- #1
Matt atkinson
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- 1
1)
Alpha particles can react with 48-Ca to produce protons. Consider a beam of alpha particles of current 20nA fired at a think target of Ca of thickness $$1mg/cm^2$$. A detector subtending a solid angle of 4*10^-3 steradians, records 20 protons per second. Determine the total cross section (in mb) for the reaction. State any assumptions made.
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3)
So if I=20nA then the initial rate of alphas is:
$$R_o=\frac{I}{2e}=6.25 \times 10^{10} atoms / sec$$
And also the number of atoms in the think foil per $m^2$ is $$N=1.25\times 10^{23} atoms/m^2$$.
But I have no idea what to do from here I understand I'm given rate of initial alphas and rate of detection and a solid angle.
Could someone just point me in the right direction?
Alpha particles can react with 48-Ca to produce protons. Consider a beam of alpha particles of current 20nA fired at a think target of Ca of thickness $$1mg/cm^2$$. A detector subtending a solid angle of 4*10^-3 steradians, records 20 protons per second. Determine the total cross section (in mb) for the reaction. State any assumptions made.
2)
3)
So if I=20nA then the initial rate of alphas is:
$$R_o=\frac{I}{2e}=6.25 \times 10^{10} atoms / sec$$
And also the number of atoms in the think foil per $m^2$ is $$N=1.25\times 10^{23} atoms/m^2$$.
But I have no idea what to do from here I understand I'm given rate of initial alphas and rate of detection and a solid angle.
Could someone just point me in the right direction?
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