AstroSat to Unveil Modulation in Black Hole Binary Source

  • 21 May 2024

In May, 2024, Indian astrophysicists leveraged observations from AstroSat to uncover aperiodic modulation in Swift J1727.8-1613, a black hole binary source, offering insights into black hole dynamics.

Key Points

  • BH-XRB System: Black hole X-ray binary systems consist of a black hole and a companion star, revealing insights into accretion processes.
  • QPO Frequency Variation: Quasi-Periodic Oscillation frequency of high-energy photons in BH-XRB Swift J1727.8-1613 increased from 1.4 Hz to 2.6 Hz over seven days during an outburst phase.
  • Significance of QPOs: Quasi-Periodic Oscillations shed light on black hole gravitational strength and fundamental properties, aiding in understanding accretion dynamics.
  • Publication in Scientific Journal: The discovery was reported in the Monthly Notices of the Royal Astronomical Society by astrophysicists from various Indian research institutions.
  • Observational Methods: Utilizing AstroSat's Large Area X-ray Proportional Counter, astrophysicists examined QPO variability at higher energies and used data from the Neutron Star Interior Composition Explorer onboard the International Space Station.
  • Discovery Background: Swift J1727.8-1613, discovered by NASA's Swift Burst Alert Telescope, was observed by AstroSat for the first time in September 2024.
  • Collaborative Effort: The research involved contributions from U R Rao Satellite Centre/ISRO, Indian Institute of Technology Guwahati, University of Mumbai, and Tata Institute of Fundamental Research.