Normalization Constant for Gaussian

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atomicpedals
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Homework Statement



Find the normalization constant N for the Gaussian wave packet
[tex]\psi (x) = N e^{-(x-x_{0})^{2}/2 K^{2}}[/tex]

Homework Equations


[tex]1 = \int |\psi (x)|^{2} dx[/tex]

The Attempt at a Solution


[tex]1 = \int |\psi (x)|^{2} dx = N^{2} \int e^{-(x-x_{0})^{2}/K^{2}} dx[/tex]
Substitute [itex]y=(x-x_{0})[/itex]
[tex]N^{2} \int e^{-y^{2}/K^{2}} dy[/tex]
Substitute again [itex]z = y/|K|[/itex]
[tex]N^{2} \int e^{-z^{2}} dz = N^{2} x_{0} K \sqrt{\pi}[/tex]
[tex]N= ( \frac{1}{K x_{0} \sqrt{\pi}})^{1/2}[/tex]
Where my question lies is with the [itex]x_{0}[/itex] in N. Should that be there?
 
Last edited:
on Phys.org
Actually... that first substitution may be flawed.
 
Ok, I think I see where I went wrong. The [itex]x_{0}[/itex] doesn't belong in the final answer.
 
yes, you've figured it out.

P.S. on this line, on the left hand side, there should be K since you have changed dy for dz:
[tex]N^{2} \int e^{-z^{2}} dz = N^{2} x_{0} K \sqrt{\pi}[/tex]
But after that you've remembered the K, so I guess you just forgot to type the K here, but you understand the right answer.
 
Yeah, I forgot about the K, so what I should end up with is:
[tex]N^{2} K \int e^{-z^{2}} dz = N^{2} K \sqrt{\pi}[/tex]