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New Particles X(3872) Y(4260) X(3940) University of Hawai’i Future of Heavy Flavors ИТЗФ 7/23-24/06 Z(3930) Y(3940) Ѕтефан Олавич ????
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B-factories are Charmonium factories cc production mechanisms @ a B factory: B meson decays e + e - annihilation collisions e + e - radiative return (isr)
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cc production in B decays j=½ J = 0 or 1 Spectator model says J cc = 0 or 1 should dominate exclusive B K(cc) decays.
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Allowed decays all have Bf~10 -3 from PDG2004 c K 0.9 x10 -3 J K 1.0 x10 -3 J/ K* 1.4 x10 -3 ’ K 0.7 x10 -3 ’ K* 0.9 x10 -3 c0 K 0.6 x10 -3 c1 K 0.7 x10 -3 J/ K 1270 1.8 x10 -3 B K cc(J=2) still not seen
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e + e - J/ + (cc) J/ X X (almost) always contains (cc) C(X) = +1 consistent with bkg c c c0 c’c’ M(X)
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DD J PC = 0 ++, 2 ++ J PC = 1 -- c e + e - (cc)
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XYZ particles in Belle X(3872) – J/ in B K J/ Z(3930) –DD in DD Y(3940) – J/ in B K J/ X(3940) – e + e - J/ X & e + e - J/ DD* Y(4260) – J/ in e + e - J/ NEW
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Z(3931) DD at Belle 41 11 evts (5.5 ) M=3931 4 2 MeV 20 8 3 MeV sin 4 (J=2) Matches well to c2 ’ expectations M(DD) GeV Belle PRL 96, 082003 (2006)
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Z(3930): candidate for the c2 ’ 3931 M= 3931 MeV is ~45 MeV low =20MeV too narrow? Masses from Barnes, Godfrey & Swanson PRD 72, 054026 (2005)
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e + e - J/ X(3940) e + e - J/ + X hep-ex 0507019 submitted to PRL
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X(3940) D*D seen ( DD & J/ not seen) D B(D*D)>45% B(DD)<41% From X(3940) → D * D: M = (3943 ± 6 ± 6) MeV < 52 MeV at 90%CL
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Is the X(3940) the c ”? 3940 M= 3943 MeV is ~150 MeV low <52MeV too narrow?
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X(3872) in B K J/ M( J ) ’ J/ X(3872) J/ PRL 91, 262001
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Also seen in pp X(3872) CDF hep-ex/0406022 11.6 Production properties similar to those of the ’ X(3872) D0 PRL 93, 072004 (2004) PRL 93, 162002 (2004)
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C=+1 is established X(3872) J/ seen in: & Belle PRL 96 102002 M( looks like a X(3872) ” ”J/ seen CDF Belle hep-ex/0505037
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ll |cos l | 2 /dof = 34/9 |cos | |cos | 2 /dof=34/9 0 ++ 0 -+ rule out 0 ++ & 0 -+ J k x J Ruled out by Belle
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Angular analysis from CDF Ilya Kravchenko: FPCP06 1 ++ or 2 -+
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Belle: Threshold peak in B KD 0 D 0 0 M=3875.4 0.7 0.8 MeV Br(B KX)Bf(X D 0 D 0 0 ) = (1.27 0.31 )x10 -4 Br(X D 0 D 0 0 ) Br(X J/ ) ~ 10 +0.7 -1.7 +0.22 -0.39 M(DD ) EE Belle hep-ex/0606055 today!
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Comments on the D 0 D 0 0 mass peak Fitted M: 3875.4 0.7 0.8 MeV +0.7 -1.7 M–(m D0 + m D*0 ) = + 4.3 0.7 MeV +0.7 -1.7 PDG05 2xPDG error on m D0 (could be 2.0 MeV) PDG M X3872 : 3871.2 0.5 MeV Here error on m D0 drops out Nominally ~2.3 above D 0 D* 0 threshold (but errors are non-Gaussian) ~2 discrepancy DD* “Binding Energy?”:
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X(3872) has no satisfactory cc assignment 3872 r J/ too small & r ( J/ ) too big c1 ’ c J/ ispin forbidden D 0 D 0 0 @ thresh. suppressed B Kcc(J=2) suppressed c2
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Y(3940) in B K J/ M≈3940 ± 11 MeV ≈ 92 ± 24 MeV PRL94, 182002 (2005) M( J/ ) MeV (Y 3940 J/ > 7 MeV (an SU F (3) violating decay) ~ this is 10 3 x ( ’ J/ (another SU F (3) violating decay) if the Z(3930) is the c2 ’ the Y(3940) mass is too high for it to be the c1 ’
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Is there a cc slot for Y(3940) ? Can M( c1 ’)>M( c2 ’)? c1 ’ Mass is low c”c” “ “ c0 ’ 3940 3931
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e + e - isr Y(4260) at BaBar 233 fb -1 e e + J/ pb (Y4260 J/ ) > 1.6MeV @ 90% CL Y(4260) X.H. Mo et al, hep-ex/0603024 4260 BaBar PRL95, 142001 (2005) Not seen in e + e - hadrons BES data
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Y(4260) at CLEO-III Consistent results 13.3 fb -1 ISR (1S)- (4S) 13.3 fb -1 70 +40 588 23 +6 Width (MeV) 4283 +17 44259 8 +2 Mass (MeV) 14.1 +5.2 (4.9 )125 23 (~8 ) N CLEO IIIBaBar-6 -16 -4 -4.2 -25 R.Poling @ Charm 2006
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Y(4260) at Belle MXMX Select e+e- ℓ + ℓ - +X; N chg =4 M ℓ + ℓ - =M J/ 30MeV; p J/y >2 GeV; M >0.4GeV | data 4.2<M J/ <4.4 MC M=4295 10 +11 MeV = 133 26 +13 MeV -6 -5 Preliminary For ’ J/ in the same data: M( ’) = 3685.3 0.1 MeV (PDG: M( ’)=3686.09 0.04)
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BaBar vs CLEO vs Belle BaBarCLEO IIIBelle (Preliminary) N 125 23 (~8 )14.1 +5.2 (4.9 ) 165 24(stat) (>7 ) Mass(MeV) 4259 8 +2 4283 +17 4 4295 10 +11 Width 88 23 +6 70 +40 5 133 26 +13 -6 -4 -4.2 -16 -25 -6-6 different “Full” report from Belle at ICHEP in Moscow -5-5
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No 1 -- cc slot for the Y(4260) 4280 X.H. Mo et al, hep-ex/0603024
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DD** threshold in relation to the “Y(4260)” 4.28-m D D** spectrum M( J/ ) GeV No obvious distortions
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Another one from BaBar? (4352) ’ (produced via radiative return)
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summary Z(3931) ( DD) –Probably the c2 ’ X(3940) (e + e - J/ X) –C=+1 –Could be the c ” (albeit with some stretching) X(3872): –J PC = 1 ++ –Br(X J/ ) large –Br(X D 0 D 0 0 ) seen; ~ 10xBr(X J/y) D*D
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summary cont’d Y(3940) – ( Y 3940 J/ ) >7 MeV too large for charmonium – Mass too low for a hybrid “Y(4260)” –Confirmed by Belle but at a higher mass – (y 4260 J/ )>1.6 MeV also very large – J PC =1 --, but not seen in e + e - hadrons - Straddles the D**D threshold, but with no obvious distortions to the J/ line-shape 233 fb -1
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conclusions There is a new hadron spectroscopy in the 3.5~4.5 GeV mass region –Maybe more than one The new states are characterized by large partial widths (Bfs) to hadrons+J/ – Br(X(3872) J/ ) > 4.3% (Isospin=1) – (Y(3940) J/ ) > 7 MeV (SU(3) octet) – (Y(4260) J/ ) > 1.6 MeV There is no apparent transition at the D**D mass threshold (mine, not Belle’s)
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Thank You
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Back-up slides
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Look at e + e - J/ D(D ( * ) ) Reconstruct a J/ & a D use D 0 K - + & D + K - + + Determine recoil mass
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Inclusive B Kx from BaBar ? Fully reconstructed B - tags
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M
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