The posible colors combinations of the mesons are red+antired, blue+antiblue and green+antigreen. The color+anticolor are not fixed, they “constantly” change. (Actually, any linear combination of the pairs is posible.) http://en.wikipedia.org/wiki/Quark#Strong_interaction_and_co...
There are some abstract algebraic properties of the particles and these properties produce the color rules.
With 4 quarks the only possibility is a mix of 2 quarks (with colors) and 2 antiquarks (with anticolors). For example red+antired+blue+antiblue.
Since 2008 researchers at Belle in Japan found hints of a four-quark particle. Those hints were confirmed.
"This reinforces the 5.1σ (4.7σ) rejection of the 2+ (2− ) hypotheses previously reported by the Belle collaboration, and confirms the 3.4σ (3.7σ) indications from Belle that 1+ is favored over 0− (1− )."
Belle collaboration, K. Chilikin et al., Experimental constraints on the spin and parity of the Z(4430)+ , Phys. Rev. D88 (2013) 074026, arXiv:1306.4894.
"The cost [...] has been evaluated, taking into account realistic labor prices in different countries. The total cost is X (with a western equivalent value of Y)" [where Y>X] source: LHCb calorimeters : Technical Design Report ISBN: 9290831693 http://cdsweb.cern.ch/record/494264
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[ 0.95 ms ] story [ 24.9 ms ] threadI thought the new particles were cool because they don't follow the color charge analogy, whereas mesons do follow the analogy?
There are some abstract algebraic properties of the particles and these properties produce the color rules.
With 4 quarks the only possibility is a mix of 2 quarks (with colors) and 2 antiquarks (with anticolors). For example red+antired+blue+antiblue.
"This reinforces the 5.1σ (4.7σ) rejection of the 2+ (2− ) hypotheses previously reported by the Belle collaboration, and confirms the 3.4σ (3.7σ) indications from Belle that 1+ is favored over 0− (1− )."
Belle collaboration, K. Chilikin et al., Experimental constraints on the spin and parity of the Z(4430)+ , Phys. Rev. D88 (2013) 074026, arXiv:1306.4894.
"The cost [...] has been evaluated, taking into account realistic labor prices in different countries. The total cost is X (with a western equivalent value of Y)" [where Y>X] source: LHCb calorimeters : Technical Design Report ISBN: 9290831693 http://cdsweb.cern.ch/record/494264
or: "1the western equivalent value is 1'390 kCHF. 2the western equivalent value is 5'450 kCHF" http://lhcb.ecm.ub.es/spd/spd/General%20information/spd_cost...