- #1
CAF123
Gold Member
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Consider a ##j## point all massive leg one loop polygonal Feynman diagram ##P## representing some scattering process cut on a particular mass channel ##s_i##. Invoking the relevant Feynman rules and proceeding with the integration via dimensional regularisation for example gives me an expression for ##\text{Cut}_{s_i}P\left(p_1^2, \dots, p_j^2, \epsilon\right)##.
I am wondering if someone could explain why it is or is not possible to send the mass corresponding to the channel that was cut to zero if I wanted to consider a massless limit?
Many thanks!
I am wondering if someone could explain why it is or is not possible to send the mass corresponding to the channel that was cut to zero if I wanted to consider a massless limit?
Many thanks!