Decay - How does this notation represent a reaction?

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The discussion focuses on interpreting the notation for a nuclear reaction involving boron-10 undergoing alpha decay and subsequent beta-plus decay. The initial assumption was that boron-10 reacts with an alpha particle to produce lithium and helium, but it was clarified that the correct product is nitrogen-14, which then releases a proton to form carbon-13. The notation used is noted to be specific to nuclear astrophysics, which can simplify complex reaction chains. The final products are identified as having an atomic mass number of 13 and an atomic number of 6 for carbon. Understanding this notation is essential for accurately representing nuclear reactions in astrophysical contexts.
phyzmatix
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Homework Statement



\mbox{What is the atomic number Z, the atomic mass number A, and the element X in the reaction} \ _{5}^{10}B(\alpha,p)_{Z}^{A}X

Homework Equations



If my understanding of the question is correct, then we are dealing with alpha decay and beta-plus decay.

The Attempt at a Solution



I can't find an example of this notation for the reaction in my textbook, so I assumed that it meant:

_{5}^{10}B \ \mbox{undergoes alpha decay and the resultant product undergoes beta-plus decay to form} \ _{Z}^{A}X

And got the following:

_{5}^{10}B \ \mbox{undergoes alpha decay}

_{5}^{10}B \rightarrow _{3}^{8}Li + ^{4}He

\mbox{and} \ _{3}^{8}Li \ \mbox{undergoes beta-plus decay}

p \rightarrow n + e^+ + v

\mbox{So,} \ _{3}^{8}Li \ \mbox{transforms as follows}

_{3}^{8}Li \rightarrow _{2}^{8}He + e^+ + v

\mbox{Finally,} \ A = 8, Z = 2, X = He.

Please tell me if my interpretation of the notation (and subsequently my reasoning) is indeed correct.

Thanks
phyz
 
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This notation is peculiar to nuclear astrophysicists, I think; I'm not sure other nuclear physicists notate reactions quite that way. (It's handy, though, when you have to write down the various chains of reactions that take place in stars, since some of the reaction networks can run to dozens of processes...)

So most people would write <br /> \ _{5}^{10}B + \alpha \rightarrow p + _{Z}^{A}X. There are 14 nucleons involved here, 7 of them being protons, so the product should have 13 nucleons, of which 6 are protons.

Your first step should be a combination of boron-10 with an alpha particle, to produce nitrogen-14:

<br /> _{5}^{10}B + _{2}^{4}He \rightarrow _{7}^{14}N .

Apparently, the nitrogen-14 is "excited" and releases a proton, leading to

_{7}^{14}N \rightarrow _{1}^{1}p + _{6}^{13}C .

Since the nitrogen nucleus doesn't exist for long, it is simply omitted here and the net reaction alone is presented.
 
dynamicsolo said:
This notation is peculiar to nuclear astrophysicists, I think; I'm not sure other nuclear physicists notate reactions quite that way. (It's handy, though, when you have to write down the various chains of reactions that take place in stars, since some of the reaction networks can run to dozens of processes...)

So most people would write <br /> \ _{5}^{10}B + \alpha \rightarrow p + _{Z}^{A}X. There are 14 nucleons involved here, 7 of them being protons, so the product should have 13 nucleons, of which 6 are protons.

Your first step should be a combination of boron-10 with an alpha particle, to produce nitrogen-14:

<br /> _{5}^{10}B + _{2}^{4}He \rightarrow _{7}^{14}N .

Apparently, the nitrogen-14 is "excited" and releases a proton, leading to

_{7}^{14}N \rightarrow _{1}^{1}p + _{6}^{13}C .

Since the nitrogen nucleus doesn't exist for long, it is simply omitted here and the net reaction alone is presented.

Thank you very much for an excellent explanation.

(Turns out it's a good thing I asked hey? :wink:)
 
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