Modern Physics: Charge of Discovered Particles

[Theus_ferreira]

TL;DR

Do all particles have charge whose value is an integer multiple of the elementary charge?

I am studying Modern Physics at graduation and several new particles are being presented, which I had not any contact with until now. I'm wonder if all these particles, which were recently discovered by Physics, have charge whose value is a multiple of the elementary charge of the electron or if there is an exception?

 

[PeterDonis]

Do all particles have charge whose value is an integer multiple of the elementary charge?

No. Quarks don't; they have charges that are multiples of 1/3 of the electron charge.

I am studying Modern Physics at graduation and several new particles are being presented

Which particles are these? And from what source are you learning? (A reference to whatever textbook or other reference you are using would help.)

 

[mfb]

All free particles, yes. But not all particles - quarks have integer multiples of 1/3 the elementary charge. They can't exist as isolated free particles, however, they always* form hadrons that have integer multiples of the elementary charge.

*excluding quark gluon plasmas, but there they are not isolated either

 

[vanhees71]

Even in the QGP you have not really free partons (quarks and gluons) either, because they are still "strongly coupled" (at least at the fireball temperatures/densities reachable in heavy-ion collisions and even in neutron-star mergers, where you have amazingly similar properties of the strongly interacting matter as at heavy-ion collisions in the energy regime probed in the beam-energy scan at RHIC and in the near future at FAIR).

The parton-like degrees of freedom describing approximately a QGP under these conditions are rather constituent quarks (quark-like quasiparticles) and gluon-like quasiparticles (though even the quasiparticle picture is a bit too idealized, because models indicate that the effective degrees of freedom in the QGP in this regime have pretty large "thermal width").