Thomson, Modern Particle Physics, Problem 6.7

[blankvin]

In Mark Thomson's Modern Particle Physics, Problem 6.7, I am wondering how we obtain:

2(ms, 0, 0, 0) and -2(ms, 0, 0, 0)

for the RL and LR helicities (likewise for the muon) in the electron currents using helicity combinations. My solutions for the other helicities (RR, LL) work out, but I am not sure how these are obtained for the other helicities (RL, LR). I get (0, 0, 0, 0).

The problem can be viewed here:

https://books.google.ca/books?id=HamyAAAAQBAJ&pg=PA158&lpg=PA158&dq=thomson+modern+particle+physics+6.7&source=bl&ots=u1jyTvgEmV&sig=UAbiPqkke8SYZ_1NmsgPIInjR-c&hl=en&sa=X&ved=0CDwQ6AEwBWoVChMIgYXBtNuxyAIVRB0-Ch17zwD1#v=onepage&q=thomson modern particle physics 6.7&f=false

Thanks,
blankvin.

 

[blankvin]

I was considering the ultra-relatistic regime (E>>m), so abandoned the mass term in my calculation. Using the normalization constant $\sqrt{E+m}$ fixed my problem.Cheers,
blankvin.

 

[Drakkith]

It looks like your link goes to a page that's not available. Could you type the question out or something instead?