The faint outskirts of the blue compact galaxy Haro 11: is there a red excess?

TL;DR

This study presents deep V and K band observations of Haro 11, revealing a less extreme V-K color that aligns with typical stellar populations, challenging previous claims of an abnormally red host galaxy.

Contribution

The paper provides the deepest V and K band imaging of Haro 11, offering a revised V-K color measurement that resolves previous discrepancies with stellar population models.

Findings

Revised V-K color of 2.3+-0.2 for Haro 11's host

Previous red color measurements were likely overestimated

Host galaxy's color is consistent with standard stellar populations

Abstract

Previous studies of the low surface brightness host of the blue compact galaxy (BCG) Haro 11 have suggested an abnormally red color of V-K=4.2+-0.8 for the host galaxy. This color is inconsistent with any normal stellar population over a wide range of stellar metallicities (Z=0.001-0.02). Similar though less extreme host colors have been measured for other BCGs and may be reconciled with population synthesis models, provided that the stellar metallicity of the host is higher than that of the ionized gas in the central starburst. We present the deepest V and K band observations to date of Haro 11 and derive a new V-K color for the host galaxy. Our new data suggest a far less extreme colour of V-K=2.3+-0.2, which is perfectly consistent with the expectations for an old host galaxy with the same metallicty as that derived from nebular emission lines in the star-forming center.