PKS 1718−649: a map between solid (1.5–10 keV) and soft (0.3–1.5 keV) lines, including Ch 1, Ch 2, and Ch 3 counts. Blue pixels indicate a hard excess, and red pixels indicate a soft
Scientists conducted an extended X-ray emission in the radio source PKS 1718−649. This is one of the most approximate and comprehensively studied sources of the radio frequency spectrum (GPS). Despite numerous studies, his characterization is still under discussion. Some people believe that we have a compact symmetrical object (CSO) in front of us - a small and powerful extragalactic radio source that exhibits emission on both sides of the active galactic nucleus (AGN). Others think that before us is AGN.
To study the nature of PKS 1718−649, scientists conducted a study of the extended X-ray radiation from the environment of this source. For the review, data from the Chandra X-ray Observatory were used. The analysis showed that the gas releases soft X-rays and acts as part of the expanded hot interstellar medium. In addition, it turned out that the main part of X-rays is produced by diffuse, hot (10 million K) and collision-ionized gas, which dominates nuclear emission.
Researchers are trying to find the most plausible scenario to explain this extended x-ray radiation. There is an assumption that supernovae are the driving mechanism of such radiation. But this excludes the presence of young agn.
The alternative is that supernovae in a host galaxy can feed a galactic halo with a hot x-ray-glowing gas. The new scenario is also confirmed by observations of the active star formation in PKS 1718−649. Therefore, the team claims that supernovae are able to create the observed large-scale X-rays.