High-energy physicists predict new family of four-quark objects

High-energy physicists predict new family of four-quark objects
Beijing Spectrometer Detector Credit: The BESIII Collaboration

An international team of high-energy physicists says the discovery of an electrically charged subatomic particle called Zc(4020) is a sign that they have begun to unveil a whole new family of four-quark objects.

The Beijing Spectrometer (BESIII) collaboration, which includes scientists from UH Mānoa, previously announced the discovery of a mysterious four-quark particle called Zc(3900) in April 2013.

"While quarks have long been known to bind together in groups of twos or threes, these new results seem to be quickly opening the door to a previously elusive type of four-quark matter," said Frederick Harris, a professor of physics and astronomy at UH Mānoa, and a spokesman for the BESIII experiment. "The unique data sample collected by the BESIII collaboration has continued to yield a stream of clues about the nature of multi-quark objects."

The recent breakthroughs by the BESIII collaboration have come about through a dedicated study of the byproducts of the anomalous Y(4260) particle.

Using the Beijing Electron Positron Collider (BEPCII) in China, scientists tuned the energy at which electrons and positrons annihilate matter to 4260 MeV, which corresponds to the mass of the Y(4260) particle. The BESIII Collaboration used this method to directly produce and collect large samples of the particle's byproducts, or decays.

This experimental method allowed the BESIII collaboration to first observe the Zc(3900) and then the Zc(4020). Also recently spotted in the decays is the electrically neutral X(3872), a particle that has been experimentally established for more than 10 years, and has long been suspected to be a four-quark object.

High-energy physicists predict new family of four-quark objects
Using decays of the Y(4260), a family of four-quark objects has begun to appear.

"The year 2013 has so far been an exciting one for the BESIII experiment," Harris said. "Using decays of the Y(4260), a family of four-quark objects has begun to appear. While the theoretical picture remains to be finalized, more and more clues are suggesting that we are witnessing new forms of matter. And while a new 'zoo' of mysterious is emerging, it seems a new classification system may soon be at hand to understand it."

Explore further

Two collider research teams find evidence of new particle Zc(3900)

More information: The scientists have reported their findings to the scientific journal Physical Review Letters, including:

Observation of Z_c(4040) in e+e- —> D*D*- pi+ process at 4.26 GeV. arXiv:1308.2760

Observation of a charged charmoniumlike structure Z_c(4020) and search for the Z_c(3900) in e+e- to pi+pi-h_c. arXiv:1309.1896

Observation of a charged (DD*bar)- mass peak in e+e- —> pi+(DD*bar)-at Ecm=4.26 GeV. arXiv:1310.1163

Observation of the X(3872) in e+e- —> gamma pi+pi- J/psi at sqrt(s) around 4.26 GeV. arXiv:1310.4101

For more information, visit: www.phys.hawaii.edu/newsEvents … s/bes-pr-11-2013.pdf

Journal information: Physical Review Letters

Citation: High-energy physicists predict new family of four-quark objects (2013, November 8) retrieved 18 October 2019 from https://phys.org/news/2013-11-high-energy-physicists-family-four-quark.html
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Nov 08, 2013
Wonder if any of the new matter can be used for anti gravity shields?

Nov 08, 2013
This was reported about three or four months ago. Pretty interesting even though particle physics is something I've well versed in. Here's a link to an APS article that gives a little insight if anyone is interested.


Nov 09, 2013
I looked into quark size and black hole size real fast once and decided black holes are just a quark star compressed past the neutron star stage. I sent the word out but none of the people ever got back to me, found that kind of depressing. That was about 15 years ago....

Nov 09, 2013
"Wonder if any of the new matter can be used for anti gravity shields?" - Osiris1

Yes, and it will taste like strawberry ice cream.

Nov 09, 2013
"I looked into quark size and black hole size real fast once and decided black holes are just a quark star" - Botop

I am happy that you have decided this. Scientists can now move on to other things.

Would you also please decide that pi is identical to the square root of 10. Doing so will make the universe much more interesting.

Thank you in advance for your God-like abilities.

Nov 10, 2013
But he's actually right with it......... Thanks I never said I had the science down to a understanding, heck not even a fair one. But this was back in a time when string theory had no wheels to move on also. If string theory is right and gravity is open ended strings then they would have to bond to something and a "zero point" what the heck could ever bond to that? So there has to be something there. Better that a quark star is there then a gateway to ones lost sister baking apple tarts. After all we are talking of things we may never see so it all comes out in the math and that's my weakest link, and my best subject. I will admit it was a moment of spark then anything I ever worked out on paper. The only math I did on it was how many quarks could fit into the sphere of a given mass to make a black hole. Your the first person to have ever said I may be right, Thank you for that.

Nov 10, 2013
Well, Botopfbber (and it's spelt fibber, by the way) if math is your weakest link and your best subject, what the hell are you doing on this site? And how could you do the math for how many quarks could fit into the sphere of a given mass to make a black hole when the actual dimension of a quark has never been established? You can't use the size of a proton, since that is determined by the motion of its constituent quarks.

Nov 11, 2013
In general relativity all massive objects should collapse into singularity with no mercy. All right, but the general relativity isn't the only theory describing the world, the quantum mechanics is relevant as well.
*sigh* no it shouldn't, relativity isn't, quantum mechanics is, but it won't.
Apparently both theories are deeply flawed at the human observer scale.

meh, you're telling me all this stuff at submicroscopic scale doesn't work in daily life? Guess I then need to revise my slit experiment with basketballs for particles. such a shame. I'm so glad you came around, now we at least know we will have to keep to Newtonian physics, because it works so well at our scale.

Nov 12, 2013
1.) Must a four quark particle be integer charged? I am thinking of Millikan's measurement of 1/3 charge on some of the oil drops. Perhaps the color force is strong enough to allow non-canceling charges; in particular, within heavier nuclei, which might allow stability due to equivalent pressure, like the Lambda particle's stability within neutron stars.

2.) And less likely, might a four quark particle sustain a color charge? Personally, I think the lowest energy state would have cancelling colors / anti-color, but if the kernel of the four quark particle has cancelling colors, like a neutron and if the hadron had a low enough energy state, then the fourth quark could have a color charge, because flipping to an anti-color would require more energy.

Nov 13, 2013
The classification of unstable multiple quark objects could now be known as Vendiberries.

The four quark object to be known as the sub class Strawberries

Nov 14, 2013
I consider the possibility that this four-quark "particle" is probably a paired two-quark object. If anything, I think this lends proof that the quark is indeed the fundamental building block of subatomic particles, and that M-theory is bogus. Quarks can then only be reduced to chaotic energy fundamentals.

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