Chinese astronomers have used the Hard X-ray Modulation Telescope (HXMT) to observe the latest outburst of a low-mass X-ray binary system known as GX 339-4. They detected new quasi-periodic oscillations in this source. Their findings have been published on the pre-print server arXiv.
X-ray binaries (XRBs) consist of a normal star or a white dwarf transferring mass onto a compact neutron star or a black hole. Based on the mass of the companion star, astronomers divide them into low-mass X-ray binaries (LMXB) and high-mass X-ray binaries (HMXB).
Located some 39,000 light years away from the Earth, GX 339-4 is a recurrent black hole LMXB first detected in 1973. Its black hole is estimated to be at least 5.8 times as massive as the sun. GX 339−4 has undergone frequent outbursts, experienced quasi-periodic oscillations (QPOs) and displayed all the black hole accretion states during the last thirty years.
All in all, GX 339-4 has been comprehensively investigated at all wavelengths, making it one of the most studied black hole LMXBs.
The latest outburst of GX 339-4 began in early 2021 and a team of astronomers led by Wei Wang of the Wuhan University in China, decided to perform HXMT observations of this event in order to shed more light on the behavior of this system. This resulted in the detection of new quasi-periodic oscillations (QPOs).
2023-07-05 03:00:06
Original from phys.org rnrn