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amr55533
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Conservation of relativistic momentum and energy, pion decays
A small particle (pion), traveling at a velocity V, decays into two rays, γ1 and γ2. Find the Momentum and Energy of γ1 and γ2 if: a) γ1 is in line with V, and b) if γ1 is perpendicular to V.
I drew out the problem and listed all of the givens:
http://imageshack.us/a/img832/648/physprob.png
Eπ=Eγ1+Eγ2
Pπ=Pγ1+Pγ2
E=P*c (for rays, no mass)
E=mc^2/sqrt(1-V^2/c^2) (for particle)
E=K+E0
P=mV/sqrt(1-V^2/c^2) (for particle)
E0=mc^2
Below is my attempt at a solution so far:
http://img593.imageshack.us/img593/5444/solutionattempt.png
So far, I found:
m∏=2.406E-28 kg
V=2.827E8 m/s
Ebefore=405 MeV
Pbefore=382.1 MeV/c
I know that the total momentum after the particle decays has to equal the momentum before and same with the energy. I am just unsure how to finish the problem at this point.
Can I assume that Pγ1=Pγ2 after the disintegration?
I am also confused on how to handle part b) where γ1 is perpendicular to V.
Thanks in advance!
Homework Statement
A small particle (pion), traveling at a velocity V, decays into two rays, γ1 and γ2. Find the Momentum and Energy of γ1 and γ2 if: a) γ1 is in line with V, and b) if γ1 is perpendicular to V.
I drew out the problem and listed all of the givens:
http://imageshack.us/a/img832/648/physprob.png
Homework Equations
Eπ=Eγ1+Eγ2
Pπ=Pγ1+Pγ2
E=P*c (for rays, no mass)
E=mc^2/sqrt(1-V^2/c^2) (for particle)
E=K+E0
P=mV/sqrt(1-V^2/c^2) (for particle)
E0=mc^2
The Attempt at a Solution
Below is my attempt at a solution so far:
http://img593.imageshack.us/img593/5444/solutionattempt.png
So far, I found:
m∏=2.406E-28 kg
V=2.827E8 m/s
Ebefore=405 MeV
Pbefore=382.1 MeV/c
I know that the total momentum after the particle decays has to equal the momentum before and same with the energy. I am just unsure how to finish the problem at this point.
Can I assume that Pγ1=Pγ2 after the disintegration?
I am also confused on how to handle part b) where γ1 is perpendicular to V.
Thanks in advance!
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