The most energetic (ultra-high-energy) cosmic rays are probably created with energies up to 1ZeV = 10 21
Question:
The most energetic (ultra-high-energy) cosmic rays are probably created with energies up to ∼1ZeV = 1021 eV in sources roughly 100 million light-years away.
(a) Show that they start with the “energy of a well-hit baseball and the momentum of a snail.” By the time they arrive at Earth, their energies are likely to have been reduced by a factor of ∼3.
(b) Assuming that the intergalactic magnetic field is ∼10−13 T ∼10−9 G, compute the cosmic rays’ Larmor radii, assuming that they are protons and iron nuclei.
(c) Do you expect their arrival directions to point back to their sources?
(d) Suppose that an ultra-high-energy cosmic ray collides with a stationary nitrogen nucleus in our atmosphere. How much energy becomes available in the center-of mass frame? Compare this with the energy at the Large Hadron Collider, where protons, each with energy ∼7 TeV, collide head on.
Step by Step Answer:
Answer a To show that ultrahighenergy cosmic rays start with the energy of a wellhit baseball and the momentum of a snail we need to compare their initial energy and momentum with those of a baseball ...View the full answer
Modern Classical Physics Optics Fluids Plasmas Elasticity Relativity And Statistical Physics
ISBN: 9780691159027
1st Edition
Authors: Kip S. Thorne, Roger D. Blandford
