Neutron scattering - don't understand (1 Viewer)

[HNCS]

it's getting late in the year and our teacher is rushing through everything so i have a few questions

what is neutron scattering...and all this de broglie wavelength being influenced by mass and lack of charge?

perhaps it's because i don't understand de broglie......

But this syllubus point is confusing me.

Thanks for the help.

 

[thehootman]

http://en.wikipedia.org/wiki/Neutron_scattering

Basically, you shoot neutrons at a target nucleus, they bounce off and you can calculate the structure of the nucleus.

De broglie - everything with momentum has wavelength, and thus can be diffracted etc.

 

[samwell]

it's getting late in the year and our teacher is rushing through everything so i have a few questions

what is neutron scattering...and all this de broglie wavelength being influenced by mass and lack of charge?

perhaps it's because i don't understand de broglie......

But this syllubus point is confusing me.

Thanks for the help.

This whereby neutrons are used to study the structure of an atom because they have no charge and have a relatively similar mass to the protons. They are also more effective as they have a debroglies wavelength that is comparable to atomic spaces in crystal structure and they can travel slowly and stil reach the nucleus.

 

[Kings407]

de Broglie
E=hf
E=mc^2
hf=mc^2
c=fλ
f=c/λ
h/λ=mc
h/λ=mc
=p
Since an e/m wave such as light could also act like a particle - a photon, the energy of the photon could be related to both momentum and wavelength

Neutron Scattering
Braggs used X-rays to examine the crystal lattice structure. The wavelength of an x-ray is similar to the atomic spacings in the crystal lattice. Neutron scattering is the process of determining the structure and properties of matter through probing a material with thermal (slow) neutrons generated in research reactors and observing the way the nucei of the material's atoms scatter them. Basically they shoot neutrons at a target crystal - the same as in the Braggs experiement except they used X-rays and the Davison and Germer experiement except they aaccelerated electrons at a crystal.

Hope this helped.
I have a question now. How are neutrons accelerated? Or do they just get them from a nuclear reactor?

 

[tommykins]

Nuclear reactor I believe, since they ahve no charge you can't accerlate them pass thermal velocity.