The young stellar population of NGC 4214 as observed with HST. II. Results

TL;DR

This study uses HST UV-optical imaging to analyze the stellar populations, extinction, and cluster properties of NGC 4214, revealing patchy dust, a consistent blue-to-red supergiant ratio, and a steep IMF in the field.

Contribution

It provides detailed observational results on NGC 4214's stellar populations, extinction, and cluster ages, with new insights into the IMF and supergiant ratios at its metallicity.

Findings

Patchy stellar extinction across the galaxy.

Blue-to-red supergiant ratio matches theoretical models.

Field IMF is steeper than Salpeter.

Abstract

We present the results of a detailed UV-optical study of the nearby dwarf starburst galaxy NGC 4214 using multifilter HST/WFPC2+STIS photometry. The stellar extinction is found to be quite patchy, with some areas having values of E(4405-5495)< 0.1 mag and others, associated with star forming regions, much more heavily obscured, a result which is consistent with previous studies of the nebular extinction. We determined the ratio of blue-to-red supergiants and found it to be consistent with theoretical models for the metallicity of the SMC. The stellar IMF of the field in the range 20-100 solar masses is found to be steeper than Salpeter. A number of massive clusters and associations with ages between a few and 200 million years are detected and their properties are discussed.