Energy Dependence of Scattering Phase Shifts

[FunkyDwarf]

Hey all,

This might seem like a strange/silly question but just humour me if you could...

Is there any a-priori reason why a scattering phase shift should be linear in energy (energy of the incoming particle at infinity)? Are there examples of such shifts that have a different energy dependence ?

Cheers!

EDIT: Also FYI I am working in a relativistic framework so using relativistic energy/momentum relations.

 

[Bill_K]

I don't think this is ever the case.