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New Subatomic Particle Discovered
Cyndi writes "A new subatomic particle has been discovered by researchers at Stanford. It seems to be "an unusual configuration of a charm quark and a strange anti-quark"."
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There's tons of different configurations of fundamental particles, especially quarks. Though the people who set up the accelerators and did this must be pretty chuffed, and have indeed contributed to the advancement of particle physics by helping repertoriate more of the possible combinations, there's nothing even remotely interesting to anyone who's not a particle physicist working on this type of quark configuration.
Now if they had discovered a new fundamental particle, or if that particle exhibited properties in contradiction with the current laws of particle physics (eg symmetry breaking), that would be worth posting...
Daniel
Carpe Diem
Might be a little too early in the morning. This guy is just a resonance of D_s+, which has a mass of 1968 MeV, and also is made up of c & s_bar. Naked charm just means the particle has a c and no c_bar, which is perfectly fine. Charmed particles have been around for a while now.
The combination was not the surprise, but the missing mass is, which suggests that the theoretical calculation of the binding force is incorrect (though such calculation is often an approximation themself) This usually signals that some aspect of the theory on the force is wrong or that their is yet another particle that was undetected, thus robbing some mass away. (Neutrino was 'discovered' this way)
This is a very simplistic response, but it'll have to do:
The situation you describe (two isolated/bare quarks or antiquarks, separated by a vast distance) can't really occur in the theory. It takes energy to separate the quarks/antiquarks in a subatomic particle; and because of the force getting stronger as the distance increases, it keeps taking more and more energy. As you separate the quarks, you're raising the potential energy of the system, just as if you were rolling a ball up the side of a bowl. Eventually you've put enough energy into the system to allow the creation of new particles -- specifically, a quark-antiquark pair, each member of which binds to the two quarks you're trying to separate, giving you two subatomic particles where before you had one (and still no bare quarks).
This phenomenon (among others) occurs all the time in particle accelerators in which hadrons (that is, particles made up of quarks and antiquarks) are collided, such as the Tevatron at Fermilab or the Large Hadron Collider at CERN. Protons at high energies collide with protons or antiprotons, and the input energies of the colliding particles provide the energy necessary for particle creation in the process described above.
What you suggest is similar to taking a ball, tying a bungee cord around it, and dropping it off a bridge. In the same manner, after a few oscillations, it would simply come to rest at the balance point between the two forces.
Hmm...I really can't tell if you are joking or not. This is never going to happen due to the scale at which these forces work. The strong nuclear force prevents free quarks from being observed. This is called confinement and is due to quantum chromodynamics (QCD). If a enough energy is pumped into a particle composed of quarks, the energy enevtually goes into creating a new quark pair, therefore satifying confinement (no free quarks). The amount of energy to do this is staggering. Think GeV or higher particle accelerator. Any other time the distances over which these forces work (10^-18 m) prevents much of anything being extracted.
Because the definition of a "particle" in this case is completely arbitrary. It's a charm and an antistrange quark in a bound configuration. You can 'imagine' it as the charm and the antistrange orbiting each other (though this isn't strictly true!) There's a 'ground state' for a D_s+, which is like 1970 MeV as I said above. This is an 'excited state'. In particle physics you call excited states new 'particles'.
We know we didn't 'invent' it because a c and an s_bar existed a long time before this guy. We just put them together in a weird way.