An international workforce of astronomers has detected a new high-mass gamma-ray binary (HMGB) within the Milky way galaxy. The newly discovered HMGB, designated 4FGL J1405.1-6119, is one in all solely a handful of such objects found so far. The discovery was declared in a paper published August 28 on the arXiv pre-print repository.
HMGBs include an OB star in orbit with a compact object. In these methods, interactions between the two objects result in emission with spectral energy distribution (SED) peaks above 1.0 MeV. They’re assumed to be precursors to high-mass X-ray binaries (HMXBs).
HMGBs are scarce objects. Astronomers estimate that there are about 100 nonetheless undetected HMGBs residing in our home galaxy. Moreover, many known gamma-ray sources of as-yet-unknown nature may probably be high-mass gamma-ray binaries.
Led by Robin Corbet, a group of astronomers at the University of Maryland has just lately carried out a seek for gamma-ray binaries. They’ve analyzed the information collected by the Large Area Telescope (LAT) onboard NASA’s Fermi gamma-ray space telescope, aiming to find indicators of periodic modulation in gamma-ray light curves of different sources. The study, complemented by information from NASA’s Swift spacecraft and Australia Telescope Compact Array (ATCA), allowed the researchers to find out that one particular source identified by LAT is an HMGB.
According to the study, the outcomes point out that the modulation period is the orbital interval of 4FGL J1405.1-6119. The first star of the system, situated some 25,000 light-years away, was discovered to be an O-type star (most probably of spectral sort O6.5 III) with a mass between 25 and 35 solar masses. Subsequently, the researchers categorized the binary as a brand new HMGB.