Momentum measurement

[paweld]

Can anyone give an example of experimient which the momentum of particle is measured in. How to detect eigenstate of momentum if its absolute value is equal 1 in whole space (idealized measurement of momentum should concern all space).

[olgranpappy]

Can anyone give an example of experimient which the momentum of particle is measured in. How to detect eigenstate of momentum if its absolute value is equal 1 in whole space (idealized measurement of momentum should concern all space).

In electron energy loss spectroscopy (EELS) the energy-losses and scattering angles of scattered electrons are measured. The initial energy and direction of the electrons is also known, so that means this is equivalent to measuring the momentum.