Тяжёлые адроны ФИАН / 9
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Flavor Physics
Тяжелые адроны
лекция 9
Sergey Polikarpov
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Overall mesons list |
https://pdglive.lbl.gov/Viewer.action |
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Light unflavoured mesons (ud, uu, dd, ssbar):
π±, π0, η, η’, η(1405)…, ρ±, ρ0, ρ(1450)…, ω(782), ω(…), f0(980), f0(…), f1(…), f2(…), φ(1020), φ(…) ….
Strange mesons: K±, K0 (KS, KL), K*(892)±, K*(892)0, K*(…), K1(…), K2(…), … Charm mesons: D±, D0, D±s, D*(2010)±, D*(2007)0, D*±s , D1(…)±,0, D*±s0,1,2(…)
Beauty mesons: B±, B0, B0s, B*±, B*0, B*0s, B1(5721)±, B1(5721)0, B*2(5747)0, BJ(…), Bs1(5830)0, B*s2(5830)0, … Beauty charm mesons: B±c, Bc(2S)±, B*c(2S)±,
Hidden charm mesons: ηc(1S), ηc(2S), J/ψ(1S), ψ(2S), ψ(3770), ψ2(3823), ψ(…), χc0(1P), χc1(1P), …, χc2(1P), hc(1P), X(3872), X(4140)… Zc … Y…
Hidden beauty mesons: ηb(1S), ηb(2S), Υ(1S), Υ(2S), Υ(3S), Υ(4S), Υ(5S), χb0(1P), χb1(1P), χb2(1P), χb1(2P),
χb1(3P), χb2(3P), … Z+b
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Overall baryons list |
https://pdglive.lbl.gov/Viewer.action |
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N(…) up to J=11 !! |
Δ(…) |
Strange baryons Λ [uds] , Σ+ uus, Σ− dds, Σ0 uds, Λ(…), Σ(…)
Doubly strange baryons Ξ− [dss], Ξ0 [uss], Ξ(…)
Triply strange baryon Ω− [sss], Ω(…)−
Charm baryons: Λ+c, Σ+c, Σ++c , Σ0c, Ξ+c, Ξ0c, Ω0c
Beauty baryons: Λ0b, Σ0b, Σ+b, Σ−b, Ξ0b, Ξ−b, Ω−b
Doubly-Charm baryons: Ξ+c+c, Ξ+cc , Ω+cc , Ω+c+cc
Doubly beauty baryons: homework
Beauty-Charm baryons: homework
Triple-Charm baryon: homework
Triple-Beauty baryon: homework
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Exotic hadrons
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Exotic hadrons
Since we have a good theoretical control on the spectrum of pure cc¯ (charmonia) and b¯b (bottomonia) states, any hidden charm or bottom state not fitting in the theoretical spectrum is a good candidate for being an exotic, multiquark state. These unanticipated charmonia or bottomonia are the X and Y mesons discovered in the last two decades, the first examples being the X(3872) meson discovered by Belle in 2003 and the Y (4260) meson, discovered by BaBar in 2005.
Charmonia before 2003 |
Charmonia ~2020 |
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X(3872) Belle 2003
2400 цитирований!
Blue boxes: predicted and discovered charmonium states; gray boxes: predicted conventional charmonium states but
https://inspirehep.net/literature/627760 |
not yet discovered; red boxes: neutral non-conventional XYZ mesons; magenta boxes: charged non-conventional states. |
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Exotic hadrons
Production:
- In e+e- collisions (Belle, BaBar, CLEO, BESIII, etc):
- from photon with JPC = 1 – – (+ maybe ISR photon)
-the two-photon fusion,
-double charmonium production
-In pp collisions (LHC, Tevatron): any state (but huge bkg)
-From B hadron decays in all experiments
Current (old) naming scheme
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The Y(4260) and the Y(4230) states
BaBar searching for X(3872) in |
but observed instead Y(4260) |
2005 |
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Confirmed later by Belle and CLEO
https://inspirehep.net/literature/686354
Dip ?? Interference?
Y(4260) = molecule, a hybrid, or a tetraquark ??
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The Y(4260) and the Y(4230) states
BESIII
https://inspirehep.net/literature/729388 https://inspirehep.net/literature/733344 |
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https://inspirehep.net/literature/756012 https://inspirehep.net/literature/756643 |
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The Y(4260) and the Y(4230) states
first observation of an open charm decay for the Y(4230) state.
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The Y bottomonium states
Much less studied, since yields are much lower
Belle was studying Υ(10860) and Y(11020) states, assumed to be Υ(5S) and Υ(6S)
more data:
Found a bump at 10750 MeV
At the same time,
Showed a dip at the same energy!
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