All Questions
Tagged with standard-model leptons
85
questions
3
votes
0
answers
46
views
Is there a sigma for unexplained hypothetical discoveries?
I recently read that the Koide formula relating electronic leptons rest masses is often considered to be numerologic, since unexplained, even though recent years experiment data tend to narrow the ...
3
votes
1
answer
285
views
How to be sure that when a muon passes a detector it is actually a muon?
The question is as follows: when you have any kind of detector for muons you just take measurements and you say, for example, the number for the muon flux but how you're sure that all particles ...
1
vote
1
answer
96
views
How was the tau lepton predicted?
I know the tau lepton has been predicted before it was discovered – unlike the muon. But how does our theory (SM/electroweak theory) predict the existence of a third lepton generation?
- 11
3
votes
1
answer
82
views
Would it be possible to generate muons using neutrinos and electrons?
The decay products for a muon are an electron, a muon neutrino, and a electron antineutrino. As the decay products for a neutron (electron, proton, neutrino) can combine together to form a neutron ...
2
votes
2
answers
81
views
Can exchange interaction exist between electron and muon? [closed]
I'm studying about the exchange interaction and it's quite confusing.
Why does it happens between same kinds of particle?
How about electron and muon? Or one particle and another one which has all the ...
- 57
7
votes
5
answers
2k
views
What happens when an anti-electron collides with a neutrino?
What happens when an anti-electron collides with a neutrino? If something does happen, is a photon released after the collision?
- 81
0
votes
1
answer
133
views
How would I estimate the partial width for the decay of upsilon meson into an electron-positron pair?
I cam across a question that stated the total decay width for the phi meson was 4300 kev and the partial decay of it into an electron-positron pair was 1.3kev. How would I estimate the partial width ...
- 39
0
votes
1
answer
96
views
Why is the branching fraction of strange $D$ mesons to tau leptons so high?
From the PDG (https://pdg.lbl.gov/2008/listings/s031.pdf & https://pdg.lbl.gov/2010/listings/rpp2010-list-Ds-plus-minus.pdf) the branching rate for strange D mesons to tau leptons is about 3 ...
- 11
1
vote
2
answers
432
views
Can tau decay into a pair of charm and strange quarks?
I found on wikipedia that tau can decay to hadrons made of quarks and it seems like a tau can only decay to a pair of down and anti-up quarks. I understand that tau (1.8GeV) doesn't have enough mass ...
- 99
2
votes
0
answers
111
views
How is the $SU(2)_L$ conjugation applied?
I'm reading a paper where they introduce the lepton doublets $L$ and "their $SU(2)_L$ conjugations" $\tilde{L}$, which I'm guessing means
$$
\tilde{L} = i\sigma_2L^*.
$$
After $\textit{vev}$,...
- 525
-4
votes
1
answer
188
views
What charge does muon have? [closed]
I have a simple $\mu$-meso atom model. Kernel is just one proton and on orbit there's one muon, which is 210 times heavier than electron. What charge does it have? I checked some tables about muons ...
0
votes
1
answer
156
views
Chirality in muon decay
Consider the muon decay process:
We assign the chirality according to the $W$ boson current: (i.e. P&S eq.(20.80))
$$J_W^{\mu+}=\frac{1}{\sqrt{2}}\bar{\nu}_{\mu L}\gamma^{\mu}\mu_L \quad J_W^{\mu-...
- 1,421
0
votes
1
answer
142
views
What particles existed in the Planck, GUT, and electroweak epochs, respectively?
What quarks, leptons, and bosons existed in each of the individual epochs of the early universe (Planck, GUT, electroweak)? Did the quantum zoo gain or lose species during these times? Or did some of ...
- 325
0
votes
2
answers
238
views
The Dirac equation predicted the positron. Does the Dirac equation also suggest the existence of muons?
The Dirac equation is given by:
$$ (i\partial \!\!\!/ - m) \psi(x) = 0$$
It famously predicted positrons by suggesting negative energy solutions. First it was solved with the 'Dirac sea' and positrons ...
- 2,035
5
votes
1
answer
179
views
Is the muon superfluous?
When the muon was discovered, it was so unexpected that Rabi's reaction was, "What? Who ordered that?" The muon doesn't play any obvious role in the behavior of protons, neutrons, and ...
rob♦
- 91.5k