For galaxies that have 2 relativistic jets streaming out of its center, what do we know about their composition?
-is it mostly matter or energy or both?
-which sub-atomic particles?
-any other known characteristics (mass, charge, spin, velocity, spectrum, luminosity? etc.)?
If there is not a definitive answer with standard theory, could you please tell me what some of the competing theories are saying about the composition of the matter and or energy seen in relativistic jets?