Normalization Constant for Gaussian

atomicpedals
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Homework Statement



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

Homework Equations


1 = \int |\psi (x)|^{2} dx

The Attempt at a Solution


1 = \int |\psi (x)|^{2} dx = N^{2} \int e^{-(x-x_{0})^{2}/K^{2}} dx
Substitute y=(x-x_{0})
N^{2} \int e^{-y^{2}/K^{2}} dy
Substitute again z = y/|K|
N^{2} \int e^{-z^{2}} dz = N^{2} x_{0} K \sqrt{\pi}
N= ( \frac{1}{K x_{0} \sqrt{\pi}})^{1/2}
Where my question lies is with the x_{0} in N. Should that be there?
 
Last edited:
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Actually... that first substitution may be flawed.
 
Ok, I think I see where I went wrong. The x_{0} 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:
N^{2} \int e^{-z^{2}} dz = N^{2} x_{0} K \sqrt{\pi}
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:
N^{2} K \int e^{-z^{2}} dz = N^{2} K \sqrt{\pi}
 
yep, looks right to me :)
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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