Collapsing the wavefuntion to an Energy Eigenfunction?

[mkarydas]

Is there an experiment that can measure the energy of a single particle so immediately after it has collapsed to one of the energy eigenfunctions?
The problem is that all experiments i can think of are about measuring the position of a the particle so we collapse it to its delta function. But how can someone experimentally measure the energy of a particle ?

 

[bhobba]

What's your question?

How someone measures experimentally the energy of a particle? - well its done all the time in particle colliders.

How one measures it immediately after - simply do the same experiment immediately after - of course if the measurement didn't destroy it.

Thanks
Bill

 

[mkarydas]

thats exactly my question..how does one measure the energy of a particle without measuring its position first?

 

[bhobba]

thats exactly my question..how does one measure the energy of a particle without measuring its position first?

Mass spectrometer is one way - probably others as well.

Thanks
Bill