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Belle

Belle. Hawaii activities in Belle New particles in BES & Belle S. L. Olsen. Belle highlights 2002-03. 1 st measurement of f 2 from B  p + p - 1 st observation of BK* l + l - Discovery of a new charmonium state 1 st measurement of f 3 (BKD 0 Dalitz plot)

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Belle

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  1. Belle Hawaii activities in Belle New particles in BES & Belle S. L. Olsen

  2. Belle highlights 2002-03 • 1st measurement of f2 from Bp+p- • 1st observation of BK*l+l- • Discovery of a new charmonium state • 1st measurement of f3 (BKD0 Dalitz plot) • Hint of new physics in BfKS • Measurement of Br(Bp0p0) • 1st radiative charm decay Dfg • … SM Belle has submitted/published 70 papers (30 since August 2002)

  3. Papers primarily from Hawaii group • New charmonium state • (hep-ex/0309032) S.-K. Choi, S.L. Olsen et al., • BDCP K • (hep-ex/0304032) S.K. Swain, T.E. Browder et al., (accepted by PRD) • BB mixing with BD*p (partial recon) • PRD 67 092004 (2003) Y.H. Zheng, T.E. Browder et al., • BhcK* 1st observation • PRL 90, 071801 (2003) F. Fang, et al., • Bhh • PRD 66, 092002 (2002) B.C.K. Casey, et al., • hc’ discovery • PRL 89, 102001 (2002) S.-K. Choi, S.L. Olsen, et al., • BppK 1st observation (PRL --- F. Fang) • ACP for Bh+h- (PRD --- B. Casey) • B-K1(1270) J/y (PRL --- S.-K. Choi, S.L. Olsen))

  4. Hawaii service in Belle • TOF system (essential for all CPV studies) • Calibration: Mike Jones • Reconstruction: Mike Peters • Tracking (essential to all analyses) • Kalman filter (fitting): Karim Trabelsi • KSp+p- selection: Fang Fang • Trigger • Level 0: Hulya Guler • Level 1.5 (SVD-CDC matching): Kirika Uchida • Background simulations (for SVD upgrade) • Spent particles: Karim Trabelsi • Synchrotron radiation: Sanjay Swain • MC • generator tuning: Rolf Seuster • Event generation: Eric Dodson

  5. Hawaii service in Belle (cont’d) • Utilities • Run-by-run CM energy calibration: Sanjay Swain • N(BB) determination: Sanjay Swain • General event selection criteria: Brendan Casey • SVD upgrade • Electronics: Gary Varner • Opto-Mechanical: Marc Rosen • Software: Karim Trabelsi & Kirika Uchida • Upgrades • DAQ: Gary Varner & Yang Heng Zheng • Pixels: Fang Fang • Administrative • Analysis coordinator: Tom Browder • Co-spokesperson: S. Olsen

  6. Other analyses underway • CPV in BD*r (Trabelsi & Peters) • CPV in Bhc KS (Fang) • CPV in BDCPK (Swain, Kent) • Charm fragmentation (Seuster) • BKpp J/y & B Kppy’ (Guler) • Search for 1hc1 (i.e. 1Pc1 cc state) (Fang) • Bh’(980)X (Uchida) • New particle searches (Olsen) • …

  7. New particles in Belle & BES • New state in BK p+p-J/y • MppJ/y = 3872 MeV (= MD + MD*) • inconsistent with a cc state • Low mass pp enhancement in • J/yg pp (BES) • B pp h (Belle) J/pp ??? BKpp ??? m(pp)

  8. New state in BK p+p-J/y

  9. These are narrow if M<MD+MD* charmonium levels DD* threshold 1Dc2 y”(3Dc1) m=? 3Dc3 3Dc2 DD threshold y’ ‘ 1h1? hc we found this last year in BK KsKp hc’ cc0,1,2 J/y hc cc level diagram:

  10. BK KSKp (hc’ studies) Mbc for 40 MeV KSKp mass bins what is this?? ?Dc2ggg? hc ‘ region veto hc

  11. Look for it in BK p+p-J/y(less background, better resolution)& BK gcc1 • 3Dc2pp J/y & g cc1  allowed • G(g cc1 ) > ~5 G(pp J/y) • 1Dc2pp J/y & g cc1  not allowed

  12. M(p+p-l+l-) –M(l+l-) y’ppJ/y ?

  13. Mbc for 10 MeV M(ppJ/y) bins XppJ/y signal!! y’ppJ/y

  14. Magnify signal region

  15. DE plots shows similar signal XppJ/y signal

  16. 3-d unbinned fit to y’ region (BK y’  K ppJ/y) Ny’ = 489 ± 23 events DE Mbc MppJ/y • DE=-1.96 ± 0.4 • s(DE)=11.6 ± 0.4 • f_tail = 3.6 ± 1.5% • Mbc=5279.1 ± 0.1 • s(Mbc)=2.6 ± 0.1 • MppJ/y=3685.5 ± 0.2 • s(Mppj/y)=3.3 ± 0.2

  17. 3-d unbinned fit to X(3872) region NX = 35.7 ± 6.8 events MppJ/y DE Mbc • DE=-1.96 (fixed) • s(DE)=11.6 (fixed) • f_tail = 3.6 % (fixed) • Mbc=5279.1 (fixed) • s(Mbc)=2.6 (fixed) • MppJ/y=3871.5 ± 0.5 • s(Mppj/y)=2.5 ± 0.5

  18. reference mass to y’ MX= Mmeas(ppJ/y) – Mmeas(y’) + MPDG(y’) MX = 3872 ± 0.6 (stat) ± 0.5 (syst) MeV This comes from comparing Mmeas(y’) with PDG value BW fit: G = 1.4 ± 0.7 MeV < 2.3 MeV @ 90% CL

  19. M p+p-tends to peak near limit background estimated from Mbc-DE sidebands

  20. rpp + bkgd fits pretty well

  21. Look for X(3872)gcc1 (cc1 g J/y) an allowed E1 transition; should be > 5 XppJ/y (Eichten, Lane & Quigg) • Select: B-K-g g J/y: • K- and J/y same as before • Eg>40 MeV plus p0 veto • 15 < M gJ/y-Mcc1<10MeV

  22. Do 2-d (Mbc and Mgcc1) fits y’ region Nevts = 34.1 ± 6.9 ± 4.1 events expect 26 ± 4 events (y’gcc1 gJ/y) Mgcc1 Mbc

  23. Mbc and Mgcc1 fits to X(3872) region No signal !! Mbc Mgcc1 NX = 3.7 ± 3.7 ± 2.2 events (<9.2 events @ 90% CL)

  24. Limit on G(Xgcc1): G(Xgcc1)/ G(XppJ/y) = 0.35 ± 0.36 ± 0.21 < 0.89 @ 90% CL

  25. Summary • we see a ~10s signal for B K X where: • X p+p-J/y, • MX= 3872.0 ± 0.6 ± 0.5 MeV; G<2.3 MeV(90%CL) • G(Xgcc1)/G(X p+p-J/y) < 0.89 (90%CL) • hep-ex/0309032  PRL • is this the 3D2 cc charmonium state? • Mass is too high (3872 vs 3810 MeV) • G(Xgcc1)/G(X p+p-J/y) too small (<0.89 vs > 5) • angular analysis is necessary (but hard). • MX~ MD0 + M D0*. =3871.3 ± 1.0 MeV • could it be a D-D* bound state?

  26. Low mass pp enhancement in J/yg pp (BES)

  27. Use BESII’s 58M J/y decays Select J/ygpp • 4-C kinematic fit • dE/dx for proton id • non-pp bkg small • main bkg from J/yp0pp J/ygpp ???? • J/yghc ; hcpp • (calibration reaction)

  28. Study J/yp0pp bkg with MC & data J/yp0pp (data) three-body phase space Monte Carlo J/yp0ppgpp (MC) M(pp)-2mp (GeV)

  29. The signal is real • Really protons and antiprotons • dE/dx pid verified by BSC response • Not bkgd from J/y hadrons • No hint of peaking in J/y p0 pp data • Not a QED background • Eg pulls are symmetric • cosqg distribution not peaked • not seen in off-J/y data

  30. Fit to data fitted peak location J/ygpp acceptance weighted BW M=1859 ± 3 +5-25 MeV G < 30 MeV (90% CL) c2/dof=56/56 0 0.1 0.2 0.3 M(pp)-2mp (GeV) 3-body phase space acceptance

  31. Is Mpeak really less than 2mp? weight events by q0/q: (i.e remove threshold factor) No turnover at threshold peak mass must be <2mp M(pp)-2mp (GeV)

  32. OK!! P-wave fit?? M=1876 ± 3 +?-?? MeV G < 30 MeV (90% CL) M=2mp!! c2/dof=59/56

  33. NG!! D-wave fit?? M=1885 ± ? +?-?? MeV G < 30 MeV (90% CL) c2/dof=1405/56

  34. cosqg distribution 1+cos2qg (expected for J/yg0-+) M(pp)<1.9 GeV sin2qg

  35. include possible biases as (asymmetric) systematic errors (at least for now) M=1859 ± 3 +5-25 MeV G < 30 MeV (90% CL)

  36. Summary • A large enhancement seen near 2mp in the Mpp distribution for J/ygpp decays. • Not apparent in J/ypopp decays • Not consistent with any PDG meson state • If it is an S-wave resonance: • Mpeak is below 2mp (M=1859 ±3 +5–25 MeV) • full width is narrow (G<30 MeV) • dN/dcosqg consistent with JPC = 0-+ • PRL 91, 022001 (2003)

  37. Comments • peak near but below 2mp : a pp bound state? • narrow width: why solong-lived? • similar patterns seen in baryon-antibaryon systems produced in B meson decays • BppK BppD BpLp BpLcp

  38. Belle sees low-mass pp systems in B decays Bppp BppK F. Fang M M pp pp BppK* BppKS M M pp pp

  39. low-mass pp peaks in all (?) Bbaryon decays BD0pp M pp

  40. Strange & charmed systems B-pLcp- B0pLp- M(Lp)(GeV) (in these cases, the peaking doesn’t seem to be right at threshold) M(Lc+p)(GeV)

  41. hh bound states (hadronium)?? There is lots & lots of literature about this possibility deuteron: hadronium: attractive nuclear force attractive force?? + n h p h p loosely bound 3-q color singlets with Md = 2mp-e loosely bound 3-q or q-q color singlets with Mb = 2mp-d

  42. hadronic moleculesa new spectroscopy?

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