Questions tagged [leptons]
Leptons are elementary fermions that do not experience the strong interaction: electrons, muons, tauons, and neutrinos.
202 questions
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What would it mean for string theory if quarks and leptons turn out to be composite particles?
The smallest distances probed by human beings are about $10^{-21}$ m. This means that, relatively, still a considerable amount of space lies between this distance and the Planck-distance, $1,6\times ...
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Would muon atoms (i.e. atoms where every electron replaced with muon) effectively absorb gamma rays?
Particularly, in range of 0.5-3 MeV.
I'm talking about situations, when a single atom encounters gamma photon.
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Unstable Leptons: How are their rest masses (energies) calculated?
Six different leptons are known. Of these, two are unstable: the muon and tau lepton.
According to experimentally obtained data, the rest masses (energies) of these elementary particles are equal to ...
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Do we know empirically that electrons have no color charge?
Everything has a gravitational field, so everything is gravitationally charged.
Everything has an electromagnetic field (including quarks), so everything is electromagnetically charged.
Only quarks ...
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Is it possible to generate electricity from muons instead of photons?
I understand that solar panels generate electricity by converting photons from sunlight. This made me wonder whether it would be possible to use other types of cosmic radiation, such as muons, to ...
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Why a particle (specifically lepton) decays?
This is a sequel of my question. For particles with structure, it wouldn’t be strange for them to decay due to unstable structure and various reasons. But for leptons, such as the muon, it's almost ...
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What makes three generations of lepton so different in anomalous magnetic dipole moment?
I've read the questions discussing the differences among electrons, muons and taus. However, I am perticularly interested in their anomalous magnetic moment which seems not to be discussed in previous ...
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Understanding P&S bound state
Background:
In the bound state section by P&S (P.148-150), they compute the matrix elements for the transition of an ultra-relativistic electron-positron pair into a bound state of a muon-anti-...
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Can anyone tell me what the magnetic dipole moment of the muon is?
Is the magnetic dipole moment of the muon the same as the electron's ?
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Effect of particle charge on scattering amplitude
In QED, consider for example the scattering process $e^-\mu^- \to e^-\mu^-$, with the leading order Feynman diagram
(time flows from bottom to top).
The scattering amplitude is, using standard ...
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Diagonalize Yukawa Lagrangian
The Yukawa Lagrangain in the SM is:
$$\mathcal{L}_Y=\sum_{i,j=1,2,3} Y^\ell_{ij} \bar{L}^i\Phi \ell_{Rj}+Y^\nu_{ij} \bar{L}^i\Phi^c \nu_{Rj}+\text{h.c.}$$
where I've skipped the quark sector because ...
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What is the purpose of the MUon proton Scattering Experiment (MUSE)?
What is the purpose of the MUon proton Scattering Experiment (MUSE)? We know that when two protons collide together in a accelerator, convert to 4 muon ultimately (each proton decays to two muon)so is ...
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Is Lepton Flavour Universality (LFU) predicted by the Standard Model?
I'm trying to understand how LFU arises mathematically within the framework of the Standard Model. Is it a direct consequence of the theory, or is it simply an assumption or empirical observation ...
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How LEptons in Muonium are INteracting with Gravity? (LEMING-Experiment, Soter et al.)
How LEptons in Muonium are INteracting with Gravity? (LEMING experiment, Soter et al.)
I have read an article from the Physical Society Zurich, Switzerland about Prof. Dr. Anna Sótér planned LEMING ...
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Electron-muon scattering
I'm reading Mandl & Shaw Quantum field theory and am currently working my way trough chapter 7.4. Here they are talking about electron - muon scattering. They start of with the following ...
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