Astronomers have made a fascinating discovery about the X-ray binary system Cygnus X-3, located in our Milky Way galaxy about 24,000 light-years away. This system, consisting of a massive star and a likely black hole, emits intense X-rays and has been a subject of study since its discovery in the early 1970s.
Cygnus X-3 is unique in that it exhibits properties similar to some of the most luminous quasars in the universe. Quasars are galaxies with active supermassive black holes at their centers that emit high levels of radiation. The new findings, made possible by NASA’s Imaging X-ray Polarimetry Explorer spacecraft (IXPE), reveal that Cygnus X-3 amplifies its X-ray emission in a funnel-shaped cavity surrounding the probable black hole.
The system’s luminosity is so high that it challenges the Eddington Limit, a property that regulates the flow of matter onto a black hole. Despite this, Cygnus X-3 appears to accrete matter at high rates while maintaining its luminosity. This behavior is reminiscent of ultra-luminous X-ray sources (ULXs) found in quasars.
Recent observations by a team led by Alexandra Veledina of the University of Turku in Finland have shed light on the mechanisms at play in Cygnus X-3. They discovered that the X-rays from the system scatter off the interior of a dense, opaque matter envelope surrounding the compact object. This phenomenon creates a reflection resembling a cup with a mirror interior, amplifying the X-ray emissions.
The degree of polarization in the X-ray light from Cygnus X-3 indicates that the X-rays scatter off the interior of the funnel-shaped cavity, similar to ULXs in quasars. This discovery provides valuable insights into understanding distant ULXs better, as Cygnus X-3 serves as a model for studying these phenomena within our own galaxy.
Further observations are planned to capture the collapse of the funnel-shaped cavity, signaling changes in the structure of the accretion disk. By studying these fluctuations, astronomers hope to gain a deeper understanding of the processes governing Cygnus X-3 and similar systems.
The team’s findings, published in the journal Nature Astronomy, mark a significant step forward in unraveling the mysteries of Cygnus X-3 and its behavior as an X-ray binary system in our galaxy. As researchers continue to investigate this intriguing cosmic phenomenon, our knowledge of black holes, accretion processes, and ultra-luminous X-ray sources stands to expand, opening new avenues for exploration in the field of astronomy.
