Identification of 12 High Mass X-Ray Binaries detected by INTEGRAL through NIR photometry and spectroscopy

TL;DR

This study uses optical and near-infrared spectroscopy to identify and classify 15 INTEGRAL-detected high-mass X-ray binaries, revealing their nature as BeHMXBs or sgHMXBs and highlighting the importance of spectral features for classification.

Contribution

It provides new spectroscopic observations that classify 15 INTEGRAL sources, improving understanding of their nature and contributing to the study of high-mass X-ray binary populations.

Findings

6 are Be High-Mass X-ray Binaries

6 are Supergiant High-Mass X-ray Binaries

3 remain unidentified, requiring higher resolution data

Abstract

Since it started observing the sky, the INTEGRAL satellite has revealed new categories of High Mass X-ray binaries in our Galaxy. These observations raise important questions on the formation and evolution of such rare and short-living objects. We present here new observations that enable us to reveal or constrain the nature of 15 new INTEGRAL sources. After previous photometric and spectroscopic campaigns of observations in optical and near infrared, new spectroscopy and photometry were performed at ESO in optical/NIR with EMMI and SOFI on the NTT in 2008 and 2010 on a sample of INTEGRAL sources. These observations and precisely the detection of specific features in their spectra allow the identification of such high-energy objects. Our results indicate that: 6 of these objects are Be High-Mass X-ray Binaries (BeHMXBs), 6 are Supergiant High-Mass X-ray Binaries (sgHMXBs) and 3 are still unidentified and need higher resolution data to be completely unveiled.