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bbbl67
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Would baryons not made with standard Up or Down quarks exhibit smaller radii than neutrons and protons? I'm thinking like for example how muons have much smaller orbitals than electrons, on the lepton side of things.
I suppose all of those radii would do. What's the difference between them?malawi_glenn said:What radii? Mean charged radii, mass radii?
Here is a paper with results from calculating mean charged radius-squared, their results are that those baryons indeed have smaller values than the proton.
https://link.springer.com/article/10.1007/JHEP05(2014)125
Here is another paper https://arxiv.org/abs/0810.1021
There is also a repulsive force from the gluons when quarks get too close. Do higher-mass quarks run into that limit if they get too close? Or is the gluon interaction distances different for these other quarks?Meir Achuz said:I will talk mostly about the stable octet baryons, because excited baryons can have vastly different radial states. The distance between two quarks in a spin zero state is smaller than the distance in a spin one state because of the spin-spin interaction of quarks. This is why the Delta has a larger radius than the nucleon, and the Lambda has a smaller radius. There is a longer range, Coulomb-like, force between quarks that would give a smaller radius to heavier quarks. That is why the Xis have a smaller radius than the nucleon. The spin-spin interaction is not large for charmed and bottom baryons. That is why they tend to have a smaller radius than the nucleon.
the mass radii is a bit "speculative" though there are some peer-reviewed papers trying to calculate it.bbbl67 said:I suppose all of those radii would do. What's the difference between them?
Source? The gluon exchange is asymptotically free at short rage https://en.wikipedia.org/wiki/Asymptotic_freedombbbl67 said:There is also a repulsive force from the gluons when quarks get too close
Would this be to figure out if they would be stable inside super-neutron stars?malawi_glenn said:the mass radii is a bit "speculative" though there are some peer-reviewed papers trying to calculate it.
it is basically about gravitational interactions.
https://journals.aps.org/prd/pdf/10.1103/PhysRevD.104.054015
https://journals.aps.org/prd/pdf/10.1103/PhysRevD.105.096033
This graph:malawi_glenn said:Source? The gluon exchange is asymptotically free at short rage https://en.wikipedia.org/wiki/Asymptotic_freedom
That is the force between two nucleons, not between two quarks. The force between two nucleons is modeled with meson exchange, not gluon exchange. The repulsive part of the nucleon-nucleon force is due to vector-meson exchange (like ω) iirc.bbbl67 said:This graph:
No.bbbl67 said:Would this be to figure out if they would be stable inside super-neutron stars?
Ah, I didn't notice that! I had assumed it was the force within a nucleon, i.e. between quarks.malawi_glenn said:That is the force between two nucleons, not between two quarks. The force between two nucleons is modeled with meson exchange, not gluon exchange. The repulsive part of the nucleon-nucleon force is due to vector-meson exchange (like ω) iirc.
Okay, so the EM force becomes important again even within the hadron?malawi_glenn said:The force between two quarks become weaker at shorter distances.
In Baryons, you would have quarks with same sign of their charge, so due to their electric replusive force you will at some point not be able to push two quarks closer (in some kind of classical analogy).No.
The force at moderate distances that affects the mass is Coulombic, like the so called 'Cornell potential'.malawi_glenn said:The force between two quarks become weaker at shorter distances.
Higher-mass quarks do not directly affect the size of baryons. The size of a baryon is primarily determined by the strong nuclear force between the quarks, which remains constant regardless of the quark's mass.
No, the size of a baryon is determined by the number and type of quarks it contains, not their individual masses. Therefore, higher-mass quarks would not result in smaller baryons.
No, increasing the mass of all quarks would not necessarily result in a decrease in baryon size. The size of a baryon is determined by the strong nuclear force between the quarks, not their individual masses.
Yes, there are other factors that can affect the size of a baryon, such as the number and type of quarks it contains, as well as the energy of the system. These factors can influence the strength of the strong nuclear force and therefore impact the size of the baryon.
No, the size of a baryon is primarily determined by the strong nuclear force between the quarks, not their individual masses. Therefore, lower-mass quarks would not necessarily result in larger baryons.