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I think that you have to neglect the s-quark mass not its momenta in your expression. Anyway, if you perform the standard procedure for calculating this integral you will find an expression which is a function of all the possible external momenta and the metric tensor as well. Then you can carry the limit $p_s \to 0$ you will find the formula which are you ...


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The spatial wavefunction is $Y_L^m(\theta,\phi)$. When exchanging the two particles, the spatial wavefunction becomes to $Y_L^m(\pi-\theta,\pi+\phi)$. Mathematically, we have $Y_L^m(\pi-\theta,\pi+\phi)=(-1)^L Y_L^m(\theta,\phi)$. If $L$ is odd, the spatial part is antisymmetric, otherwise symmetric. BTW, you may post this question as a comment of the ...


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The Higgs mass does not stem from eating Goldstone bosons, since the Higgs is not a gauge field. Since we are breaking an $\mathrm{SU}(2) \subset \mathrm{SU}(2)_L \times \mathrm{U}(1)_Y$ completely, we have three Goldstone bosons, which are eaten by three of the four electroweak gauge bosons to form the massive $W^\pm,Z$ with the photon remaining massless. ...


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I think the short answer is that they mix, because nothing prevents them from not doing it. The fact is that states with equal quantum numbers in general do mix. The experiment will tell you how much they mix. If you find a very or almost zero mixing you can start thinking to add a symmetry that prevents some mixing to happen, which was the case of a lot ...


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All the experimentally observed particles that are believed to be fundamental particles, but for neutrinos, in the Standard Model get a mass from the interaction with the Higgs boson. Please note that this aspect of the dynamics of the Standard Model is still under experimental investigation, despite there is data that clearly points towards this direction. ...


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It is mainly measurement and detector errors that make up the width in the plots you show. The Monte Carlo simulates the detector resolution and folds in the theoretical values when it says that the width agrees. The real width is expected to be much smaller. In this we see that the real width is only given as a bound by the experiments the CMS ...


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The decay width of a particle is antiproportional to its lifetime. Looking at the partial width of the $H \rightarrow \mu \mu$ decay, one could expect that the lifetime of the Higgs is large. This would be correct, if the Higgs could only decay to muons. In other words: The Higgs decaying to muons has a low probability (a low branching ratio). This comes ...


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Acceptance is some measure of the fraction of events or the spacial or momentum distributions of events that will be registered in the detector. The exact meaning varies from experiment to experiment and sometimes from analysis to analysis within a single experimental data set. Understanding the acceptance of a experiment for a particular signal can be a ...


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If you assume that whatever generates the mixing patterns of quarks and leptons (beyond the SM) has no underlying symmetry and that nature chose $V^{CKM}$ and $V^{PMNS}$ randomly within the set of $3\times3$ unitary matrices, then it is natural to expect mixing between families because the probability of randomly selecting $V^{CKM}=V^{PMNS}={\mathbb 1}$ is ...


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Exactly as you mention in the second part of your post. Leptogenesis takes place at temperatures higher than the electroweak scale $T_{EW}\simeq100\,\mbox{GeV}$. Therefore, heavy neutrinos decay into lepton and higgs doublets, whose fields are still all physical.


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A) What is the piece of theory which dictates that electrons interact via the weak force with other electrons and protons, and how can this force be understood in terms of what I am more familiar with i.e a coulombic interaction and dipole moments ... Electrons interact via the electromagnetic force dominantly with other electrons and protons, not the ...



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