Super Star Clusters in SBS0335-052E

TL;DR

This study uses high-resolution images to analyze the structure, star formation history, and environment of super star clusters in the low-metallicity galaxy SBS0335-052E, revealing bi-modal star formation and potential for planet formation.

Contribution

It provides new measurements of SSC sizes, identifies bi-modal star formation regions, and locates H2 emission, offering insights into star formation processes in low-metallicity environments.

Findings

Star formation is bi-modal with compact and extended regions.

Two extended regions are less than 10 million years old.

H2 emission is located in but not at the centers of SSCs.

Abstract

As one of the lowest metallicity star forming galaxies, with a nucleus of several super star clusters, SBS0335-052E is the subject of substantial current study. We present new insights on this galaxy based on new and archival high spatial resolution NICMOS and ACS images. We provide new measurements and limits on the size of several of the SSCs. The images have sufficient resolution to divide the star formation into compact regions and newly discovered extended regions, indicating a bi-modal form of star formation. The star formation regions are dated via the equivalent width of the Pa alpha emission and we find that two of the extended regions of star formation are less than 10 million years old. Our previous finding that stellar winds confine the photo-ionizing flux to small regions around individual stars is consistent with the new observations. This may allow planet formation in what would traditionally be considered a harsh environment and has implications for the number of planets around globular cluster stars. In addition the images pinpoint the regions of H2 emission as located in, but not at the center of the two star forming super star clusters, S1 and S2.