Calculating the lifetime of a particle

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    Lifetime Particle
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The discussion revolves around calculating the lifetime of a Δ particle formed from a pion and a proton, with a peak energy measurement of 1236 MeV and an experimental spread of 120 MeV. The relevant equation is ΔE*Δt ~ h-bar, where ΔE is interpreted as the experimental spread. Participants clarify that "experimental spread" is synonymous with "uncertainty," confirming its use in the calculation. The proposed solution involves using h-bar divided by the spread of 120 MeV to find the lifetime. This approach is deemed straightforward yet valid for determining the particle's lifetime.
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1. Homework Statement

A pi meson (pion) and a proton can briefly join together to form a Δ particle. A measurement of the energy of the ∏p system shows a peak at 1236 MeV, corresponding to the rest energy of the Δ particle, with an experimental spread of 120 MeV. What is the lifetime of the Δ?
A graph is given of the reaction probability as a function of energy, peaking at energy 1236 MeV. There are arrows on both sides of the peak labeled 120 MeV.


2. Homework Equations

ΔE*Δt ~ h-bar


3. The Attempt at a Solution
I am mainly unsure as to what an experimental spread is. My guess is that the experimental spread is equal to ΔE, and so the solution is simply (h-bar)/(120MeV), but that seems too simple.
 
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Hi Takuza! :wink:
Takuza said:
A pi meson (pion) and a proton can briefly join together to form a Δ particle. A measurement of the energy of the ∏p system shows a peak at 1236 MeV, corresponding to the rest energy of the Δ particle, with an experimental spread of 120 MeV. What is the lifetime of the Δ?

I am mainly unsure as to what an experimental spread is. My guess is that the experimental spread is equal to ΔE, and so the solution is simply (h-bar)/(120MeV), but that seems too simple.

Yup … "experimental spread" and "uncertainty" seem to mean the same :smile:
 
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