Why More W^+/- than Z^0 in Proton-Antiproton Collisions?

  • Context: Graduate 
  • Thread starter Thread starter evilcman
  • Start date Start date
  • Tags Tags
    Boson Z boson
Click For Summary
SUMMARY

In proton-antiproton collisions, the production of W^+/- bosons significantly exceeds that of Z^0 bosons due to several factors. The presence of more u ubar pairs compared to u dbar pairs enhances W boson production. Additionally, the coupling strength of the Z boson to quarks is lower than that of the W boson, which contributes to the disparity in their production rates. Furthermore, W bosons can be produced from both u ubar and u dbar collisions, while Z bosons are limited to u ubar interactions.

PREREQUISITES
  • Understanding of proton-antiproton collision dynamics
  • Familiarity with W and Z boson properties
  • Knowledge of quark-antiquark pair interactions
  • Basic concepts of particle physics coupling constants
NEXT STEPS
  • Study the role of parton distribution functions (PDFs) in particle collisions
  • Learn about the differences in coupling constants for W and Z bosons
  • Explore the process of photon decay into W boson pairs
  • Investigate leading-order (LO) calculations in particle physics
USEFUL FOR

This discussion is beneficial for particle physicists, researchers in high-energy physics, and students studying the interactions of fundamental particles in collisions.

evilcman
Messages
40
Reaction score
2
Can someone give me a qualitative/handwaving argument of
why much more W^+/- boson are produced in proton-antiproton
collisions compared to Z^0 bosons?

PDFs are not enough to explain this I believe, since we will have more
u ubar pairs in the collision than u dbar...

Also if I remember correctly the coupling for the Z-2fermion
vertex is higher with a factor of 1/sin(theta_W). Well the vertices
are kinda different so this is not so simple.

Is there an easy way to guess this or one has to do a full LO calculation
or something?
 
Physics news on Phys.org
First thought, don't know if its the dominant effect.

Z can be produced in the first vertex, but all such vertices can also produce a photon. The photon couples to W's but not to Z and therefore the photon can decay into a pair of W's.

This means that W's can be produced both by u ubar and by u dbar, while Z only get produced by u ubar collisions.

cheers!
 
1) The Z is heavier.

2) The Z's vector coupling to quarks is less than the W's.
 

Similar threads

Graduate W+/W- bosons ratio in proton-proton collision
  • · Replies 5 ·
Replies
5
Views
3K
Undergrad Why Does the Higgs Boson Prefer to Decay into W Bosons Over Z Bosons?
  • · Replies 2 ·
Replies
2
Views
2K
Graduate Why Do W and Z Bosons Have Different Masses?
  • · Replies 14 ·
Replies
14
Views
4K
Graduate Branching ratios | Higgs phenomenology
  • · Replies 13 ·
Replies
13
Views
4K
Undergrad How powerful would a collider have to be to observe a sphaleron?
  • · Replies 2 ·
Replies
2
Views
3K
Graduate Why are W and Z bosons considered force carriers?
  • · Replies 13 ·
Replies
13
Views
6K
Graduate What Happens in a Proton-Antiproton Collision at High Energies?
  • · Replies 2 ·
Replies
2
Views
31K
Graduate What is electron? Is it a perfect point? What does it mean?
  • · Replies 10 ·
Replies
10
Views
3K
Mathematica This Week's Finds in Mathematical Physics (Week 244)
  • · Replies 1 ·
Replies
1
Views
3K