Preflight 2

Post your response on the course Compass site

Due Friday, Sept. 18, 12noon

Suggested Readings:

Particle Physics

For particle physics neophytes (and even more seasoned veterans) I recommend the online tutorial The Particle Adventure. It's an easy read, yet covers a lot of the main issues and terminology that you need to know. Elsewhere, a nice history of neutrinos is available, as is a discussion of big bang science.

Unfortunately, while these descriptive discussions are very good, there are few brief introductions to particle physics that are written at a higher level, i.e., assuming a graduate knowledge of physics but not a prior knowledge of particle physics. If you are aware of such a review, please let me know! For now, the best I can do is to recommend the the introductory but not-so-brief text:
Perkins, Introduction to High-Energy Physics (probably on reserve for Physics 470).

Cosmology

The Boyd text has a nice and very accessible introduction to cosmology.

A good online introduction is this cosmology tutorial.

Questions

The questions are really meant to help guide your thinking as you read. You may find it helpful to look at the questions first and bear them in mind as you read.

  1. Nuclear Structure Redux.
    Free neutrons which are not bound in nuclei are unstable against beta-day. On the other hand, neutrons in stable nuclei do not decay.

    What explains this difference?

  2. Nuclear Reactions and Decays.
    In exoergic (exothermic) nuclear reactions, where does the released binding energy Q go--i.e., in the final state, what form does it take?

    Why do beta-decays lead to a spectrum of electron energies? What are the maximum and minimum energy values?

    What conservation law(s) (if any) prevents the spontaneous decay of a dueteron to a proton and neutron?

  3. Particle Physics.
    What is parity? What is meant by the conservation of parity? How does this compare to, say, conservation of energy (similarities, differences)? Which of the fundamental interactions conserve parity? Which violate parity?

    Protons and electrons are observed to be stable, i.e., no spontaneous proton or electron decay has ever been observed. What conservation law(s) prevent protons from decaying (into, e.g., photons)? What conservation law(s) prevent electrons from decaying (into, e.g., photons)?
    What conservation laws (if any) apply to the decays of charged pions?

    What are the main similarities and differences among the three generations of fundamental particles? What is special about the first generation?

  4. Cosmology.
    What are the three sets of observations that provide the strongest evidence for the hot big bang cosmology? What cosmic epochs are probed by each of these three "pillars" of cosmology, i.e., what is a rough timescale or energy/temperature scale associated with each pillar?

    How does the expansion of the Universe depend on the particle content of the universe?

  5. What material did you find difficult, confusing, or unclear? What material would you like to know more about?

  6. Other questions or comments?