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Physicists Discover "Doubly Strange" Particle
Tsalg writes "Physicists have discovered a new particle made of three quarks, the Omega-sub-b. The particle contains two strange quarks and a bottom quark (s-s-b). It is an exotic relative of the much more common proton and weighs about six times the proton mass. This is probably one of the last noticeable sub-atomic discoveries made somewhere else than at CERN since LHC is about to start the hunt for the Higgs particle that remains elusive even for the experiment that just discovered the Omega-sub-b."
Sometimes I think physicists are just making things up. This is one of those times.
Can someone translate that last sentence for me?
Because you can - or because you should?
...that's strange.
Ok I thought quarks, leptons, and neutrinos were grouped like this:
Group 1: quarks; Up & Down, lepton; electron, neutrino; neutrino
Group 2: quarks; Charm & Strange, lepton; muon; neutrino; muon neutrino
Group 3: quarks; Top & Bottom, lepton; tau, neutrino; tau neutrino
So this newly discovered particle is made of quarks from two groups, the strange quark from group 2 and the bottom quark from group 3. Has that been seen before? I never knew it happened.
Equine Mammals Are Considerably Smaller
you don't want to see what the Japanese quarks are up to.
Bukkuarke?
If libertarians are so opposed to effective government, why don't they all move to Somalia?
That was my immediate thought too. Perhaps LHC emits some sort field that causes all other particle accelerators to mysteriously stop working. Yes, that must be it. European particle physics experiments are heavily influenced by fundamental particles called eurons and LHC has been sucking them up at a vast rate to the detriment of other experiments.
All I want is a secure system where it's easy to do anything I want. Is that too much to ask ~~ Randall Munroe
"The measurement of the mass of the Omega-sub-b provides a great test of computer calculations using lattice quantum chromodynamics"
Discuss ; )
"Kill 'em all and let Root sort 'em out"
OK, so I have been reading a lot about particle physics lately and find the whole subject fascinating, but there is one thing (amongst many things) that I am not quite understanding. I have looked it up and my understanding of particle physics is not "there" yet, or at least not enough to grasp this particular concept. Maybe I have just not read the right explanation.
Can someone in here put it in a simple lamen explanation?
The question is this:
This Omega-sub-b particle contains two strange quarks and a bottom quark and weighs about six times the mass of a proton.
A proton contains 2 up quarks and one down quark.
Strange quarks have a mass of 95MeV, bottom has 4.2GeV so the total mass of the Omega-sub-b would be 4.39GeV
Up quarks have a mass of 3MeV, down has 6MeV so the total mass of a Proton would be 0.012GeV
This would put the Omega-sub-b at 365.8 times the mass of a Proton.
So I am obviously not understanding how the masses of the quarks correlate to the masses of the fermions. What am I missing here?
Thanks,
Tom...
...doubly strange, some quirks, and six times overweight.
Ed, you're famous!
Perhaps LHC emits some sort field
In Richard Florida's book Who's your city? he actually gets into various theories about how centers of excellence (whether fashion, IT, finance, science, etc.) tend to create a self-reinforcing "buzz" that draws in more and more talented people, and the intellectual atmosphere and other elements of creative infrastructure then allow those people to achieve at a higher level than they otherwise could.
...
So according to that theory, yes, the LHC does emit some sort of field
If libertarians are so opposed to effective government, why don't they all move to Somalia?
Must be an American particle.
Who knows? Perhaps that's why they're yet to be discovered: that we haven't reached the right energies. Well, the LHC will reach far higher energies than anything else on earth. Every time there's been a substantial step up in collision energies, all manner of new particles fall out. That alone makes the LHC favourite to dominate the field for the foreseeable future. That's before you consider the fact that a project of this scale, with absolutely enormous long-term funding, attracts everyone. The best particle physicists in the world are going to be attracted to working on the LHC, or on analysis of the data it produces.
There'll still be discoveries made elsewhere, but for the headline stuff, watch CERN.
Real Daleks don't climb stairs - they level the building.
Won't happen. We're hard at work on it right now (except when we're reading slashdot...), and we're making some amazing leaps forward in analysis techniques, but we simply won't have enough data to be sufficiently sensitive to the Higgs by the time the accelerator shuts down. We might find evidence or even strong evidence, but not strong enough to call it discovery. We do have enough data to exclude certain mass ranges, however. When you combine our data with D0's (the experiment that did the analysis in TFA), we have enough sensitivity to say that the Higgs, if it is the standard model Higgs (and the lightest SUSY Higgs is sufficiently similar that this holds for it, too), does not have a mass quite close to 170 GeV (which is pretty close to the mass of the top quark, incidentally). http://www-d0.fnal.gov/Run2Physics/WWW/results/prelim/HIGGS/H64/
SIGSEGV caught, terminating
wait... not that kind of sig.
Ever since deep inelastic scattering experiments revealed that the proton is not a pointlike charge at sufficiently small electron wavelengths, but rather scatters electrons as if it contained three pointlike (at that scale) charges (+2/3, +2/3, and -1/3), quarks have generally been considered real. Prior to these experiments, there most certainly was ontological debate about quarks. There was also similar debate about atoms for quite some time (see Ernst Mach).
SIGSEGV caught, terminating
wait... not that kind of sig.
I was always fascinated by particle physics but it's been a while since I studied it. Can someone explain how a proton-antiproton collision (u,u,d quarks and anti-u,anti-u,anti-d quarks) could produce strange quarks? I thought all that was left after a matter-antimatter collision was x-rays and gamma-rays.
You missed it. It already happened 500 years ago but the activation caused some strange time dilation effects meaning that we're all stuck in 2008, and whenever you hear about someone planning a party, you've already missed it.
which is totally what she said
The proton weighs a little under a GeV, most of which is binding energy. Since the u and d quarks have so little mass, you can effectively ignore it and look at the dynamical relationship of 3 bound quarks. This is why early models which treated protons and neutrons as different states of the same particle (called isospin symmetry) worked so well. The equation's not all that simple, since binding energy is itself a function of the masses of the quarks involved. The only real theoretical calculations are heavily computational lattice QCD simulations, and experiments like this are a good test of those calculations.
As a sidenote, the headline makes very little sense. We observed a "triply-strange" particle, the original Omega, ages ago. What makes this special aren't the two s quarks per se, but their appearance alongside a bottom quark.
IAAPP
Of course they are sharing the raw data. But understanding the raw data means understanding a great deal about the physical structure of the detector. Basically, if you know enough about that, you are part of the CERN team, whether you are physically there or not. Relatively few of the thousands of scientists working "at" CERN are physically there at any time: most spend most of their time connected only electronically. Why do you think the WWW was invented there?
Consciousness is an illusion caused by an excess of self consciousness.