Explore BrainMass
Share

# Questions of Elementary Particles

This content was STOLEN from BrainMass.com - View the original, and get the already-completed solution here!

See attached file for full problem description.

3.13 A pion traveling at speed v decays into a muon and a neutrino, pi^- --> mu^- + v_mu. If the neutrino emerges at 90 degrees to the original pion direction, at what angle does the mu come off?

3.14 Particle A (energy E) hits particle B (at rest), producing particles C_1, C_2, ... A + B --> C_1 + C_2 + ... + C_n. Calculate the threshold (i.e., minimum E) for this reaction, in terms of the various particle masses.

https://brainmass.com/physics/gamma/elementary-particles-neutrino-masses-neutrino-muon-51265

#### Solution Preview

Please see the attached files for proper formatting.

Let us take units in which the speed of light \$c = 1\$, and put c back in the final answer, in such cases where it is there, to make it easier to write formulae.

noindent
bf 3.13 rm

Let the incoming pion velocity direction be along X-axis, and neutrino direction be along Y-axis, then the 4-momenta of the pion and neutrino
\$\$
p_pi = m_pigamma(1, beta, 0, 0),
\$\$
and
\$\$
p_nu = ...

#### Solution Summary

This solution uses step by step calculations and formula to solve the given problems.

\$2.19

## Particle & Astronomy Questions

1. What is a particle accelerator? How do scientists use particle accelerators to study subatomic particles?
2. What particle is exchanged to generate each of the four fundamental forces?
3. What medical technologies (e.g. PET) rely on the physics of elementary particles?
What are the benefits of noninvasive procedures such as PET?
4. How is astronomy the oldest science?
5. How does the energy produced at the core of the Sun reach the photosphere?
6. Why won't the Sun become a supernova or black hole?
7. Why does the existence of the cosmic redshift lead to the big bang picture of the universe?
8. If a galaxy is 1,000 Mpc away, how fast is it receding from us?
9. The average temperature of the universe is 2.7 Kelvin. What is that temperature in degrees Fahrenheit?
10. The Milky Way has a radius of approximately 100,000 light years. How many miles is that? How long would it take you to travel across our galaxy if you were traveling at 50% the speed of light

View Full Posting Details