HW10 - PHY5667 Problem Set#10(due Tue Nov 2(1 Consider a...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
PHY5667 Problem Set #10 (due Tue Nov 2) (1) Consider a theory of a neutral scalar φ (mass m φ ) and a Dirac fermion ψ (mass m ψ ) with the interaction L int = - λφ ψψ , where λ is a real constant. Assume m φ > 2 m ψ . (i) Obtain the Feynman rule for the φ - ψ a - ψ b vertex, where a, b = 1 , · · · , 4 label Dirac- spinor components. Indicate charge and momentum arrows wherever necessary. (ii) Compute the amplitude M fi for the decay process φ ψ + ψ , where the initial φ is at rest and the final ψ and ψ have 4-momenta ( E, ~ k ) and ( E 0 , ~ k 0 ) and spins s and s 0 , respectively. (iii) Compute the “total” decay rate (i.e. the final spins s and s 0 being summed over) for φ ψ + ψ . (2) Consider a theory of a charged vector A μ (mass m A ) and two Dirac fermions ψ 1 and ψ 2 (mass m 1 and m 2 , respectively) with the interaction L int = - gA μ ψ 1 γ μ ψ 2 - g * A μ ψ 2 γ μ ψ 1 , where g is a complex constant. Assume m 1 > m A + m 2 . (i) Obtain the Feynman rules for the A μ -( ψ 1 ) a -( ψ 2 ) b and A μ -( ψ 2 ) a -( ψ 1 ) b vertices, where a, b = 1 ,
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern