An international team of astrophysicists has identified the site where powerful and highly energetic X-rays are being blasted into space from inside a region in space shaped like a giant aquatic mammal called a ‘Manatee’. They found that the spectrum of the object at this location shows that there is a “non-classical acceleration process” where particles are injected and re-accelerated in extremely powerful jets of energy emitted by a black hole. But don’t worry about it irradiating us, since it’s over 100,000,000,000,000 kilometers away. Samar Safi-Harb The astronomical object known as SS 433 has long been known to host a black hole that causes bursts of energy to shoot out into the Galaxy via jets of high-energy particles. Considered the first known microquasar, it is located at the center of what is left of an exploded star in the constellation Aquila, high in the summer night sky. “This fascinating system looks like a beautiful Manatee in space and represents the only known supernova remnant in our Galaxy (out of about 400 such objects) that hosts a black hole,” says UM astrophysicist Dr. Samar Safi-Harb, Tier 1 Canada Research Chair in Extreme Astrophysics and lead author of the paper which includes scientists from Canada, the US, Europe and South Korea. British Mac Intyre UM team member and graduate student Brydyn Mac Intyre helped create a stunning color image of this remarkable astronomical object. The bursts of energy result in two “ear lobes” that glow at radio wavelengths, carved by jets plowing through space at a quarter of the speed of light. “The space along the path of the jet glows brightly in high-energy X-ray and gamma-ray light tens of light-years away from the black hole, but is not visible to the naked eye,” says Mac Intyre. SS 433 is so powerful, astrophysicists have looked for high-energy gamma-ray radiation from the region. In the late 1990s, Safi-Harb proposed that this system accelerates particles to energies higher than what can be achieved in the most powerful particle accelerators on Earth. It took almost 20 years to detect high energy gamma ray radiation. in 2018, researchers at the Cherenkov Water High-Altitude Observatory announced the discovery of high-energy TeV (Tera-electron-volts) gamma rays from the system. However, the location of the particle acceleration could not be detected until now. Kaya Mori Using the European Space Agency’s XMM-Newton satellite and NASA’s NuSTAR satellite, modern X-ray telescopes in orbit, combined with data obtained by NASA’s Chandra X-ray telescope, this team of researchers was able to pinpoint the location of the most “hard” (or higher energy) X-ray emission region near SS 433, believed to be the initiation of large-scale easterly jet emission. Dr Kaya Mori, co-author and astrophysicist at Columbia University in New York, says this powerful energy source, now believed to accelerate particles to very high energies, is a strong candidate for a cosmic ‘PeVatron’, a source that accelerates the cosmic rays upwards. in peta-electron volt energies, or 1,000,000,000,000,000 volts! “Given the unusual nature of the spectrum and the location of the source, this discovery challenges the theory of particle acceleration and shows the injection and reactivation of SS 433 jets at long distances, almost 100 light-years away from the black hole,” he says Safi. -Harb. He adds: “SS 433 teaches us and magnifies the rare case of a supernova remnant powered by a black hole, microquasar, ultraluminous X-ray sources (a growing class of X-ray-emitting sources whose nature is debated) and is a micro- edition of an active galaxy!’ Matthew Band This work involved several students from the University of Manitoba and Columbia University, including Matthew Band, an undergraduate summer research awardee from UM’s Price Faculty of Engineering, who is a co-author on the paper. “I didn’t expect my summer job to be anything but this, I’m excited,” he said. “It is an honor to learn from such great people and to be a part of this international collaboration.” The researchers announced the discovery in a paper published in the Astrophysical Journal, which will be presented soon at the International Symposium on High-Energy Gamma-ray Astronomy in Barcelona. UM Today Staff
