Momentum of photons in CM frame.

vela

Try aligning the x-axis to point along ##\vec{p}_1 + \vec{p}_2##. You'll have to find the angle each photon makes with the axis, but that should be straightforward.

vela Recognitions: Gold Member Homework Help Science Advisor Staff Emeritus	Try aligning the x-axis to point along ##\vec{p}_1 + \vec{p}_2##. You'll have to find the angle each photon makes with the axis, but that should be straightforward.