the offset on Δ\DeltaSFMS suggests that nebular attenuation on kpc scales is regulated not only by local star formation activity, but also by the global evolutionary state of the host galaxy. Together, these results indicate that the resolved AVA_V--ΣSFR\Sigma_{\mathrm{SFR}} relation is not universal, and that locally calibrated attenuation relations may not fully describe galaxies at intermediate redshift. This highlights the need for attenuation calibrations that account for galaxy population and redshift when interpreting spatially resolved galaxy properties.

Keywords

Cite

@article{arxiv.2607.07122,
  title  = {The MAGPI Survey: Evidence for Non-Universal Resolved Dust Attenuation Relations Beyond the Local Universe},
  author = {A. Mailvaganam and T. Zafar and P. Corcho-Caballero and S. Salim and Y. Koyama and K. E. Harborne and C. D. P. Lagos and J. T. Mendel and E. Wisnioski and I. U. Aalia and S. Ayyappan and S. Barsanti and A. J. Battisti and J. Bland-Hawthorn and I. Breda and S. Carlson and Q. -H. Chen and B. Courtney-Barrer and S. M. Croom and S. Ellis and C. Foster and E. Gjergo and K. Grasha and S. Gurung-Lopez and S. Mobina Hosseini and S. Jeon and X. Lyu and T. Mukherjee and M. Mun and Hye-Jin Park and Y. Peng and L. A. Porta and J. Prathap and A. Raidani and R. S. Remus and B. S. Salmasi and G. Sharma and Sarah M. Sweet and Dian P. Triani and L. M. Valenzuela and G. van de Ven and Bodo L. Ziegler},
  journal= {arXiv preprint arXiv:2607.07122},
  year   = {2026}
}