Walter L. Wagner
12-29-07, 05:57 PM
The following is abstracted from Symmetry, Volume 04, issue 08/09, oct/nov 07 [a joint Fermilab/SLAC publication], from an article entitled "On the trail of COSMIC BULLETS" by Kurt Riesselmann. See also Science, November 9, 2007:
Though not yet completed, the Pierre Auger observatory particle detectors [1500 water tanks of some 3,000 gallons each, lined with photo sensors, spread over some 1200 square miles of Argentine pampas] have recorded about 1,000,000 cosmic rays since January, 2004 when operations commenced. This included about 100 ultrahigh energy cosmic bullets. These are so rare that only one or two might hit each square mile per century.
"In early November, 2007, the Pierre Auger team announced the first results of its efforts to track cosmic bullets back to their sources. They looked at the 27 most energetic cosmic rays, those with energies of more than 57 billion billion electronvolts.
Rather than coming from points scattered across the sky, the tracks of most of these rays led straight back to nearby regions of space that are home to active galactic nuclei -- supermassive black holes at the centers of some galaxies, such as Centaurus A. ...
Active galactic nuclei are a million to billions of times as massive as our sun. ...
As they devour huge amounts of gas, dust, and other matter, they create and eject prodigious amounts of energy and particles. If, as the Auger findings suggest, they are responsible for firing cosmic bullets, they are the most powerful accelerators in the universe ... "
To track the path of the cosmic ray, the observatory has both the detector tanks to record the shower that strikes earth, as well as 24 fluorescence telescopes, housed in 4 buildings, that scan the overhead sky, looking for the faint glow created when billions of particles from a cosmic ray shower interact with nitrogen molecules in the atmosphere. By plotting both the impact 'point' of the shower, as well as the fluorescence path, a fairly accurate portrait to within about 0.1 degrees of the path of the cosmic ray particle is created.
The very highest energy ones are only slightly deflected by magnetic fields during their several hundred million year transit [at about 0.9999+ c] from point of origin to earth, such that they still point back to within a degree or two from their place of origin in the active galactic nuclei.
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This is an impressive result, which I anticipate might well become the proven case upon obtaining additional data over a few more years of observation.
Some may have noted that in other posts I speculated that the highest-E cosmic rays might actually be the break-up of exotic particles. This result suggests to the contrary [but does not eliminate that as a possible contribution]; namely that the highest-E cosmic rays are actually high-speed protons, accelerated by magnetic fields associated with active galactic nuclei [black holes]. This eliminates one of the concerns associated with the LHC at CERN, but not the main concern that the LHC [Large Hadron Collider] might create "at rest" miniature black holes [MBHs], whereas the high-speed protons striking earth ejected from these active galactic nuclei would create such MBH at relativistic speed, with their potential to safely zip through earth with hardly an interaction [neutrino-like].
Perhaps it might be possible to install gamma ray detectors at Pierre Auger to search for the possible signal of an "evaporating" MBH, which is what some proponents of the LHC have suggested is the likely outcome of the production of a MBH at rest relative to earth, which is why they argue production of a MBH should be safe, due to their predicted rapid "evaporation".
Though not yet completed, the Pierre Auger observatory particle detectors [1500 water tanks of some 3,000 gallons each, lined with photo sensors, spread over some 1200 square miles of Argentine pampas] have recorded about 1,000,000 cosmic rays since January, 2004 when operations commenced. This included about 100 ultrahigh energy cosmic bullets. These are so rare that only one or two might hit each square mile per century.
"In early November, 2007, the Pierre Auger team announced the first results of its efforts to track cosmic bullets back to their sources. They looked at the 27 most energetic cosmic rays, those with energies of more than 57 billion billion electronvolts.
Rather than coming from points scattered across the sky, the tracks of most of these rays led straight back to nearby regions of space that are home to active galactic nuclei -- supermassive black holes at the centers of some galaxies, such as Centaurus A. ...
Active galactic nuclei are a million to billions of times as massive as our sun. ...
As they devour huge amounts of gas, dust, and other matter, they create and eject prodigious amounts of energy and particles. If, as the Auger findings suggest, they are responsible for firing cosmic bullets, they are the most powerful accelerators in the universe ... "
To track the path of the cosmic ray, the observatory has both the detector tanks to record the shower that strikes earth, as well as 24 fluorescence telescopes, housed in 4 buildings, that scan the overhead sky, looking for the faint glow created when billions of particles from a cosmic ray shower interact with nitrogen molecules in the atmosphere. By plotting both the impact 'point' of the shower, as well as the fluorescence path, a fairly accurate portrait to within about 0.1 degrees of the path of the cosmic ray particle is created.
The very highest energy ones are only slightly deflected by magnetic fields during their several hundred million year transit [at about 0.9999+ c] from point of origin to earth, such that they still point back to within a degree or two from their place of origin in the active galactic nuclei.
----
This is an impressive result, which I anticipate might well become the proven case upon obtaining additional data over a few more years of observation.
Some may have noted that in other posts I speculated that the highest-E cosmic rays might actually be the break-up of exotic particles. This result suggests to the contrary [but does not eliminate that as a possible contribution]; namely that the highest-E cosmic rays are actually high-speed protons, accelerated by magnetic fields associated with active galactic nuclei [black holes]. This eliminates one of the concerns associated with the LHC at CERN, but not the main concern that the LHC [Large Hadron Collider] might create "at rest" miniature black holes [MBHs], whereas the high-speed protons striking earth ejected from these active galactic nuclei would create such MBH at relativistic speed, with their potential to safely zip through earth with hardly an interaction [neutrino-like].
Perhaps it might be possible to install gamma ray detectors at Pierre Auger to search for the possible signal of an "evaporating" MBH, which is what some proponents of the LHC have suggested is the likely outcome of the production of a MBH at rest relative to earth, which is why they argue production of a MBH should be safe, due to their predicted rapid "evaporation".