Questions tagged [baryons]
Baryons are hadrons (particles composed of quarks) with an odd number, at least 3, of valence quarks. The term is also often used in astrophysics, e.g. "baryonic matter", with a much looser definition understood to mean any matter composed mostly of baryons, but which may also include leptons and other particles, often in opposition to "dark matter".
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Why do Baryonic acoustic oscillations imply peaks in the probability distribution of the position of galaxies?
I have been trying to understand baryonic acoustic oscillations (BAO) and there are some parts of the process I don't understand.
We start with a hot plasma of baryons and photons. There's also dark ...
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Must a very large nucleus be spherical?
As we do know, residual nuclear force has short distance action so there is no total center to rim nuclear force aggregation inside the nucleus as in the case of for example gravitation in the case of ...
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Experimental status/test possibilities for baryon number conservation in LHC?
Violation of baryon number is hypothesized e.g. for baryogenesis (more matter than antimatter from Big Bang) or Hawking radiation (baryons -> black hole -> massless radiation) - quite extreme ...
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When were the notions of "matter" (as opposed to mass) and its conservation introduced? [closed]
With the development of relativity it became clear that mass and energy are the same, and therefore that they aren't separately conserved (or balanced). It seems that during the same period when these ...
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What does it mean, during the Grand Unified Epoch, that matter fluctuated between lepton and baryon states?
My understanding of leptons and baryons is that leptons are an elementary particle, while baryons are a composite particle. Can someone explain to me what particles fluctuating between lepton and ...
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Where does the baryon number appear in the Lagrangian of the standard model?
In the standard model Lagrangian, the electric charges of the particles are the coefficients of the interaction terms (e.g. $(-2/3e)u'Au$ for the up quark shows it's charge is $(2/3)e $)
How can we ...
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Why do the ground state of baryons have symmetric spatial wavefunctions?
In Griffiths's Introduction to Elementary Particles (2nd edition), it is essentially said that the spatial part of the wavefunction of baryons in their ground state is symmetric w.r.t the interchange ...
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Mass of different isospin baryons
Why are the masses of baryons (of same quark content) with different isospin, different? - Is there a physical intuition/explanation to this? Does higher isospin baryons always higher mass than lower ...
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$\Sigma^0$ baryon decay
I’ve seen it stated that the sigma baryon $\Sigma^0$ only decays to $\Lambda^0 \gamma$, and then $\Lambda^0$ decays to $p\pi^{-}$ or $n\pi^0$.
I understand that the weak interaction conserves weak ...
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What is the connection between matter in the universe and the baryon number not being conserved?
Towards the end of "Quarks, the Stuff of Matter", the author discusses the implications of the proton is not stable and ultimately decays. He states, that if the proton decays, then the ...
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Why can't $uus$ and $uds$ quark content have $I = 1$ Isospin?
Well, I know the isospin singlet with $I=0$ and isospin triplet with $I = 1$. But for $I = 0$, why it must be $uds$ quark content rather than other assembly like $uus$ or $dds$? $ud$ can have $I = 0$ ...
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Which hadrons were present after the phase transition from the post-Big Bang QGP?
This question relates to the "hadron epoch" (after the initial quark-gluon plasma, but before the end of baryogenesis).
My understanding is that the phase transition that ends the quark-...
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Confusion about baryon number violation in the standard model
I'm reading Gauge Theory by David Tong and not understanding the concept of baryon number violation. I understand that the massless Dirac field has two symmetries, an $e^{i\theta}$ $U(1)$ symmetry and ...
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ELi5- How do pions hold nuclei together if they are so short-lived?
I need help understanding how particles do what they do and maintain the structures they maintain if so many of them exist for such a short time?
In the case of the nucleus and pions, pions only exist ...
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Octet and decuplet baryon wavefunction
I read the octet and decuplet baryons symmetric and anti-symmetric wavefunction from 'Riazzudin and Fiazzudin's book. But I am little confused about the wavefunction of neutral sigma and Lambda baryon....
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