An article published in the journal “Monthly Notices of the Royal Astronomical Society” is the first produced thanks to a study that includes observations of the Sardinia Radio Telescope (SRT). Its target was a supermassive black hole at the center of an elliptical galaxy about 300 million light years away from Earth that is falling toward the galaxy cluster 3C 129.
The SRT is located north of Cagliari and has an antenna 64 meters in diameter. Its construction was funded by the Ministry of Instruction, of University, and Research (MIUR), Italian Space Agency (ASI), and the Autonomous Region of Sardinia (RAS) and is operated by the National Institute of Astrophysics (INAF). This radio telescope was officially opened in 2013 and after the astronomical validation stage the real scientific work started.
The SRT has a sensitivity in the radio frequencies between 0.3 and 116 GHz thanks to an innovative active surface composed of 1,008 panels digitally controlled by actuators. This allows to compensate for the gravitational deformation of the structure and change the shape of the antenna depending on the focal position used. Only very few radio telescopes have such an advanced system and the consequence is that the SRT allows for high quality observations.
In this study, the SRT allowed to observe the polarized light coming from the target. The polarization provides a lot of information such as the strength and orientation of magnetic fields. Near the supermassive black hole, the plasma flow is chaotic but along the wake it’s more regular and the polarization increases gradually. That reveals the presence of highly ordered magnetic fields. The quality of this type of observation shows that the SRT is already at excellent setup levels.
The observations of the supermassive black hole revealed that it’s absorbing matter from the disk surrounding it. Howerver, part of this matter is ejected in two plasma jets which form a radio wake much longer than the whole galaxy hosting this black hole. The comparison with observations from other telescopes shows that it’s moving at about 6 million km/h.
In front of the galaxy that hosts this supermassive black hole a shock wave was found. It’s similar to the one that precedes an aircraft traveling at supersonic speed. The measured speed corresponds to that theorized in the past to explain the existence of this shock wave.
The SRT was used in combination with the SARDARA (Sardinia Roach2-based Digital Architecture for Radio Astronomy) backend, funded by the Autonomous Region of Sardinia. It was recently installed at the telescope and the results show that these instruments will make a significant contribution to astronomical research.
