20-year-old mystery of mysterious cosmic radiation revealed
An international team of scientists has identified the type of mysterious space object that is the source of the mysterious gamma radiation using distributed computing. The research findings, which reveal a 20-year astrophysical mystery, are published in The Astrophysical Journal.
The unknown source of gamma rays PSR J1653-0158 was first observed in 1999. In 2009, scientists began to speculate that it might be a neutron star, and since 2014 it has become clear that the source is a dense binary system. The new study involved 10,000 volunteers who donated the computing power of the GPUs of personal computers and other devices that are idle to the Einstein @ Home project. The goal was to detect weak gamma-ray pulsations when analyzing data from the Fermi Space Telescope.
Pulsations are a characteristic feature of a neutron star that spins and emits directional radiation – in this case, it is called a gamma or radio pulsar. If a neutron star is part of a binary system, that is, it has a companion, then it pulls its substance onto itself, forming a plasma cloud impenetrable for radio emission. Scientists call these neutron stars “black widows.” The pulsar turns out to be invisible in radio beams and can only be detected by subtle oscillations in gamma radiation.
It turned out that PSR J1653-0158 is indeed a pulsar that rotates around its axis at a speed of 30 thousand revolutions per minute, which makes it one of the fastest objects of its type. Its magnetic field is unusually weak for neutron stars, and its mass is slightly more than two solar masses. The mass of its satellite reaches about one percent of the mass of the Sun. The couple turns around each other every 75 minutes.