# about wavefunction and vector entries

I am beginer of physics and I am studying some very fundamental idea of quantum mechanics by myself. In the introducing book I am reading, there is an example to show a particle diffraced by a slit or something small then there show diffraction pattern. So if the wavefunction of the particle is represented in momentum space such that it has n entries in the wavevector so integer n stands for the nth diffraction order. So what's the significance of the square of the nth entry? Does it mean the probabilty of finding the particle with momentum diffracted into the nth order of the diffraction pattern?

Let's say I have a source of particles, each particle emitted at different speed towards the slit so they will be diffracted independently. How does the intial speed of each atom affect the diffraction pattern? If we look at the nth diffraction order, how will the speed of the particle change the probablity of finding the particle in the nth order?

Thanks a lot

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"it has n entries in the wavevector so integer n stands for the nth diffraction order" -- I'm not sure what this means. Reproduce the relevant equations in LaTeX here and we can take a look. –  MarkWayne Dec 6 '12 at 17:05