Study of the luminous blue variable star candidate G26.47+0.02 and its environment

TL;DR

This study investigates the LBV star candidate G26.47+0.02 using multiwavelength data, revealing a surrounding molecular shell, potential binary nature, and interaction with the interstellar medium, advancing understanding of massive star evolution.

Contribution

It provides the first multiwavelength analysis of G26.47+0.02, suggesting its binary nature and interaction with the environment, which was not previously established.

Findings

Molecular shell partially surrounds the nebula, indicating stellar wind interaction.

G26.47+0.02 is located at approximately 4.8 kpc distance.

Evidence of both thermal and non-thermal emission suggests wind-wind collision shocks.

Abstract

The luminous blue variable (LBV) stars are peculiar very massive stars. The study of these stellar objects and their surroundings is important for understanding the evolution of massive stars and its effects on the interstellar medium. We study the LBV star candidate G26.47+0.02. Using several large-scale surveys in different frequencies we performed a multiwavelength study of G26.47+0.02 and its surroundings. We found a molecular shell (seen in the 13CO J=1-0 line) that partially surrounds the mid-infrared nebula of G26.47+0.02, which suggests an interaction between the strong stellar winds and the molecular gas. From the HI absorption and the molecular gas study we conclude that G26.47+0.02 is located at a distance of ~4.8 kpc. The radio continuum analysis shows a both thermal and non-thermal emission toward this LBV candidate, pointing to wind-wind collision shocks from a binary system. This hypothesis is supported by a search of near-IR sources and the Chandra X-ray analysis. Additional multiwavelength and long-term observations are needed to detect some possible variable behavior, and if that is found, to confirm the binary nature of the system.