# Limit of Scattering Angle Theta in Lab Frame

The quantity is known as the

# In the CM Frame

where and is the angle between the before and after momentum in the CM frame

Using the relativistic relation this reduces to

For , by symmetry this implies

This can be rewritten again using the relativistic energy relation

with

and

# Maximum Moller Scattering Angle Theta in Lab Frame

Since u is invariant between frames

with for

As found earlier, the Moller electron has a maximum energy possible of:

Using the relativistic energy relation,

for