(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Alpha particle with kinetic energy 6MeV is scatterd on gold nucleus (A=197).

Is Rutherford cross-section formula valid for this scattering? Explain !

2. Relevant equations

3. The attempt at a solution

The Coulomb barrier is Ec=(1.03MeV)*(Z1*Z2)/(A1^1/3+A2^1/3)

Z1=79 , Z2=2 , A1=197 , A2=4

Ec=1.03MeV*158/7.41=22MeV

The 6 Mev alpha particle will not go through the barrier, forces between alpha particle and gold nucleus will be coulombic so I think it is valid to use Rutherford cross-section.

But I found that Rutherford cross-section formula is valid if

[tex]Z1*Z2*\alpha<<1[/tex] is true.Since for Z1=79,Z2=2,alpha=1/137 this is not <<1 ,

so rutherford cross-section is not valid.

Where I'm going wrong?

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# Homework Help: Rutherford scattering problem

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