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Auger update on (an)isotropy of ultra high energy cosmic rays; More power coming in jets than in accretion disks (Nature)

Prof. Edivaldo Santos gave us a very nice overview of the recent paper published by the Auger Collaboration on the anisotropy of ultra high energy cosmic rays. Puzzling enough, the signal got even more isotropic than before. He discussed in detail the various statistical measures of anisotropy and the different astronomical catalogs against which the cosmic ray data was compared to. Why is the signal almost isotropic is a question we did not discuss. Are the intergalactic magnetic fields much stronger than  we thought?

Searches for Anisotropies in the Arrival Directions of the Highest Energy Cosmic Rays Detected by the Pierre Auger Observatory http://adsabs.harvard.edu/abs/2014arXiv1411.6111P


Following Prof. Santos, Chandra Singh told us about the main result in the Nature paper below. It was not clear to us how model-dependent the jet power estimates are and the size of the uncertainties was also interesting.

The power of relativistic jets is larger than the luminosity of their accretion disks, Nature 

http://www.nature.com/nature/journal/v515/n7527/full/nature13856.html
http://arstechnica.com/science/2014/11/black-hole-jets-how-do-they-work-magnets/
http://news.sciencemag.org/physics/2014/11/what-powers-black-holes-mighty-jets

Chandra prepared some slides about this paper: AGN_meeting_Dec05 2014 Chandra

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