Kinetic energy of daughter nucleus and alpha particle from alpha decay

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SUMMARY

The discussion focuses on the kinetic energy of the daughter nucleus and alpha particle resulting from alpha decay. The equations governing this process are derived from the conservation of momentum and kinetic energy, specifically: Mαvα + MYvY = 0 and (1/2)Mαvα² + (1/2)MYvY² = Q. The expressions for the kinetic energies of the decay products are given as Eαk = (MY/(MY + Mα))Q and EYk = (Mα/(MY + Mα))Q. The key to solving the problem lies in rearranging the expression for Q and factoring it appropriately.

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Homework Statement


In \alpha decay a nucleus X at rest decays to a daughter nucleus Y and an \alpha particle. Conservation of momentum and kinetic energy gives:
M_{\alpha}v_{\alpha}+M_{Y}v_{Y}=0

\frac{1}{2}M_{\alpha}v_{\alpha}^{2}+\frac{1}{2}M_{Y}v_{Y}^{2}=Q

Where the Q value is the available energy found through Q=(M(X)-M(Y)-M(\alpha))c^{2}

Show the kinetic energy of the two decay products are given by

E^{\alpha}_{k}=\frac{M_{Y}}{(M_{Y}+M_{\alpha})}Q

E^{Y}_{k}=\frac{M_{\alpha}}{(M_{Y}+M_{\alpha})}Q


Homework Equations


\frac{1}{2}M_{\alpha}v_{\alpha}^{2}+\frac{1}{2}M_{Y}v_{Y}^{2}=Q

M_{\alpha}v_{\alpha}+M_{Y}v_{Y}=0

Q=(M(X)-M(Y)-M(\alpha))c^{2}

E^{\alpha}_{k}=\frac{M_{Y}}{(M_{Y}+M_{\alpha})}Q

E^{Y}_{k}=\frac{M_{\alpha}}{(M_{Y}+M_{\alpha})}Q

The Attempt at a Solution


I have tried rearranging the energy equation to get E^{\alpha}_{k}=Q-\frac{1}{2}M_{Y}v_{Y}^{2}
since
E^{\alpha}_{k}=\frac{1}{2}M_{\alpha}v_{\alpha}^{2}

Then rearranging the conservation of momentum equation and substituting in for various variables but I can't get anything that looks like the required expressions. I know this is a fairly simple algebra exercise but I just can't figure out what to do so any advice or suggestions would be appreciated.
 
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I managed to figure this out. I rearranged the expression for Q to get E^{\alpha}_{K}like in my initial attempt but then I took Q out as a common factor which was the key. It was then just a matter of doing about 3 pages of algebra on what was inside the brackets.
 

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