Midterm Exam (129A), Oct 31
1. Explain (1) why color degrees of freedom was introduced, using one
baryon wave function of your choice as an example, and (2) what is
the most convincing evidence for the color degrees of freedom we have
now. (At most half a page each. 10 points each.)
2. Estimate the decay rate Λ0→pe−¯νe, and compare to the data. (20
points.)
3. Do the following processes occur? If yes, draw the Feynman diagram
for the process. If not, quote the reason. (3+3 points each)
(a) µ−
→e−νe¯νe
(b) pn →Λ0K+n
(c) e+e−
→b¯
b
(d) ω0→π0π0
(e) K+→π0µ+νµ
(f) Σ0→K−p
(g) p→µ+π0
(h) ¯νep→e+n
(i) ∆++ →pπ+
(j) e+e−
→µ+νµ