The researchers conducted multi-wavelength photometric and spectropolarimetric observations of the quasar 3C 279, in which they noticed three different periods of activity.
3C 279 is located on the territory of Virgo and represents an optically violent alternating quasar (quasi-star radio source), known for its variations in visible, radio and X-ray bands. Recent surveys have shown that 3C 279 should be attributed to the group of blazars, a very compact quasar associated with a supermassive black hole in the center of an active large-scale elliptical galaxy.
Blazars can be perceived as high-energy engines, serving as natural laboratories for studying particle acceleration, relativistic plasma processes, magnetic field dynamics, and black hole physics. Despite the large number of observations in 3C 279 at different wavelengths, there are still uncertainties regarding the location of the creation of gamma rays at the source. To understand, scientists from the Institute of Radio Astronomy. Max Planck (Germany) analyzed light curves for 3C 279 from 1 mm to gamma rays over a period of 6 years.
Polarimetric observations behavior compared to gamma rays and UV continuum for 3C 279
The analysis revealed three different periods of activity in 3C 279 (A, B and C). During period A, multiple flashes were observed in gamma radiation, as well as analogs in the optical (V-range), UV-continuum and near-IR radiation. During period B, multiple flashes were identified in the optical V-range with clear analogs in the UV-spectral continuum and near-IR.
At time C, we managed to observe the highest levels of gamma rays. Everything points to the fact that the dominant mechanism for creating gamma rays in 3C 279 changes with time. But there is a possibility that the location of the gamma-radiation zone itself may change, based on the state of activity of the central engine.