News from BES III 1 st Observation of

News from BES III & 1 st Observation of the b(2 S) by Belle Stephen Lars Olsen Seoul National University Meeting of the Kor. Q Working Group SNU, April 21, 2012

Evidence for light non-qqmesons _ 1) The “light” scalar-meson nonet JP=0+ 800 k 0 k+ 800 The “light” scalar mesons 980 a 0 - 800 980 k- f 0 a 0 0 600 _ k 0 a 0+980 800 2) Too many “light” scalar-mesons: , f 0(980), f 0(1370), f 0(1500), f 0(1710), f 0(1790), …

The f 0(600) (the “ ”) From a Partial Wave Analysis of J/ + BESII PLB 598, 149 (2004) J/ ↳ J/ b 1 ↳ ↳w M( ) pole position: (541± 39) – i(252± 42) Me. V J/ f 2 ↳

K 0 (the “k ”) ± (800) From a Partial Wave Analysis of J/ K+ 0 KS with either M(K+ 0) or M(KS -) = M(K*±) ± 80 Me. V BESII PLB 693, 88 (2010) J/ K*K* _ J/ K*K 2* _ J/ KK 1(1270) _ J/ K*k ↳K 1 -- 2++ ↳K 0++ k pole position: (849± 77+18 -14) – i(256± 40+46 -22) Me. V

Signals for f 0(980) & K+K- BESII PLB 607, 243 (2005) f’ 2(1525)+f 0(1710) K+Kf 0(980) K+K- strong f 0(980)_ coupling to KK g =4. 2± 0. 3 f 0(980) + - f 2(1270)+f 0(1370) + f 0(1790) + -

Signal for a 0(980) K+K- Belle Collab: 0 PRD Belle 80, 032001 (2009) a 0(1450) ( 0) Crystal Barrel Collab: PRD 57, 3860 (1998) a 0(980) K+K- a 0(980) ( 0) a 0 0 strong a 0(980) coupling to KK g =1. 03± 0. 14

light scalar nonet masses are inverted pseudoscalars typical scalars unique Also: § No “light” JP=1+ and 2+ partner nonets in the same mass range. _ § In qq meson nonets, the I=0 state (here the a 0(980)) has no s-quarks. § m(f 0(980)) m(a 0(980)) implies “ideal” mixing & small s-quark content in f 0(980). _ strong couplings of the a 0(980) & the f 0(980) to KK indicate strong OZI-rule violations

If not qq, then what? _ Possibilities that have been suggested: loosely bound meson-antimeson “molecule” _ tightly bound diquark-diantiquark _ q s_ s q K _ q_ In color space: red+blue=magenta (antigreen) A colored diquark is like a antiquark s cl _ “nu rce fo ear” q s K* cyan+yellow=green (antimagenta) A colored diantiquark is like a quark R. L. Jaffe PRD 15, 267 (1977) J. D. Weinstein & N. Isgur PRD 27, 588 (1983)

f 0(1370) f 0(1500) f 0(1710) f 0(1790) f 0(980) 2) Too many light 0++ scalars? f 0(600) or : f 0(980): f 0(1370): f 0(1500): f 0(1710): f 0(1790): BESII PLB 607 (2005) 243 PLB 603 (2004) 138 PLB 598 (2004) 149 PRD 68 (2003) 052003 PLB 642 (2006) 441

Mixing with a scalar glueball? Idea available long time ago, a recent analysis in PRD 71, 094022 (2005) By Frank Close and Qiang Zhao s G n f(1710) f(1500) f(1370) The mass of the scalar glueball is about 1. 461. 52 Ge. V in this scheme.

Institute of High Energy Physics -- Beijing -- I BESII C P BE To Tiananmen Square (~10 km)

BEPCII storage rings Beam energy: 1. 0 - 2. 3 Ge. V Peak Luminosity: Design: 1× 1033 cm-2 s-1 Achieved: 0. 65 x 1033 cm-2 s-1 Beam energy measurement: Using Compton backscattering technique. Accuracy: d. Ebeam/Ebeam ≈ 5 10– 5 d. Ebeam ≈ 50 Ke. V @Ebeam ≈ m 12

luminosity since startup Note that luminosity is lower at J/ , and machine is optimal near (3770) Integrated luminosity: Jan. 2009– June 3 2011 about 4. 0 fb-1 @ different energies Note increase in slopes! 2011: (3770) & (4040) for Ds 2010: (3770) 2009: & J/ November 26, 2011 Hai-Bo Li (IHEP) 13

BESIII’s 1 st event

BESIII Collaboration 11 Helmholtz Institute Mainz Johannes Gutenberg-University Mainz Turkey: Turkish accelerator center 29 >300 physicists 49 institutions from 10 countries

Data samples collected: – 225 M J/ – 106 M ’ – 2. 9 fb-1 (3770) – 0. 5 fb-1 @4010 Me. V Tentative future running plans: 2013: Ecm=4170 Me. V: Ds physics + R scan (Ecm > 4 Ge. V) 2014: ’/ /R scan (Ecm > 4 Ge. V) 2015: (3770): 5 -10 fb-1 for DD physics _ This year: mass scan ~500 M ’ events ~1 B J/ events

Some new results on light scalars

a 0(980)0 f 0(980) mixing N. N. Achasov, S. A. Devanin & G. N. Shestakov, Phys. Lett. B 88, 367 (1979) isospin violation enhanced by K 0 – K+ mass difference 2 m. K+ = 987. 4 Me. V expect a narrow line shape: ≈2(m. K 0 -m. K+)=7. 8 Me. V 2 m. K 0 = 995. 2 Me. V PDG 2010: Mf 0= 980 ± 10 Me. V f 0= 40 ~ 100 Me. V 2 m. K+ 2 m. K 0 Ma 0= 980 ± 20 Me. V a 0= 50 ~ 100 Me. V

BES study of a 0(980)0 BESIII PRD 83, 032003 (2011) f 0(980) mixing

a 0(980)0 f 0(980) mixing results _ KK molecule model 90% CL upper limits different models & parameterizations Statistics limited, but we should have lots more data soon

J/ f 0 0 (980) , f 0(980) BESIII ar. Xiv: 1201: 2737 ( PRL) last week! (1405) from helicity analyses f 0(980) + f 1(1285) 3. 7 1 st observations: (1405) f 0(980) 0 & J/ gf 0(980) 0 Large Isospin violation: (1405) f 0(980) 0 0 f 1(1285) 1. 2

comparison: Isospin violations in ’ J/ ’ + - 0 J/ ’ 0 0 0 BESIII preliminary

Anomalous f 0(980) lineshape in (1405) f 0(980) 0 BESIII ar. Xiv: 1201: 2737 Fitted mass: M”f 0” = 989. 9 ± 0. 4 Me. V ”f 0” = 9. 5 ± 1. 1 Me. V The peak is midway between 2 m. K 0 & 2 m. K+ & width ≈ 2(m. K 0 - m. K+ ) PDG 2010: Mf 0= 980 ± 10 Me. V f 0=40 ~ 100 Me. V

Effect of Triangle Singularity? J. J. Wu et al, ar. Xiv: 1108. 3772 Triangle Singularity (TS) 1405 _ _ K*K and KK are on shell enhancing TS contribution and isospin violation a 0—f 0 mixing 1405 a 0—f 0 mixing is too small to explain anomaly by itself

Some puzzles in J/ and ’ decays

1 st evidence for ’ decays to 0 & 4. 6 4. 3 BESIII PRL 105, 261801 (2010) x 10 -6

the - ’ mixing angle q. P SU(3): Cahn & Chanowitz PLB 59, 277 J/ : CLEOc: PRD 79, 111101 ’: BES III: PRL 105, 261801 PDG: -200 < q. P < -100

Rate for c 1 V( , , ) too large? BESIII <10. 5 228± 13± 16 <20. 8 <12. 9 69. 7± 7. 2± 5. 6 <6. 1 <16. 2 25. 8± 5. 2± 2. 0 <8. 1 1 st observation BESIII PRD 83, 032003 (2011) “hadronic loop corrections? ”: ar. Xiv: 1005. 0066; EPJC 70, 177 (2010)

Polarization of c 1 V( , , ) Longitudinal polarization ( f L ); Transverse polarization ( f T); q : Helicity angle AL dominates, consistent with theoretical prediction Z. Phys. C 66, 71 (1995) 29 Phys. Rev. 77, 242 (1950)

the old - puzzle, with a new twist Reminder: c d u - J/ ( ) c u d + PDG: R( ) = 0. 2 %

J/ + - 0 & ’ + - 0 in BES III BESIII preliminary J/ ’ no events! most of the events!

baryon & baryonium(? ) spectroscopy

’ pp _ BESIII preliminary Very clean N*(1535) p signal PWA result Mass: Ge. V N(1535) PWA result M(pp) _ PWA: JPC = ½- _ Ge. V M 2(pp) Width: M 2(p ) Br( ' N(1535)p) Br(N(1535) p +c. c. ) _ = M(p )

from a 2007 talk at Hirschegg: BES II: near-threshold KL mass enhancement in J/ p. KL _ _ N X* BES II PS, eff. corrected (Arbitrary normalization)

§ A strong enhancement is observed near the mass threshold of MK at BES II. _ § Preliminary PWA with various combinations of possible N* and Λ* in the fits —— The structure Nx* has: Mass 1500~1650 Me. V consistent with N*(1535) properties Width 70~110 Me. V JP favors ½It has large BR(J/ψ p. NX*) BR(NX* KΛ) 2 X 10 -4 , suggesting: NX* has strong coupling to KΛ _ if N*(1535): strong coupling to KL and p would suggest significant ss content _ J/ p. KL and ’ p. K L analyses are important future research topics for BESIII _ _

baryonium in J/ pp? BESII 0 0. 1 0. 2 0. 3 Mpp-2 mp (Ge. V) BESII PRL 91 (2003) 022001 BESIII Chinese Physics C 34, 421 (2010)

Partial Wave Analysis of J/ pp BESIII ar. Xiv: 1112. 0942 PRL Include S-wave FSI November 26, 2011 Hai-Bo Li (IHEP) fixed to PDG

X(1835) and two new structures J/ + + + - X(1835) two new ones! consistent with 0 -+ f 1(1510) Bkg-subtracted; BESIII PRL 106, 072002 (2011) X(1835): same mass and Resonance X(1835) X(2120) X(2370) JPC X(1835) Eff. -corrected _ as the pp peak, but larger width M( Me. V/c 2) 1836. 5± 3. 0+5. 6 -2. 1 2122. 4± 6. 7+4. 7 -2. 7 2376. 3± 8. 7+3. 2 -4. 3 ( Me. V/c 2) Stat. Sig. 190. 1± 9. 0+38 -36 >20σ 83± 16+31 -11 narrow!! 7. 2σ 83± 17+44 -6 6. 4σ38

What are the new structures? way above threshold, but narrow!! PRD 73, 014516(2006) Y. Chen et al ü first resonant structures observed ----in the 2. 3 Ge. V region: -LQCD predicts that the lowest –lying -----pseudoscalar glueball: around 2. 3 Ge. V -J/ ’ + - is a good decay channel ----for finding 0 -+ glueballs. 0 -+: 2560(35)(120) 2++: 2390(30)(120) ü X(2120)/X(2370) possibilities: -pseudoscalar glueball ? - / excited states? PRD 82, 074026, 2010 J. F. Liu, G. J. Ding and M. L. Yan PRD 83: 114007, 2011 (J. S. Yu, Z. -F. Sun, X. Liu, Q. Zhao)

results on the hc & c charmonium states 0

c(1 S) • The S-wave spin-singlet charmonium ground state, found in 1980 • M & measurements: -J/ radiative transitions: - processes / B K c: M ~ 2978. 0 Me. V, ~ 10 Me. V M = 2983. 1± 1. 0 Me. V/, = 31. 3± 1. 9 Me. V • CLEOc found that the _ c line shape in ’ decays is distorted. gg, pp, B decay Mass (1 S, 2 S) g c C. L. =0. 0014 width C. L. <0. 0001

’ c , c exclusive decays BESIII Preliminary interference with non-resonant background is significant!! Ks. K K+K- 0 + - Ks. K 3 2 K 2 0 6 Relative phase f values from each mode are consistent within 3 s, use a common phase value in the simultaneous fit. M: 2984. 4 ± 0. 5 ± 0. 6 Me. V : 30. 5 ± 1. 0 ± 0. 9 Me. V : 2. 35 ± 0. 04 rad BESIII ar. Xiv: 1111: 0398 PRL

Summary of recent c results ‘ ‘ Hyperfine splitting: M(1 S) = 112. 5 ± 0. 8 Me. V Theorists are happier with this value (earlier result was too large for them)

hc 1 (P 1) • Spin singlet P wave (S=0, L=1) • Potential model: if non-zero P-wave spin-spin interaction, DMhf(1 P) = M(hc) - <m(1 3 PJ)> ≠ 0 where <m(1 3 PJ)>= [(M( c 0)+3 M( c 1)+5 M( c 2)]/9, • CLEOc observed hc in ee ’ 0 hc, hc c DMhf(1 P)=0. 08± 0. 12 Me. V/c 2 Consistent with 1 P hyperfine splitting = 0. Theoretical prediction: BF( (2 S) 0 hc) = (0. 4 -1. 3)× 10 -4 BF(hc c) =48% (NRQCD) BF(hc c) =88% (PQCD) Kuang, PR D 65 094024 (2002) BF(hc c) =38% Godfrey and Rosner, PR D 66 014012(2002) PRL 101 182003 (2008)

methods for studying the hc only detect the 0 “inclusive” (compute Mhc from kinematics) 0 hadrons detect the 0 & “E 1 -tagged” (compute Mhc from kinematics) detect the 0 , & all c Xi decay products “exclusive” (compute Mhc from 4 -C kinematic fit)

’ 0 hc , hc c BESIII: PRL 104 132002 (2010) Mass = 3525. 40± 0. 13± 0. 18 Me. V/c 2 Width = 0. 73± 0. 45± 0. 28 Me. V <1. 44 Me. V @90% E 1 tagged CLEOc: PRL 101 182003 (2008) Mass = 3525. 28± 0. 19± 0. 12 Me. V Width: fixed at 0. 9 Me. V Hyperfine mass splitting Mhf(11 P)= M(hc ) - <m(13 PJ )> inclusive BESIII: 0. 10± 0. 13± 0. 18 Me. V/c 2 CLEOc: 0. 02± 0. 19± 0. 13 Me. V/c 2 By combining inclusive results with E 1 -photon tagged results BF( ' 0 hc ) = (8. 4± 1. 3± 1. 0) × 10 -4 BF(hc c) = (54. 3± 6. 7± 5. 2)% Agrees with prediction from Kuang, Godfrey, Dude et al. 46

’ 0 hc, hc c , c exclusive decays BESIII Preliminary Summed distribution 832± 35 evts. 16 different c decay channels Simultaneous fit to 0 recoiling mass 2/d. o. f. = 32/46 Mass = 3525. 31 ± 0. 15 Me. V/c 2 Width = 0. 70 ± 0. 28 ± 0. 25 Me. V consistent with BESIII E 1 -tagged results

c lineshape from 0 hc, hc c Sum of 16 of C decay modes Background subtracted The C lineshape in hc C is not as distorted as in c decays; the non-resonant interfering bkg is small (non-existent? ). Ultimately, this channel will be best suited to determine c resonance parameters. yesterday’s search today’s discovery tomorrow’s calibration

New this week: 1 st observation of the b(2 S)

Background: B * B* threshold states ( ) B* B* BB

ϒ(4&5 S) “bottomonium” bb mesons ϒ(4 S) ϒ(5 S) _ 2 MB = 10358. 7 Me. V

“ (5 S)” is very different from other states Anomalous production of (n. S) + Belle PRL 100, 112001(2008) (Me. V) X 10 --2

(4 S) (1 S) + - 2 S 3 S 52± 10 evts 477 fb-1 (4 S) (1 S) + - 325± 20 evts! Belle: (4, 5 S) + - (1 S) 23. 6 fb-1 Belle: PRL 100 112001 4 S Belle: PRD 75 071103 ~1/20 th the data ~1/5 ththe cross-section

Look at + - recoil mass in (5 S) + -+ X X= (1 S) hb(1 P) (2 S) hb(2 P) (3 S) 121. 4 fb-1 MM( + -) spectrum hb(1, 2 P) JPC=1+1 st observations MM( + -) residuals Belle: PRL 108 032001

_ (bb) : S=0 L=1 JPC=1+- hb(1, 2 P) Expected mass (M b 0 + 3 M b 1 + 5 M b 2) / 9 MHF test of hyperfine interaction Deviations from Co. G of b. J masses hb(1 P) hb(2 P) (1. 6 1. 5) Me. V/c 2 (0. 5 +1. 6 ) Me. V/c 2 -1. 2 Agrees with expectations Previous search Ba. Bar 3. 0 (3 S) → 0 hb(1 P) ar. Xiv: 1102. 4565 MM( 0) Belle PRL 108, 122001 January

[ (5 S) hb(n. P) + - ] is large hb(1 P)~50, 000 evts hb(2 P)~85, 000 evts spin-flip = for hb(1 P) for hb(2 P) no spin-flip Process with spin-flip of heavy quark is not suppressed Mechanism of (5 S) hb(n. P) + - decay is exotic

Resonant structure of “ (5 S)” hb(n. P) + measure (5 S) hb yield in bins of MM( ) PHSP hc M(hb(1 P) +) M 1 = Me. V/c 2 M 2 = Me. V non-res. ~0 X _ ~BB* threshold _ ~B*B* threshold M(hb(2 P) +) Me. V/c 2 Me. V

Look at “Υ(5 S)” Υ(n. S) + Dalitz distributions for events in Y(n. S) signal regions. 9. 43 Ge. V <MM(π+π-) < 9. 48 Ge. V Υ(2 S)π+π- 10. 33 Ge. V <MM(π+π-) < 10. 38 Ge. V Υ(3 S)π+π- M 2(ϒπ±)max Υ(1 S)π+π- 10. 05 Ge. V <MM(π+π-) < 10. 10 Ge. V M 2(π+π-) To exclude contamination from gamma conversions we require: M 2(π+π-) > 0. 20 Ge. V 2 M 2(π+π-) > 0. 16 Ge. V 2 Belle PRL 108, 122001 M 2(π+π-) > 0. 10 Ge. V 2

Fit results: (1 S) + - (5 S) (2 S) + - M(Υ(1 S)π)max M(Υ(2 S)π)max (5 S) Zb 1 Zb 2 (5 S) (3 S) + - M(Υ(3 S)π)max M=10611 4 3 Me. V M=10609 2 3 Me. V M=10608 2 3 Me. V =22. 3 7. 7 4. 0 Me. V =24. 2 3. 1 3. 0 Me. V =17. 6 3. 0 Me. V M=10657 6 3 Me. V M=10651 2 3 Me. V M=10652 1 2 Me. V =16. 3 9. 8 6. 0 Me. V =13. 3 4. 0 Me. V =8. 4 2. 0 Me. V

2 m. B* m. B+m. B* Summary of parameter measurements Zb(10610) Zb(10650) M=10607. 2 2. 0 Me. V M=10652. 2 1. 5 Me. V =18. 4 2. 4 Me. V =11. 5 2. 2 Me. V Belle PRL 108, 122001 last month

_ _ B-B* & B*-B* molecules? ? Zb(106010)± B Zb(106050)± b B* b b _ _ _ B-B* “molecule” MZb(106010) –(MB+MB*) = + 3. 6 ± 1. 8 Me. V b _ _ B* B* _ B*-B* “molecule” MZb(106010) – 2 MB* = + 3. 1 ± 1. 8 Me. V Slightly unbound threshold resonances? ? Belle: PDG: M=10608. 1 1. 7 Me. V =15. 5 2. 4 Me. V MB + MB* = 10604. 5 0. 6 Me. V M=10653. 3 1. 5 Me. V =14. 0 2. 8 Me. V MB* + MB* = 10650. 2 1. 0 Me. V

On to observation of the b(2 S)

1 st: b(1 S) signals from hb(n. P) b(1 S) hb(1, 2 P) b(1 S) are expected to be prominent (20%~50%) hb b X Final state: + - X Bondar, Mizuk (Belle) Ar. Xiv 1110. 2251 hb(1 P) b(1 S) measure hb yields in bins of MM( + - ) (require 10. 59<MM( )<10. 67 Ge. V, i. e. =MZb 1, 2) “ϒ(5 S)” + -ϒ(2 S) “ϒ(5 S)” + -hb(1 P) hb(1 S) Belle Mhfs(1 S)=59. 3± 1. 9+2. 4 -1. 4 Me. V ry +1. 4 a M[ b(1 S)]=9401. 0± 1. 9 in -2. 4 Me. V +5. 5 +11. 5 m [ b(1 S)]=12. 4 -4. 6 -3. 4 Me. V eli (1 S)]=50 +13 r hb(2 P) b(1 S) Bf[hb(1 P) -9 % p b ϒ(2 S) MM( + -)

Comparisons: b(1 S) results PRL 101, 182003 (2008 ) Ba. Bar Bondar, Mizuk, et al (Belle)Ar. Xiv 1110. 2251 Belle hb(1 P) b(1 S) ϒ(3 S) b(1 S) PRD 81, 031104 (2010) CLEO hb(2 P) b(1 S) Expt DMhfs(1 S) (Me. V) Ba. Bar 66. 1 +4. 9 -4. 8 ± 2. 0 CLEO 68. 5± 6. 6± 2. 0 Belle 59. 3± 1. 9 +2. 4 -1. 4 NRQCD LQCD ϒ(3 S) b(1 S) Reasonable agreement among experiments and with theory

1 st observation of the b(2 S) hb(2 P) b(2 S) is expected to be the dominant decay mode (20%~50%) hb Final state: + - X b X New!!! Belle hb(2 P) b(2 S) measure hb(2 P) yields in bins of MM( + - ) (require 10. 59<MM( )<10, 67 Ge. V, i. e. =MZb 1, 2) +2. 8 Mhfs(2 S)=24. 3± 3. 5 y r -1. 9 Me. V ina +2. 8 m -1. 9 Me. V M[ b(2 S)]=9999. 0± 3. 5 eli r p b(2 S)]=47. 5± 10. 5+6. 6 Bf[hb(2 P) -7. 7 % MM( + - )

Was CLEO first? ? Yesterday! b(2 S)? b(1 S)?

ϒ(2 S) g b(2 S)? Comparison: b(2 S) “signals” Belle: IWHSS’ 12 April, 2012 Seth: Trento April 2012 Belle: hb(2 P) g b(2 S) CLEO Bf[hb(2 P) hb(2 S)] about right anomalously large production rate (~0. 2✕ b 1 rate) MM( + - ) Expt DMhfs (2 S) (Me. V) CLEO 48. 7± 2. 7 Belle 24. 3± 4. 3 ≈5σ discrepancy strong disagreement with theory agrees with theory

LQCD predictions for Mhfs(1, 2 S) Mhfs(1 S) Mhfs(2 S) Mhfs(1 S) Ba. Bar/CLEO Belle Meinel PRD 82, 114502 (2010) Mhfs(2 S) cc Belle HP-QCD PRD 85, 054509 (2012) m 2

BESIII c(2 S) (Ks. K+ - ) 106 M BESIII preliminary c(2 S) ’ M 1 E 1 c(2 S) ’ c(2 S) yield ≈ 0. 005 ’- c 1 yield BF( ’ c(2 S)) BESIII preliminary = (4. 7± 0. 9± 3. 0)× 10 -4 BF( ’ c 1)= 9. 2± 0. 4% Same M 1 vs E 1 suppression applies to bb PDG _

Summary _ §Clear evidence for the influence of the KK threshold on the a 0(980)-f 0(980) system _ §probably not pure KK molecules, but dynamical effects are strong §Curious suppression of ’ decay is observed § c 1 V (V= , , ) observed at a rate much larger than predictions §J/ + - 0 decays are dramatically different from ’ + - 0 decays §a new twist on an old puzzle _ § ’ pp is a nearly background-free source of N*(1535) _ §is there a substantial ss content in the N*(1535)? _ _ PC §The J of the pp mass-threshold enhancement J/ pp decays is 0 -+ § 2 new + - ’ resonances seen at 2120 Me. V and 2370 Me. V §widths are narrow ( ~80 Me. V) 2++ & 0 -+ glueballs? §Precision measurements of c and hc charmonium-state properties are made §interference with non-resonant bkg is significant §First observation of b(2 S) - Mhfs(2 S) = 24. 3± 4. 3 Me. V - no surprises Bf[hb(2 P) b(2 S)] = 47± 13% preliminary

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