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New Particles from Belle

New Particles from Belle. S. L. Olsen ( U. of Hawaii). GHP 2004 Fermilab, October, 2004. B-factory bonuses:. new insights/puzzles in charm/charmonium spectroscopy. B  K K s Kp. h c ’. B  K p + p - J/ y. X(3872). M(K s K p ). M( p + p - J/ y). e + e -  J/ y cc. B  K w J/ y.

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New Particles from Belle

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  1. New Particles from Belle S. L. Olsen (U. of Hawaii) GHP 2004 Fermilab, October, 2004

  2. B-factory bonuses: new insights/puzzles in charm/charmonium spectroscopy BK KsKp hc’ BKp+p-J/y X(3872) M(KsKp) M(p+p-J/y) e+e-J/y cc BKwJ/y ?? hc ‘ cc0 ?? hc J/y recoil mass M(wJ/y)

  3. bccs is a dominant process CKM favored J/y, y’, hc, cc1,… c Vcb c b W- Brs~10-2 (inclusive) cosqC s B mesons are a good source for charm charmonium and other cc states

  4. KEKBis a good source of Bs >900pb-1/day (~1M BBs/day) 1.2x1034/cm2/s

  5. Kinematic variables for the (4S) BK hc Ecm/2 KSKp e- e+ B B ϒ(4S) Ecm/2 DE CM energy difference: BK hc KSKp Beam-constrained mass: Mbc

  6. 1st Observation of the hc

  7. BK (KSK±pŦ)Mbc for 40 MeV M(KSKp) slices 3640 MeV BK hc’ 42fb-1 KSKp BK hc 3000 MeV KSKp

  8. Fit each bin … 3.55 GeV • Nevt = 45.3 ± 12.6 Mhc’ = 3653 ± 10 MeV • Ghc’ = 33 ± 22 MeV hc’: 3.60 GeV 3.65 GeV 3.70 GeV 3.75 GeV Mbc DE … • Nevt = 90.5 ± 14.9 Mhc = 2978 ± 5MeV • Ghc = 33 ± 16 MeV hc: M(KSKp)

  9. Subsequent measurementsconfirm higher mass value ggKSKp ggKSKp 3642 MeV BaBar (preliminary) CLEO hep-ex/0306060 e+e-J/yX 3630 MeV 3633 MeV elle hc hc ‘ Mx

  10. hc’: current status DM(1S) = MJ/y– Mhc = 117±1 MeVDM(2S) = 49 ± 4 MeV smaller Mavg =3637±4 MeV (Crystal Ball excluded)

  11. The X(3872) with 253 fb-1

  12. B±K±p+p-J/y (275M (4S)BB decays) Nev = 48.6 ± 7.8 M = 3872.4 ± 0.7 MeV (width consistent with resol) Mbc for 5 MeV M(ppJ/y) bins

  13. Now M(p+p-) is really r-like background estimated from Mbc-DE sidebands

  14. Confirmed by CDF & D0 CDF D0 X(3872) X(3872) PRL 93, 262001(2003) hep-ex/031202 hep-ex/0405004

  15. also seen by BaBar 3.5 σ effect hep-ex/0406022 M=3873.4 ± 1.4 MeV B(BKX)B(Xp+p-J/y) = (1.28± 0.24) x 10-5 Belle (1.3± 0.3) x 10-5

  16. X(3872) Mass D+D*- threshold (Plot from Soon Yun Jun’s FPCP04 CDF hot topics talk)

  17. Charmonium possibilities cc level spectrum hc” cc1’ y2 y3 hc’ 3872 MeV MD+ MD* hc2 y” hc’ 2MD y’ hc cc2 cc1 cc0 J/y hc

  18. p+p-J/ydecays violate isospin M too low; G too small angular dist’n rules out 1+- M too low; G(gJ/y) too small G(gcc1) too small; mpp wrong pp hc should dominate ppJ/y G( gcc2 & DD) too small; mpp wrong No obvious cc candidates for X(3872) hc” hc’ cc1’ y2 hc2 y3

  19. Look at BK p+p-p0 J/y

  20. BK w J/y wp+p-p0 M(J/yp+p-p0) BK X(3872); XJ/yp+p-p0? M(p+p-p0)

  21. 1: look at BK w J/yDalitz Plot Mbc cut here M2(J/yw) DE BK* J/y Kw Mp+p-p0 M2(Kw)

  22. Slice into 40 MeV-wide M(w J/y) bins Large deviation from phase-space Fit

  23. Slice into 40 MeV-wide M(w J/y) bins Adding a BW helps Fit M≈3940 ± 11 MeV G≈ 92 ± 24 MeV

  24. M(Kw) for the signal region 3880 <M(wJ/y)<3900 MeV No peaking In M(Kw) M(Kw) (GeV)

  25. Look back at the p+p-p0 masses Very clear w signal 28w’s 76w’s 20w’s 26w’s

  26. What is it? • Charmonium? • Conventional wisdom: wJ/y should not be a discovery mode for a cc state with mass above DD & DD* threshold! • Some kind of w-J/y threshold interaction? • the J/y is not surrounded by brown muck; can it act like an ordinary hadron? • cc-gluon hybrid? • Predicted by lattice QCD, including states with large hadron+cc widths, but the masses are predicted to be 4.3 ~ 4.4 GeV w J/y

  27. Evidence for X3872K p+p-p0 J/y

  28. M(p+p-p0J/y) vs M(p+p-p0) revisited M(J/yp+p-p0) look along here BK X(3872) J/yp+p-p0 M(p+p-p0)

  29. M(3p J/y) = MX(3872)± 16.5 MeV (±3 s) Look at 25 MeV-wide M(p+p-p0) mass bins DE Mbc

  30. B-meson yields vs M(p+p-p0) 12.4 ± 4.2 evts

  31. “Sidebands” BKwJ/y Non-resonant or “peaking bkgd sidebands Overlap region

  32. Cross-talk from BKwJ/y enhancement?  f dm = 0.75 ±0.14 evts Check : signal yield for M(3p J/y)= M X(3872) +1s/–3s (no overlap with w band) 12.4 evts  11.5 evts (expect 11.0 for no X-talk)

  33. Other sidebands(no significant signals) 4.3 ±6.2 evts Non-res bkd in signal bin = 1.3 ± 1.0 evts 6.4 ± 5.6 evts Area of I and III each = 4x Area of signal bin

  34. M(K3p) for signal bin

  35. Branching fraction 0.188 12.4 ± 4.2 Br(Xp+p-p0 J/y) Br(Xp+p-J/y) Nev(p+p-p0 J/y) e(2pJ/y) Nev(p+p-J/y)e(3pJ/y) = 62.6 ± 8.3 0.036 = 1.1 ± 0.4 (stat) ± 0.3 (syst) Accept:ance: 10% Xtalk/Bkgnd: -20% Xp+p-p0 J/y: +25% M(3p)<750 MeV significance ≈ 4s

  36. Consistent with sub-threshold X(3872)w* J/y • Mw + MJ/y = 3879 MeV (7 MeV above 3872) • Xw J/y occur via virtual w’s, 3p masses cluster at the kinematic limit. • G(Xp+p-p0J/y)/G(Xp+p- J/y) = 1.1±0.4 ± 0.3 • In agreement with Swanson’s DD* bound-state model for the X(3872)[PLB 588,189 (2004)] • Smoking gun for qqqq interpretation of X(3872)? - - -

  37. continuum e+e-J/y (cc) with 287 fb-1 Details in Tom Ziegler’s talk in session B3 Sunday, Snakepit 5:08PM

  38. 2002 2003 L=101 fb-1 L=155 fb-1 - • e+e-J/y (cc) > e+e-J/yglue • s(e+e-J/yhc) > 10x theory • evidence for hc’ • ggJ/y J/y negligible • confirm hc’ 2004 287 fb -1 ‘ hc hc cc0 non-zero continuum below DD threshold 4th peak!!

  39. What is the 4th peak? • the reconstruction and selection procedure is the same as before • Extend the fit region • no signal of X(3872) • significant (>4s) peak at M=3940  11 MeV • N=14833 (4.5) • the width is consistent w/ resolution (= 32 MeV) X(3872) hc ‘ hc ‘ cc0 hc What is it? cc0? hc ?? ‘ “

  40. Look at e+e-J/y D(D(*)) • Reconstruct a J/y & a D • use D0K-p+ & D+K-p+p+ • Determine recoil mass

  41. Look at M(DD(*)) 3940 MeV 9.9 ± 3.3 evts (4.5 s) DD* cc0DD* ‘ DD 4.1 ± 2.2 evts (2.1 s) hcDD “

  42. What is this one? • Is it too narrow to be the same as the wJ/y peak at 3940 MeV??? under investigation • We are looking for wJ/y recoiling from a J/y in the continuum • & BK “Y(3940)”; “Y(3940)”DD* • cc0 or hc most likely charmonium states • DD* signal rules against cc0 • Mass is a little low for hc • DM(3S) would be ≈ 100MeV • can DM(3S) > DM(2S)? ‘ “ ‘ “

  43. JP of the DsJ(2317) and DsJ(2457) from BDsJD decays Details in Alexey Drutskoy’s talk in session C1 Monday, 1-West 2:36PM

  44. DsJ(2317) and DsJ(2457) BaBar - DsJ(2317) CLEO DSJ(2317) DsJ(2317) Ds0 DSJ(2317) M(Ds0) DSJ(2457) DsJ(2317) Ds*0 M(Ds0) M(Ds*0) Masses are significantly lower than potential model P-level predictions - speculations about 4-quark, DK-molecule and Dsπ atom, csghybrid…

  45. B  D DsJ(2317) (and DsJ(2457)) J=1 J=1 DsJ(2317)Ds0 DsJ(2460)  Ds*0 J=0 J=2 DsJ(2460)D s  Belle DSJ(2317) DSJ(2317) DsJ(2317) Ds0 DsJ(2460) Ds  DSJ(2457) DSJ(2457) DSJ(2457) DsJ properties are consistent with two lowerst P-level states DsJ(2457) consistent with JP=1+DsJ(2317) consistent with 0+ No Ds0 decay  rules out 0+,1- Flat decay angle distribution Ds decay  rules out 0+,0- No Ds+ - and Ds decays Helicity in BDDsJ(2457) prefer J=1

  46. Summary • hc’ established DM(2S) < DM(1S) (as expected) • G(X(3872)p+p-p0J/y) ≈ G(X(3872) p+p-J/y) • good for molecules; bad for charmonium • Broad near-threshold wJ/y peak at 3940 MeV • too broad for charmonium • too light for cc-glue hybrid? • threshold interaction involving a J/y ? • Narrow(?) peak at 3940 in e+e- J/y X recoils • May be too narrow to be the wJ/y state seen in B decays • seen in DD* (rules out cc0’) • mass too low to be the hc” • DsJ consistent with Jp=0+ for DsJ(2317) • and Jp=1+ for DsJ(2457)

  47. Backup Slides

  48. Other results on the X(3872) - Look for X(3872)gcc2 (gcc2) • - J/y helicity angle dist inconsistent with JPC = 1+- •  rules out X=21P1 (hc’) Mbc Mgcc2 G(Xgcc2) G(Xp+p-J/y) <1.1 - Contrary to expectations for charmonium 3D3 c2=75/9 expect: dN dcosq J/y sin2q X |cosqJ/y|

  49. Other new results on the X(3872), cont’d BK g J/y BKcc1; cc1g J/y 90% CL upper limit: Br(Xg J/y) Br(Xp+p-J/y) <0.4 no X(3872) M(g J/y)-M(J/y) Probably not the cc1’

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