Scylla VI: Parsec-Scale Dust Extinction Maps in the SMC and LMC
Abstract
We present a novel methodology for mapping dust extinction in nearby galaxies at parsec-scale resolution. We apply it to HST 68 fields within the Small and Large Magellanic Clouds (23 fields in the SMC and 45 fields in the LMC) using multi-band HST photometry from the Scylla and METAL surveys. Our technique leverages \textit{kriging}, a geostatistical interpolation method built on the principles of Gaussian Process regression, combined with Gaussian mixture modeling to statistically isolate background stellar sources and account for line-of-sight depth effects. 3D dust simulations demonstrate the method's capability to recover column densities to an accuracy of mag in fields with at least 1000 sources. The resulting resolution (-pc) dust maps reveal detailed structure and strong spatial correlation with ancillary ISM tracers, especially in star-forming regions like 30 Doradus. Global extinction of total column densities follows log-normal profiles in both galaxies, with the SMC exhibiting slightly higher mean extinction ( mag) than the broader LMC ( mag), likely due to significant line-of-sight depths. We find systematic offsets between dust mass surface densities () derived from extinction versus FIR emission in both galaxies, with ratios ranging from . This work provides the highest-resolution dust extinction maps in SMC and LMC to date, which offer a vital independent benchmark for constraining dust emissivity, -dark gas fractions, and the multi-scale structure of the ISM in low-metallicity environments.
Keywords
Cite
@article{arxiv.2605.06925,
title = {Scylla VI: Parsec-Scale Dust Extinction Maps in the SMC and LMC},
author = {Christina W. Lindberg and Claire E. Murray and Christopher J. R. Clark and Caroline Bot and Clare Burhenne and Yumi Choi and Roger E. Cohen and Steven R. Goldman and Karl D. Gordon and Kristen B. W. McQuinn and Julia Roman-Duval and Karin M. Sandstrom and Edward F. Schlafly and Elizabeth Tarantino and Benjamin F. Williams and Petia Yanchulova Merica-Jones and Catherine Zucker},
journal= {arXiv preprint arXiv:2605.06925},
year = {2026}
}
Comments
28 pages, 14 figures, accepted to ApJ