What do you know about Relativistic Lifetimes?

       
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Brainstorm

 In a small group write down everythingyou know about the applications of energy and momentum in HEP on butcher paper. At the same time write down questions or ideas that you are not sure about on another sheet of paper. After you have 10-20 good items, or just feel it is time to stop, go back and discuss each one. Look for connections between the items. Reorganize them into a diagram . . . this will serve as your first-order conceptual framework for discussing the energy-momentum relationship.

These questions build a foundation for investigating this topic:

  1. What do we mean by the "lifetime" of a particle? Is it the time for one particle to decay into daughter particles?

  2. A particular type of particle has lifetime T. If a sample of these particles is created together in a lab at time t = 0, will they all decay at t = T? If not, how many will still exist as the original particle at t = T?

  3. Do muons observed "at rest" in the lab have the same apparent lifetimes as muons observed to be moving at near the speed of light?

  4. Do you know the basic equations of relativity? Write down what you think you know and then check against the Equations Page.

  5. Find out how well do you understand special relativity. Assess Your STR Knowledge.

  6. A particular particle has a lifetime of 5 microseconds in its own reference from. Its speed is 0.95 c. What does its lifetime appear to be in the reference from of an observer "at rest"?