C IV Emission-line Detection of the Supernova Remnant RCW 114

TL;DR

This study detects C IV emission in RCW 114, revealing it is a nearby supernova remnant unrelated to WR 90, and shows its complex evolution in a non-uniform interstellar medium.

Contribution

It provides the first detection of C IV emission in RCW 114, clarifying its distance and disassociating it from WR 90, and reveals its complex interaction with the surrounding medium.

Findings

RCW 114 is closer than WR 90.

RCW 114 is an old supernova remnant.

RCW 114 evolved in a non-uniform interstellar medium.

Abstract

We report the detection of the C IV 1548, 1551 emission line in the region of the RCW 114 nebula using the FIMS/SPEAR data. The observed C IV line intensity indicates that RCW 114 is much closer to us than WR 90, a Wolf-Rayet star that was thought to be associated with RCW 114 in some of the previous studies. We also found the existence of a small H I bubble centered on WR 90, with a different local standard of rest velocity range from that of the large H I bubble which was identified previously as related to RCW 114. These findings imply that the RCW 114 nebula is an old supernova remnant which is not associated with WR 90. Additionally, the global morphologies of the C IV, H-alpha, and H I emissions show that RCW 114 has evolved in a non-uniform interstellar medium.