PopIII-star siblings in IZw18 and WRs in metal-poor galaxies unveiled from integral field spectroscopy

TL;DR

This study uses integral field spectroscopy to analyze extremely metal-poor galaxies, revealing the importance of aperture effects and identifying potential PopIII-star siblings responsible for HeII-ionization.

Contribution

It presents the first spatially resolved detection of PopIII-star siblings in IZw18 and emphasizes the significance of aperture effects in WR galaxy studies.

Findings

IFS data of Mrk178 show aperture effects impact WR feature detection

IFS data of IZw18 reveal the full extent of HeII4686 emission

Potential PopIII-star siblings may explain HeII-ionization in IZw18

Abstract

Here we highlight our recent results from the IFS study of Mrk178, the closest metal-poor WR galaxy, and of IZw18, the most metal-poor star-forming galaxy known in the local Universe. The IFS data of Mrk178 show the importance of aperture effects on the search for WR features, and the extent to which physical variations in the ISM properties can be detected. Our IFS data of IZw18 reveal its entire nebular HeII4686-emitting region, and indicate for the first time that peculiar, very hot (nearly) metal-free ionizing stars (called here PopIII-star siblings) might hold the key to the HeII-ionization in IZw18.