Please send me E-mail, dow@ubpheno.physics.buffalo.edu, no later than Monday, January 30, 2006, 2 pm, with your thoughts on:

1. After the discovery of radioactivity by Becquerel in 1896 and Rutherford's discovery of the nucleus in 1911, it was understood that the origin of alpha, beta and gamma rays is the nucleus. While alpha particles and gamma rays emitted in radioactive decays were found to be monoenergetic due to the discrete energy states of the nuclei, the understanding of beta decay turned out to be more complicated: In 1914 James Chadwick measured the energy of beta rays (=electrons) emitted from a radioactive sample of 210 Bi (210 Bi -> 210 Po+e-) and found a continuous spectrum. What possible interpretations can you think of to explain the continous energy spectrum of the electrons emitted in the radioactive decay of 210 Bi ?
(After you thought about it a little bit, you may have a look at the lecture notes.)