1 / 27

Recent Bottomonium Results from BaBar

Recent Bottomonium Results from BaBar. Bryan Fulsom SLAC National Accelerator Laboratory 35 th International Conference on High Energy Physics Paris, France July 22, 2010. Overview. This talk:  (1D J )  p + p -  (1S)  (nS)  g (e + e - ) h b (1S)  (3S)  p + p - h b (1P)

jess
Download Presentation

Recent Bottomonium Results from BaBar

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Recent Bottomonium Resultsfrom BaBar Bryan Fulsom SLAC National Accelerator Laboratory 35th International Conference on High Energy Physics Paris, France July 22, 2010

  2. Overview • This talk: • (1DJ)  p+p-(1S) • (nS)  g(e+e-)hb(1S) • (3S)  p+p- hb(1P) • (3S)  po hb(1P)  g hb(1S) • BaBar: 1999-2008 • 122M (3S) / 100M (2S) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 2/22

  3. Overview • This talk: • (1DJ)  p+p-(1S) • (nS)  g(e+e-)hb(1S) • (3S)  p+p- hb(1P) • (3S)  po hb(1P)  g hb(1S) • BaBar: 1999-2008 • 122M (3S) / 100M (2S) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 2/22

  4. Overview • This talk: • (1DJ)  p+p-(1S) • (nS)  g(e+e-)hb(1S) • (3S)  p+p- hb(1P) • (3S)  po hb(1P)  g hb(1S) • BaBar: 1999-2008 • 122M (3S) / 100M (2S) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 2/22

  5. Overview • This talk: • (1DJ)  p+p-(1S) • (nS)  g(e+e-)hb(1S) • (3S)  p+p- hb(1P) • (3S)  pohb(1P)  g hb(1S) • BaBar: 1999-2008 • 122M (3S) / 100M (2S) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 2/22

  6. Overview • This talk: • (1DJ)  p+p-(1S) • (nS)  g(e+e-)hb(1S) • (3S)  p+p- hb(1P) • (3S)  po hb(1P)  g hb(1S) • BaBar: 1999-2008 • 122M (3S) / 100M (2S) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 2/22

  7. (1DJ) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 3/22

  8. (1DJ): General Information • Expected (1DJ=1,2,3) properties • m(1DJ) ~10160 MeV/c2, m(1DDJ) ~5-12 MeV/c2, G(1DJ) ~30 keV • Experimental observation • (3S)  gg(1D2?)  gggg(1S)  ggggl+l- • B((3S)  ggggl+l-) = (2.5 ± 0.5 ± 0.5)  10-5 • m(1D2?) = 10161.1 ± 0.6 ± 1.6 MeV/c2 • No evidence for (1DJ)  p+p-(1S) • Limit: B((1DJ)  p+p-(1S)) < 4% • Theory: Kuang & Yan ~40%, Ko ~2%, Moxhay ~0.25% Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 4/22

  9. (1DJ): BaBar Analysis • Reconstruct (3S)  gg(1DJ)  ggp+p-(1S)  ggp+p-l+l- • Require exactly 4 tracks • ml+l- consistent with / constrained to m(1S) • Minimize Egc2 to select best candidate • m(1DJ) resolution ~ 3 MeV/c2 • Maximum Likelihood fit to mp+p-l+l- spectrum • (1DJ) signals: Double Gaussian + Crystal Ball • Monte Carlo (MC)-determined backgrounds: • (3S)  gcbJ(2P)  gw (p+p- or p+p-po) (1S) • (3S)  p+p-(1S) + gFSR • (3S)  h (p+p-po) (1S) • (3S)  gg/popo (2S) (p+p-(1S)) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 5/22

  10. (1DJ): Fit Results m(1D2) = 10164.5 ± 0.8 ± 0.6 MeV/c2 Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 6/22

  11. (1DJ): Quantum Numbers • L: p+p- invariant mass • P(c2) for mp+p- distribution • D(84.6%), S(3.1%), P(0.3%) • J: pHelicity Angle • dN/d(cosqp) ~ 1 + x(3cos2qp-1)/2 •  = -1.0±0.4±0.1 consistent w. J = 2 • JP: Angle between p+p- and l+l- planes • dN/dc ~ 1 + bcos(2c), sign(b) = (-1)JP •  = -0.4±0.3±0.1 consistent w. JP = 2- Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 7/22

  12. hb(1S) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 8/22

  13. hb(1S): General Information • hb(1S) observed in inclusive g spectrum for (3S) and (2S) • Measured properties • B((3,2S)  ghb(1S)) = (5.1 ± 0.7)  10-4 / (3.9 ± 1.5)  10-4 • mhb(1S) = 9390.9 ± 2.8 MeV/c2, Ghb(1S) 10 MeV • (m(1S) – mhb(1S)) = 69.3 ± 2.8 MeV/c2 • Hyperfine splitting theoretical predictions • Lattice: ~50-60 MeV/c2 NRQCD: ~40 MeV/c2 Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 9/22

  14. hb(1S): Converted Photon Analysis • Converted photons (g  e+e-) improve resolution (25  5 MeV) • Fit pair of tracks, selected with c2fitter, mg, rg • Additional cuts: |cosqthrust|, Ntracks, poveto • Simultaneous fit to Eg* spectrum in (3S) and (2S) datasets • (3,2S)  ghb(1S): Breit-Wigner  Crystal Ball • e+e-E=m(nS)  gISR(1S): Crystal Ball • bJ(2,1P)  g(1S): Doppler broadening  Crystal Ball • Background: 4th order polynomial  exponential decay Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 10/22

  15. hb(1S): Fit Results Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 11/22

  16. g  e+e-: Results Summary • Eg* and branching fractions as expected • Mass-constrained fit: • No evidence for hb (2.3s stat.) • Best fit result in mhb(1S) region: • Differs by +12.4+3.8-4.0 MeV/c2 (3.3s stat., 2.6s w. syst.) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 12/22

  17. hb(1P) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 13/22

  18. hb(1P): General Information • Expect mhb(1P) = (mcb0(1P)+3mcb1(1P)+5mcb2(1P)) / 9  9900 MeV/c2 • Production mechanisms • B((3S)  p+p- hb(1P)) ~ 10-3 – 10-2 • B((3S)  po hb(1P)) ~ 10-3 • R(pohb (1P) / p+p-hb (1P)) = 0.05 – 20 • Expected decays • hb(1P)  ggg (57%), ghb(1S) (41%), ggg (2%) • Previous searches • B((3S)  p+p- hb(1P)) < 1.8  10-3 • B((3S)  po hb(1P)) < 2.8  10-3 Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 14/22

  19. p+p-hb(1P): Analysis Strategy • Reconstruct pair of oppositely charged tracks • Cuts on Etotal, R2, Ntracks, KSo veto (flight length, cos a) • Define p+p- recoil mass: mR2 = (m(3S) – E*p+p-)2 – P*p+p-2 • 2 fit to mR with 7 components • hb signal: Symmetric two-sided Crystal Ball (TCB) • (3S)  p+p- (2S): Asymmetric TCB + Bifurcated Gaussian • (2S)  p+p- (1S): same, with fixed feed-down components • b1,2(2P)  p+p- b1,2(1P): TCB, with fixed peak position • KSo  p+p-: MC-determined phase space • Non-peaking background: 6th order Chebychev polynomial Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 15/22

  20. p+p-hb(1P): Fit Results Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 16/22

  21. p+p-hb(1P): Fit Results Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 17/22

  22. p+p-hb(1P): Fit Results • No evidence for hb signal at mhb = 9900 MeV/c2 • B((3S)  p+p- hb(1P)) = (0.0 ± 0.5 ± 0.3)10-4 (<110-4 UL) • Most significant scan point <2s significance • Exclude B((3S)p+p-hb(1P)) > 2.510-4 (90% CL) over range Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 18/22

  23. pohb(1P): Analysis Strategy • Reconstruct po(g1g2) + g • Require Eg consistent with hb(1P)  ghb(1S) • Cuts on Ntracks, R2, po veto (all g candidates), po cosqh • Define po missing mass: m.m.(po)2 = (m(3S) – E*po)2 – P*po2 • Constrain mpo to improve resolution • Npo from mg1g2 fit in each m.m.(po) bin • 2 fit of m.m.(po) distribution • hb(1P) signal: Double Crystal Ball • Background: 6th order polynomial, from reweighted MC Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 19/22

  24. pohb(1P): Fit Results Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 20/22

  25. pohb(1P): Fit Results • Fixed mass fit: • B((3S)pohb(1P)poghb(1S)) = (3.1±1.1±0.4)10-4 (2.7s) • 1.510-4 < B((3S)pohb(1P)poghb(1S)) < 4.910-4 • Best fit mhb = 9903 ± 4 ± 1 MeV/c2 consistent with predictions • Combined results: • R(pohb(1P) / p+p-hb(1P)) > 3.2 (>1.5 for mhb = 9903 MeV/c2) Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 21/22

  26. Summary • (1DJ)  p+p-(1S) • First observation of (1DJ) hadronic decays • Quantum numbers and precise m(1D2) measurement • (2,3S) converted photon spectrum • Most significant (2.6s) “hb” signal at 9403.3±2.4+0.9-1.5 MeV/c2 • Improved and first direct cbJ(1,2P)  g (1S) measurement • hb(1P) Search • No evidence for (3S)  p+p- hb(1P) • Marginal evidence (2.7s) for (3S)  pohb(1P)  poghb(1S) • B((3S)pohb(1P)) / B((3S)p+p-hb(1P)) > 1 at 90% C.L. Recent Bottomonium Results from BaBar / Bryan Fulsom / ICHEP / 2010.07.22 / Page 22/22

  27. FIN

More Related