Gamma Rays Part 2 - Blazars
Gamma rays can be generated by several sources here on Earth. Those are described in part 1 (background for this part). Blazars are a distant source. There are 2 parts in this series rather than one very long post. quotes from NASA: ' A blazar is an active galactic nucleus (AGN) with a relativistic jet (a jet composed of ionized matter traveling at nearly the speed of light) directed very nearly towards Earth. Relativistic beaming of electromagnetic radiation from the jet makes blazars appear much brighter than they would be if the jet were pointed in a direction away from the Earth. Blazars are powerful sources of emission across the electromagnetic spectrum and are observed to be sources of high-energy gamma rays. Blazars are highly variable sources, often undergoing rapid and dramatic fluctuations in brightness on short timescales (hours to days). Some blazar jets exhibit apparent superluminal motion, another consequence of material in the jet traveling toward the observer at nearly the speed of light.
The blazar category includes BL Lac objects and optically violently variable (OVV) quasars. The generally accepted picture is that BL Lac objects are intrinsically low-power radio galaxies while OVV quasars are intrinsically powerful radio-loud quasars. The name "blazar" was coined to denote the combination of these two classes.
In visible-wavelength images, most blazars appear compact and pointlike, but high-resolution images reveal that they are located at the centers of elliptical galaxies. '
I am immediately suspicious of a jet that must be aligned toward Earth to be seen. This is the explanation offered for the jet's brightness. That implies there are more jets but just not in our alignment. I have posted twice about elliptical galaxies. A core with a proposed black hole is more likely to be a torus generating synchrotron radiation, like in M87.
' Gamma rays emitted by M87 have been observed since the late 1990s.'
Wal Thornhill offered an excellent explanation for the plasmoid at the core of the elliptical galaxy M87 as well as its jets. This video, via the Space News channel, can be found in Youtube with a search for 'thornhill plasmoid'; the video was released April 8, 2019.
The generation of the jets starts at around 10 minutes of the 15 minute video. I suspect those 5 most energetic blazars detected by the Fermi Telescope are actually galaxies like M87 but with much more electrical energy in its plasmoid configuration than the hundreds of other known blazars.
From a University of Wisconsin document on blazars: ' Blazars are among the most luminous objects in the sky," "This is because we are seeing them in a very special orientation." A signature geometric feature of AGNs, including blazars, are twin relativistic jets that shoot from the poles of the rapidly spinning black hole.
Powerful magnetic fields are wound up on the spin axis of the black hole, and particles – photons, protons, neutrinos – are accelerated through the jet and sent coursing through the cosmos. ' I notice a coincidence of pairs in the universe. Arp observed quasars of a similar red shift could be a pair around a Seyfert. However Seyferts are spirals and M87 is an elliptical. Both can have an X-ray source in their core. I suspect their plasmoids are similar for their material ejection along the rotation axis.
Blazars are being considered a source for cosmic rays.
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