Z boson Definition and 26 Threads

If I look at the photon propagator <A_mu (x) A^nu(0) > in momentum space, as I understand it I am to compute this by summing up all the self-energy diagrams of the photon, which look like: photon -> stuff -> photon In particular, since the photon shares the same quantum numbers as the Z, you...

I am a student minor in physics and I am taking this course of particle physics. And I have been lost since the Non-Abelian Gauge Theory which a few lectures before Electroweak unified Theory lecture. i am completely confused and overwhelmed by the math since the mid-term exam, since I was not...

Hi The diagram I am referring is shown at 1:45 of this classic Symphony of Science tune Thanks, Cal

If a Z can decay to a photon, what happens to the Z's weak charge?

Considering a Z boson decay into a fermion-antifermion pair. How can i say if the process respect parity and charge conjugation?Thanks

Hi All 1. Homework Statement with the known coupling strenght between SM neutrinos and Z boson Z_{\mu} \bar{\nu}_{L} { \gamma}^{ \mu} \nu_{L} how can I get the coupling strength for Dirac neutrinos Z_{\mu} \bar{\nu}_{Dirac} { \gamma}^{ \mu} (1- { \gamma}_{ 5} ) \nu_{Dirac} ? thanks

Homework Statement Calculate the ratio ##R = \frac{\sigma_{had}}{\sigma_{\mu+\mu-}}## for energy around ##10~GeV##. At sufficiently high energies, the ##e^+e^- \rightarrow \mu^+ \mu^-## reaction can proceed via the ##Z^0## boson. Assuming vertex factors for EM and weak interaction are the same...

Hi there, my question is the following. If an electron and positron annihilate, how can they result in ZZ? The issue I'm having is that due to charge conservation, the exchange particle can't be W- or W+. It also can't be a photon since the Z's don't have electrical charge to couple to. It...

The Standard Model formula for the cross-section of ##e^+e^-\rightarrow\mu^+\mu^-## is made up of 3 components: QED interactions, weak interactions, and electroweak interference. I understand the behaviour of the QED part, and the resonance that occurs in the weak part at ##\sqrt{s}=M_Z##, but...

I've seen explanations that when a neutrino with a W+ Boson comes near a neutron, it affects one of the bottom quarks and changes it to a up quark which effectively turns the neutron into a proton. The neutrino then turns into an electron. Source: (2:20 onwards) I've seen other explanations...

I have read that the Z boson cannot change the flavour of a particle. So my assumption is that an interaction such as: usanti -> udanti + Z Is not possible, is this correct?

Hi all, I have a question about simulating (Monte Carlo) proton-proton collisions resulting in, for example, a Z boson. Assume two quarks (quark and antiquark) from each proton collide head-on along the z-axis. The quark momenta are distributed according to the Parton Density Functions...

Hello everyone, I have read about the theoretical values of the Z boson decay partial width and how well they agreed with experiment. However there is something I do not quite understand: since these theoretical calculations were performed with the hypothesis that the masses of the decay...

Could someone please tell me what the symbols in the Zee.csv file mean on the CERN webpage (https://cms-docdb.cern.ch/cgi-bin/PublicDocDB/ShowDocument?docid=11581)? I am doing a project for my statistics class and that information would be useful. I'll appreciate any and all help.

What are the accepted numbers for the decay rate and lifetime of Z-> mu+mu- and Z-> e+e- decays? also what is the unit for the decay rate? thank you!

Why does the Z boson only decay to fermion-antifermion pairs? I'd just like to understand the basic reason why something like Z --> anti-down, strange wouldn't work. This would conserve charge. It obviously wouldn't conserve strangeness, but the weak interaction doesn't, so I'm just wondering...

Homework Statement One of the mediators of the weak interactions is the Z boson, which has a mass of 91 GeV/c 2. Use this information to find an approximate value for the range of the weak interaction. Homework Equations This is the part that I am having trouble with. I don't know where to...

I was always wondering, on very short distances/high energies, what is a net effect of having not one (gamma) but two (gamma and Z) 'carriers' for the 'force' between 2 charged particles. Does it make an interaction sronger or not?

Hi just wondering if anyone could tell me why the Z boson can couple to any standard model particle except forgluons and photons?

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...

Hi I can't find a Feynman rule for the coupling of two Z bosons to a photon. Does the Z boson couple to a photon at all?

Suppose I want to find the minimum velocity of the electron and positron required to make a Z boson during annihilation. How would I go about this? I had an attempt which came out at 422ms^-1. This doesn't really seem right... so I'm guessing i made a big mistake...

Question leads on from others where s^1/2 = 200GeV mH = 70GeV EH = 91.5GeV and p = 59GeV, (three momentum). The reaction was e+e- -> HZ0 where H is higgs boson and Z0 is the Z0 boson with mass 91GeV It says the Z0 decays to two muon and antimuon. They are observed to be equal energy in...

I need help understanding the Higgs mechanism: what is the Higgs condensate, what is the Higgs boson, why do only the W and Z bosons have mass, and how exactly do particles receive mass? thanks guys!

Hi! I was wondering how W+/- pairs can be created in an electron/positron collider. Does the e+e- form a Z^0 which decays to W^- W^+ ? http://www.particle.kth.se/zlab/project/Elep.gif I have found this picture, but there is no info about the mediating particle (in the small...

Why was is it needed to include the Z boson along with the W's... is the theory nonrenoramalizable without it?