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Observation of Anomalous e + e -   ( nS ) h + h - Production at  ( 5S ) Energies

Observation of Anomalous e + e -   ( nS ) h + h - Production at  ( 5S ) Energies. November 8, 2007, HEP Seminar @ NTHU. Outline. Motivation  (4S),  (3S)   (1S) p + p - Template Dataset on  (5S) Event Selection for  (nS) h + h - Results Discussion Summary.

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Observation of Anomalous e + e -   ( nS ) h + h - Production at  ( 5S ) Energies

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  1. Observation of Anomalous e+e-(nS)h+h- Production at (5S) Energies November 8, 2007, HEP Seminar @ NTHU

  2. Outline • Motivation • (4S), (3S)  (1S)p+p- Template • Dataset on (5S) • Event Selection for (nS)h+h- • Results • Discussion • Summary All Results Preliminary arXiv:0710.2577 To be submitted soon to PRL

  3. Motivation

  4. 477 fb-1 ~ 1.7 x 10-5 expect limits only ... Motivation I: because it’s there Belle has ~ 20 fb-1(5S)data G≃ 110 MeV G≃ 20.5 MeV Gee≃ 0.13 keV Gee≃ 0.27 keV

  5. Motivation II: Enhancement? PRD 74, 017504 (2006)

  6. Motivation II: Enhancement? Conceived during FPCP2006 April ’06 in Vancouver PRD 74, 017504 (2006)

  7. Motivation of Motivation I sat through this SLAC Expt’l Seminar ...

  8. Motivation of Motivation 1-- Shuwei YE

  9. Motivation II: Enhancement? Y(4260)

  10. Note to myself ~ 7/13/05 Shuwei YE

  11. Shuwei YE

  12. Shuwei YE

  13. Motivation II: Enhancement?

  14. June 2005: Belle @ KEKB ~ 1.86 fb-1 • engineering run • June 9-31, 2006: Belle @ KEKB • ≅ 21.7 fb-1 Backdrop: Data on (5S) • 1985: CUSB, CLEO @ CESR ~ 116 pb-1 • 2003: CLEO III @ CESR ~ 0.42 fb-1

  15. (2S) (3S) (4S)(5S) Hint of events above background 1.86 fb-1 Rough study ~ 9/2006 (post summer) Took a year to analyze 21.7 fb-1, solely because of “computing”.

  16. (3S), (4S)  (1S)p+p- Template Old subject

  17. (3S)  (1S)p+p-Understanding (for (3S)  p+p-+ nothing) PRL 98, 132001 (2007) 2.9 fb-1 PRD 75, 072001 (2007) 1.14 fb-1

  18. Data from (3S) Run 528±24 3S 2S (3S)(2S)p+p- 1315±39 1S (3S)(1S)p+p- (2S)(1S)p+p- 4556±70 More can be done at Belle ...

  19. Data from (3S) Run (2S)(1S)p+p- (3S)(1S)p+p- Moxhay Model Brown-Cahn Model CLEO Model CLEO Model (3S)(2S)p+p- CLEO Model PRD 75, 072001 (2007) ☞ allow Ep1Ep2 term ! Brown-Cahn Model Much better data than CLEO CLEO Model

  20. 211 fb-1 (4S)  (1S)p+p- Template PRD 75, 071103(R) (2007) ~ 10-4 477 fb-1 2S 3S 4S PRL 96, 232001 (2006)

  21. Data on (4S) (2S)(1S)p+p- (3S)(1S)p+p- CLEO Model CLEO Model (4S)(1S)p+p- Brown-Cahn Model

  22. (3S), (4S)  (1S)p+p- Template Published papers by Belle, BaBar and CLEO So, (5S) straightforward.

  23. Dataset on (5S)

  24. 14 countries, 55 institutes, ~400 collaborators International Collaboration: Belle Seoul National U. Shinshu U. Sungkyunkwan U. U. of Sydney Tata Institute Toho U. Tohoku U. Tohuku Gakuin U. U. of Tokyo Tokyo Inst. of Tech. Tokyo Metropolitan U. Tokyo U. of Agri. and Tech. INFN Torino Toyama Nat’l College VPI Yonsei U. Nagoya U. Nara Women’s U. National Central U. National Taiwan U. National United U. Nihon Dental College Niigata U. Nova Gorica Osaka U. Osaka City U. Panjab U. Peking U. Princeton U. Riken Saga U. USTC BINP Chiba U. U. of Cincinnati Ewha Womans U. Fu-Jen Catholic U. U. of Giessen Gyeongsang Nat’l U. Hanyang U. U. of Hawaii Hiroshima Tech. IHEP, Beijing IHEP, Moscow IHEP, Vienna ITEP Kanagawa U. KEK Korea U. Krakow Inst. of Nucl. Phys. Kyoto U. Kyungpook Nat’l U. EPF Lausanne Jozef Stefan Inst. / U. of Ljubljana / U. of Maribor U. of Melbourne

  25. Belle detector Mt. Tsukuba Ares RF cavity KEKB Belle e+ source ~1 km in diameter The KEKB Collider SCC RF(HER) World record: L = 1.7118 x 1034/cm2/sec First successful op. of Crab cavities ARES(LER) 8 x 3.5 GeV 22 mrad crossing since 1999

  26. Belle Detector ACC (PID) Aerogel Cherenkov Counter n=1.015~1.030 SC Solenoid 1.5T 3.5 GeVe+ ECL CsI(Tl) 16X0 TOF 8 GeVe- CDC Central Drift Chamber small cell +He/C2H6 KLM m/KL detection 14/15 lyr. RPC+Fe SVD Si Vertex Detector 3(4) lyr. DSSD

  27. Dataset on (5S) Main Purpose e.g.

  28. Event Selection for (nS)h+h- h = p, K

  29. Event Selection for (nS)h+h- • Track Prompt: within 5 cm of IP in z (beam direction) 1 cm in transverse • m+m- + h+h-(+ X0 Muon ID; loose h = p, K No other charged tracks with pT > 100 MeV/c2 • |M(m+m-) - M((nS))|< 150 MeV/c2 (3s) (nS) candidate • cos < 0.95 • reject e’sfaking ’s Electron ID • h = K case Kaon ID Main bkg :m+m-  m+m-e+e-that mimic(1S)e+e-(conversions) Remark: Looser than (4S)  (1S) p+p- analysis Crosschecks w/ (4S) and (3S)

  30. e+e- (nS)h+h-at 10.87 GeV 21.7 fb-1 Signal box to optimize on background 3S 2S 1S m+m-g[→e+e-]

  31. Results

  32. 3S 4S (4S)  (1S) p+p- 4S 2S 2S 3S 3S 4S Expect to vanish “(5S)” (1S)p+p-, (2S)p+p- (2S)p+p- 3S “(5S)” 2S 1S Striking ! (1S)p+p- “(5S)” >

  33. “(5S)” some other reflection ? 4S 2S 3S Remarks e+e- (1S)p+p- > • Structure at ~ 0.84 GeV/c2 below 3S: “(5S)” → (2S)p+p- ↳(1S) + X0 • “(5S)”: single ECM energy at 10.87 GeV No clear indication of radiative tail

  34. 14s 20s (3S)p+p- “(5S)” (nS)p+p-, (1S)K+K- 3.2s Signal box to optimize on background (2S)p+p- (1S)p+p- square box gives ~ 3.9s (1S)K+K- 4.9s

  35. (2S)p+p- (3S)p+p- (1S)K+K- (1S)p+p- 20s 14s Yield: Unbinned extended ML Fit bkg yield signal yield bkg PDF [linear ⇐ optimze box signal PDF [two Gaussians 3.2s 4.9s

  36. (1S)p+p- (2S)p+p- cosqHel CLEO’07 Efficiency estimate: re-weighted MC according to data M(pp) and cosqHel Distributions phase space Brown-Cahn Model N.B. other two modes use B-C model due to limited statistics

  37. Systematic Uncertainty Source (1S)p+p-(2S)p+p- (3S)p+p- (1S)K+K- Tracking 4.1% 4.6% 5.6% 4.1% Lepton Ident. 1.0% 1.0% 1.0% 1.0% Electron rejection 0.2% 0.2% 0.4% 3.6% Fitting 1.5% 3.7% 1.7% 1.4% pp model 4.4% 6.8% 3.2% 13.6% M(mmpp) selection 2.6% 2.6% 2.6% 2.6% Bhabha rejection 1.9% 1.9% 1.9% 1.9% Trigger 0.9% 3.1% 4.5% 1.0% Luminosity 1.4% 1.4% 1.4% 1.4% Cross-section 5.0% 5.0% 5.0% 5.0% (nS) →mm bf 2.0% 8.8% 9.6% 2.0% Total 9.0% 14.4% 14.0% 16.1%

  38. Echoes Y(4260) Need Mechanism Need Scan to tell Summary Table Assume “(5S)” = (5S) PDG value taken for (nS) properties N.B. Resonance cross section 0.302 ± 0.015 nb at 10.87 GeV PRD 98, 052001(2007) [Belle] Cf (2S)  (1S)p+p- ~ 6 keV (3S) 0.9 keV (4S)1.8 keV • Is this (5S), or the Yb state? N.B. G(5S)  e+e- ≃ 0.13 keVnormal

  39. Discussion

  40. 10.75 10.8 10.85 10.9 10.95 11.0 Scan ? ~ 8 fb-1 PRL 98, 052001 (2007) 6/2005 “scan” 5 points, 30 pb-1 each (stat error) fit with G= 110 MeV Yb!? Compare (1S)p+p-,(2S)p+p- vs Hadrons

  41. No Indication ! Certainly “Anomalous” !

  42. More Y’s from BaBar and Belle Y(4320)

  43. Two Y’s ? Y(4360)=Y(4320) ? Y(4660) !

  44. 10.75 10.8 10.85 10.9 10.95 11.0 Scan could uncover richer structure ! Scan ? ~ 8 fb-1 PRL 98, 052001 (2007) 6/2005 “scan” 5 points, 30 pb-1 each (stat error) fit with G= 110 MeV Yb!? Compare (1S)p+p-,(2S)p+p- vs Hadrons

  45. New preliminaryResult: 112 fb-1 • Based on new data skim (112 fb-1) w/ 4x efficiency • Now consistent w/ BaBar Revised publication coming soon Corrected (4S)  (1S)p+p- 477 fb-1 Uncover from this study - Data and signal yield correct - Efficiency estimate for signal normalization was wrong

  46. Summary arXiv:0710.2577 • Observation of“(5S)” (1S)p+p-,(2S)p+p- • Evidence for“(5S)” (3S)p+p-,(1S)K+K- • Assuming (5S) properties, • B((5S) (1S)p+p-) = • B((5S) (2S)p+p-) = • B((5S) (3S)p+p-) = • B((5S) (1S)K+K-) = • w/ partial widths 0.52 – 0.85 MeV⇐ Very Large • New preliminary Bf for (4S)  (1S)p+p- Cf. ~ 0.018 MeV for (4S) (1S)p+p-

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