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View Full Version : Is a Nearby Object in Space Beaming Cosmic Rays at Earth?



Fraser
2009-May-04, 06:20 PM
Data from several different space and ground based observatories imply the presence of a nearby object that is beaming cosmic rays our way. Scientists with the Fermi Space Telescope say an unknown pulsar may be close by, sending electrons and positrons towards Earth. Or another more exotic explanation is that the particles could come [...]

More... (http://www.universetoday.com/2009/05/04/is-a-nearby-object-in-space-beaming-cosmic-rays-at-earth/)

Francois Plouin
2009-Jul-03, 07:16 AM
Recently the Auger experiment claimed to have found that the highest energy CR are coming from remote objects, say (?) 200 Mpc. However this hypothesis seems not to be fully confirmed. The finding of new close energetic objects opens up different perpectives, more in accord with large scale Universe uniformity. Thus, every class of galactic object is interesting to be considered. The most popular ones are supernovae associated to shock acceleration. However the existence of an energy cut-off at about 10^15 eV opened for a variety of speculations since the cosmic rays spectrum continuously well above this cut-off. In this context, the fact that the cosmic ray energy spectrum has the simple form of a power law in energy, typically E^2.7, makes these speculations of new source species for each new energy domain opened fot observation seemingly be based on a miraculous conspiration for uniformity up to the largest energies, i.e. Auger experiment. This, in some way, reminds to the ptolemaic astronomy.

It would be interesting to examine, in the present case, the particle production by dark matter, neutron stars, etc...