Scientific Colloquium
Thursday, February 24, 2011, 3:30 p.m
NOTE SPECIAL DAY
THE JOHN BAHCALL LECTURE |
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ROGER
BLANDFORD
STANFORD UNIVERSITY
KAVLI INSTITUTE OF PARTICLE ASTROPHYSICS AND COSMOLOGY
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"Higher Energy Astrophysics"
Astronomical observations
have demonstrated that cosmic sources are capable of accelerating
protons and electrons to unexpectedly large energies with surprisingly
high efficiency. Supernova remnants accelerate protons and electrons to
nearly a thousand times the energy produced by terrestrial particle
accelerators and unspecified, but cosmologically local sources achieve
proton energies nearly a million times greater. Recent observations by
the Auger, Chandra, Fermi, H.E.S.S., MAGIC and VERITAS telescopes will
be briefly summarized and it will be argued that novel particle
acceleration mechanisms are at work. Although there is no compelling
evidence that new fundamental physics processes are needed, the
observations do illustrate some remarkable features of higher energy
physics.