Calculating Neutron Peaks with Increased Kinetic Energy

[NEWO]

hi,

in neutron scattering, if the lowest kinetic energy of a neutron is increased by a factor of 2, how do you work out the number of peaks produced?

I have worked out the lowest kinetic energy for a beta-brass CuZn to be 2.37meV using


E=\frac{\hbar^{2}k^{2}}{2m}[\tex] where <br /> <br /> k=\frac{2\pi}{\lambda}[\tex] and &lt;br /&gt; &lt;br /&gt; \lambda=2d\sin\theta[\tex]&amp;lt;br /&amp;gt; &amp;lt;br /&amp;gt; &amp;lt;br /&amp;gt; I would appreciate any help on this. &amp;lt;br /&amp;gt; &amp;lt;br /&amp;gt; thanks &amp;lt;br /&amp;gt; &amp;lt;br /&amp;gt; newo

 

[NEWO]

hmm my latex doesn't seem to work here, don't know why, can you get the gist of it?

 

[Hootenanny]

hmm my latex doesn't seem to work here, don't know why, can you get the gist of it?

You need to swap the back-slashes to forward slashes like this (without the spaces)

[ /tex ]

As for your question, how does this;

\lambda=2d\sin\theta

Relate to n? Remember than for the maximum n \Rightarrow \sin\theta = 1, also note that the number of peaks = n+1

 

[NEWO]

ahhh so

\lambda=nd\sin\theta

or am I missing something

 

[Hootenanny]

ahhh so

\lambda=nd\sin\theta

or am I missing something

Almost, I believe it is;

\lambda = \frac{d\sin\theta}{n} \Leftrightarrow n = \frac{d\sin\theta}{\lambda}

Can you see what happens if you increase the kinetic energy of the particle?

 

[NEWO]

yeah as the energy increases the number of peaks increases also

thanks for your help it is much appreciated

 

[Hootenanny]

yeah as the energy increases the number of peaks increases also

thanks for your help it is much appreciated

Sounds good to me. My pleasure