Fundamental Particles - Meson Decay Question

AI Thread Summary
The discussion centers on the decay of the pion-zero meson into two gamma rays and the calculation of their energy and wavelength. The user initially calculated the energy of the meson as 2.16 x 10^-11 J and halved it for the two gamma rays, resulting in 1.08 x 10^-11 J. Using the equation E = hc/λ, the user found a wavelength of 1.84 x 10^-14 m, which differs from the book's answer of 1.98 x 10^-14 m. Another participant confirmed the user's calculation, suggesting the book may be incorrect, leading the user to accept their result as valid. The conversation highlights the complexities of particle physics calculations and potential discrepancies in reference materials.
Magda|A380
Messages
5
Reaction score
0

Homework Statement


The pion-zero meson has its mass quoted as 135.0MeV/c2.
It decays into two gamma rays:
∏0 → γ + γ
b) Assuming the ∏0meson to be initially at rest, calculate the energy and hence the wavelength of the two gamma rays.

Homework Equations


E= hc/λ

The Attempt at a Solution


Part a) just wanted me to calculate the mass in kg; which was fine, but I'm having trouble with part b).
E = 135.0 MeV, which I get to be 2.16x10-11J
I halved this value as there are two gamma rays, to get 1.08x10-11J
Using this value for E in the equation E=hc/λ, my value for λ is 1.84x10-14; however according to my book the answer should be 1.98x10-14
Could someone please tell me where I'm going wrong?
Thank you :smile:
 
Physics news on Phys.org
Hello Magda|A380,

Welcome to Physics Forums!
Magda|A380 said:

Homework Statement


The pion-zero meson has its mass quoted as 135.0MeV/c2.
It decays into two gamma rays:
∏0 → γ + γ
b) Assuming the ∏0meson to be initially at rest, calculate the energy and hence the wavelength of the two gamma rays.

Homework Equations


E= hc/λ

The Attempt at a Solution


Part a) just wanted me to calculate the mass in kg; which was fine, but I'm having trouble with part b).
E = 135.0 MeV, which I get to be 2.16x10-11J
I halved this value as there are two gamma rays, to get 1.08x10-11J
Using this value for E in the equation E=hc/λ, my value for λ is 1.84x10-14; however according to my book the answer should be 1.98x10-14
Could someone please tell me where I'm going wrong?
Thank you :smile:
For what it's worth, I calculated the same answer that you did (λ = 1.84 x 10-14 m, to three significant figures).
 
collinsmark said:
Hello Magda|A380,

Welcome to Physics Forums!

For what it's worth, I calculated the same answer that you did (λ = 1.84 x 10-14 m, to three significant figures).

Thanks collinsmark :)
Yeah, my books is known to be wrong sometimes and 1.84 x 10-14 m still lies within the gamma ray wavelength range; so I'll accept it as the correct answer.
 

Thread 'Rolling without slipping on a curved surface'

Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
View full post »

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'Correct statement about a reservoir with outlet pipe'

Thread 'Correct statement about a reservoir with outlet pipe'

The answer to this question is statements (ii) and (iv) are correct. (i) This is FALSE because the speed of water in the tap is greater than speed at the water surface (ii) I don't even understand this statement. What does the "seal" part have to do with water flowing out? Won't the water still flow out through the tap until the tank is empty whether the reservoir is sealed or not? (iii) In my opinion, this statement would be correct. Increasing the gravitational potential energy of the...
View full post »

Similar threads

Finding the total energy of a Pi meson
Replies
15
Views
3K
I How often would a ϕ meson decay to a electron-positron pair?
Replies
2
Views
2K
Conservation Laws and Symmetries Particle Physics
Replies
3
Views
3K
How can I calculate the rate of energy absorption from nuclear decay?
Replies
23
Views
2K
Special Relativity and Decaying Particles
Replies
3
Views
3K
How Do You Calculate the Kinetic Energy of Particles in Relativistic Decay?
Replies
3
Views
3K
Possible webpage title: How does energy factor into the decay of particles?
Replies
2
Views
1K
Muon production and decay from relativistic annihilation
Replies
4
Views
2K
Relativity with energy and momentum question
Replies
4
Views
3K
Finding the velocity of an emitted particle from a decay
Replies
3
Views
2K

Hot Threads

Recent Insights

Back
Top