Relativistic jet

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Relativistic jet. The environment around the AGN where the relativistic plasma is collimated into jets which escape along the pole of the supermassive black hole
Elliptical galaxy M87 emitting a relativistic jet, as seen by the Hubble Space Telescope

Relativistic jets are very powerful jets of plasma with speeds close to the speed of light.[1] They are emitted by the central black holes of some active galaxies (notably radio galaxies and quasars), and by the black holes of massive stars and neutron stars. Their lengths can reach several thousand or even hundreds of thousands of light years.[2][3]

If the jet speed is close to the speed of light, the effects of the special theory of relativity are significant. The mechanics behind how jets are created,[4][5] and what they are made of, are still a matter of debate.[6] Jet composition might vary.[7][8]

Massive galactic central black holes have the most powerful jets. Similar jets on a much smaller scale develop from neutron stars and black holes in other stars. Even weaker and less relativistic jets may be associated with many binary star systems.

The general hypothesis among astrophysicists is that the formation of relativistic jets is the key to explaining the production of gamma-ray bursts. These jets have Lorentz factors of ~100 or greater (that is, speeds over roughly 0.99995c), making them some of the fastest celestial objects known at present.

References[change | change source]

  1. Wehrle A.E; Zacharias N. & Johnston K. 2009. "What is the structure of relativistic jets in AGN on scales of light days?". Astro2010: the Astronomy and Astrophysics Decadal Survey 2010: 310. 
  2. Biretta J. 1999. "Hubble detects faster-than-light motion in Galaxy M87". 
  3. "Evidence for ultra-energetic particles in jet from black hole". Yale University – Office of Public Affairs 2006. Archived from the original on 2008. 
  4. Meier, David L 2003. "The theory and simulation of relativistic jet formation: towards a unified model for micro- and macroquasars". New Astronomy Reviews 47 (6–7): 667. doi:10.1016/S1387-6473(03)00120-9. 
  5. Semenov V. et al 2004. "Simulations of jets driven by black hole rotation". Science 305 (5686): 978–980. doi:10.1126/science.1100638. PMID 15310894. 
  6. Georganopoulos, Markos et al 2005. "Bulk comptonization of the cosmic microwave background by extragalactic jets as a probe of their matter content". The Astrophysical Journal 625 (2): 656. doi:10.1086/429558. 
  7. Wardle J.F.C. 1998. "Electron–positron jets associated with the quasar 3C279". Nature 395: 457–461. doi:10.1038/26675. 
  8. "NASA – Vast cloud of antimatter traced to binary stars".