New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Observation of Anomalous e + e (nS) h + h Production at (5S) Energies November 15, 2007, SLAC Experimental Seminar
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Outline Motivation (4S), (3S) (1S) + Template Dataset on (5S) Event Selection for (nS) h + h Results Discussion Summary Preliminary All Results Preliminary arXiv: To be submitted soon to PRL
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation I: because it’s there ee ≃ 0.27 keV ee ≃ 0.13 keV ≃ 110 MeV ≃ 20.5 MeV Belle has ~ 20 fb 1 (5S) data expect limits only... ~ 1.7 x 10 fb 1
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation II: Enhancement? PRD 74, (2006)
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation II: Enhancement? PRD 74, (2006) Conceived during FPCP2006 April ’06 in Vancouver
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation of Motivation I sat through this SLAC Expt’l Seminar...
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation of Motivation Shuwei YE
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation II: Enhancement? Y(4260)
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Shuwei YE Note to myself ~ 7/13/05
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Shuwei YE
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Shuwei YE [cs][cs]-bar 4-quark state
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ lattice Mass: Use QQg hybrid (CLEO favored) lattice work to illustrate MeV (Michael) Could scale down, ∵ ccg prediction typically higher than Y(4260) Could show up in ISR on (5S) ➯ Could show up in ISR on (5S) – MeV (Juge, Kuti, Morningstar) Predicted ccg state ~ 4260 Prefers Higher Energy Scan ➯ Prefers Higher Energy Scan Width: 100 MeV (~ Y c = Y(4260)) plausible Product BR: Assume ~ Could be smaller or larger Guestimates BaBar/CLEO ─ ─ ─ 10865
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ hep-ph/ nucl-th/
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Motivation II: Enhancement?
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Backdrop: Data on (5S) 1985: CUSB, CESR ~ 116 pb 2003: CLEO CESR ~ 0.42 fb 1 June 2005: KEKB ~ 1.86 fb 1 engineering run June 9-31, 2006: KEKB ≅ 21.7 fb 1
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ solely because of “computing” fb 1 (2S) (3S) (4S) (5S) Rough study ~ 9/2006 (post summer) Hint of events above background Took a year to analyze 21.7 fb 1,
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ (3S), (4S) (1S) + Template Not a new subject
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ (3S) (1S) + Understanding 2.9 fb fb 1 75 PRD 75, (2007) (for (3S) + + nothing) 98 PRL 98, (2007 ) DM ( (1S))
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ (3S) (1S) (2S) (1S) (3S) (2S) 3S 2S 1S More can be done at Belle ± ± ± 70 Data from (3S) Run
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ (2S) (1S) (3S) (1S) (3S) (2S) Brown-Cahn Model CLEO Model 75 PRD 75, (2007) ☞ allow E E term ! Brown-Cahn Model Moxhay Model Much better data than CLEO CLEO Model Data from (3S) Run
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ (4S) (1S) + Template 2S 3S 4S 477 fb fb 1 75 PRD 75, (R) (2007) 96 PRL 96, (2006 ) ~ 10 4
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ (2S) (1S) (3S) (1S) (4S) (1S) CLEO Model Brown-Cahn Model Data on (4S)
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ (3S), (4S) (1S) + Template Published papers by Belle, BaBar and CLEO So, (5S) straightforward.
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Dataset on (5S)
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ countries, 55 institutes, ~400 collaborators 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 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 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 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. International Collaboration: Belle
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ e + source Ares RF cavity Belle detector World record: L = x /cm 2 /sec SCC RF(HER) ARES(LER) 8 x 3.5 GeV 22 mrad crossing ~ 1 km in diameter Mt. Tsukuba KEKB Belle since 1999 First successful op. of Crab cavities The KEKB Collider
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ / K L detection 14/15 lyr. RPC+Fe Central Drift Chamber small cell +He/C 2 H 6 CsI(Tl) Aerogel Cherenkov Counter n=1.015~1.030 Si Vertex Detector 3(4) lyr. DSSD TOF SC Solenoid 1.5T 8 GeV e 3.5 GeV e 16X ACC (PID) ECL SVD KLM CDC Belle Detector
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Dataset on (5S) Main Purpose: B s Physics e.g. 7 Will be submitted soon.
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Event Selection for (nS) h + h h = , K
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Event Selection for (nS) h + h Track Prompt: within 5 cm of IP in z (beam direction) 1 cm in transverse h h X 0 Muon ID;loose h = , K No other charged tracks with p T > 100 MeV/c 2 |M( - M( (nS))| < 150 MeV/c 2 (3 ) (nS) candidate cos < 0.95 reject e ’s faking ’s Electron ID h = K case Kaon ID Main bkg : + + e + e that mimic (1S)e + e Main bkg : + + e + e that mimic (1S)e + e (conversions) Remark: Looser than (4S) (1S) + analysis Crosschecks w/ (4S) and (3S)
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ [→ ee[→ ee 3S 2S 1S 21.7 fb 1 e + e (nS) h + h at GeV Signal box to optimize on background
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ fb 1 Corrected (4S) (1S) + Uncover from this study - Data and signal yield correct - Efficiency estimate for signal normalization was wrong 112 fb New preliminary Result: newskim Based on new data skim (112 fb ) w/ 4x efficiency Now consistent w/ BaBar Revised publication coming soon Note improved background shape
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Results
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ S 3S 4S 2S 3S 4S (4S) (1S) + Expect to vanish “ (5S)” (1S) + , (2S) + (2S) + 3S 4S > “ (5S)” (1S) + Striking ! 1S 2S 3S
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Remarks Structure at ~ 0.84 GeV/c 2 below 3S: “ (5S)” → (2S) + ↳ (1S) + X “ (5S)” “ (5S)” : single E CM energy at GeV No clear indication of radiative tail 2S 3S 4S e + e (1S) + > “ (5S)” some other reflection ?
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ “ (5S)” (nS) + , (1S) K + K (1S) + (2S) + (3S) + 3.2 14 20 Signal box to optimize on background (1S) K + K square box gives ~ 3.9 4.9 Kaon ID
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Yield: Unbinned extended ML Fit signal yield bkg yield signal PDF [two Gaussians bkg PDF [linear ⇐ optimize box 20 14 4.9 3.2 (1S) + (2S) + (1S) K + K (3S) +
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Brown-Cahn Model phase space M( ) and cos Hel Distributions (1S) + (2S) + Efficiency estimate: re-weighted MC according to data N.B. other two modes use B-C model due to limited statistics cos Hel CLEO’07
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Systematic Uncertainty Source Source (1S) + (2S) + (3S) + (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% model 4.4% 6.8% 3.2% 13.6% M( ) 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) → bf 2.0% 8.8% 9.6% 2.0% Total 9.0% 14.4% 14.0% 16.1%
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Summary Table N.B. Resonance cross section ± nb at GeV PRD 98, (2007) [Belle] Cf (2S) (1S) ~ 6 keV (3S) 0.9 keV (4S) 1.8 keV Echoes Y(4260) Need Mechanism Is this (5S), or the Y b state? Assume “ (5S)” = (5S) PDG value taken for (nS) properties Need Scan to tell N.B. (5S) e e ≃ 0.13 keV normal
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Discussion
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ No Indication ! Certainly “Anomalous” !
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Scan ? PRL 98, (2007 ) 6/2005 “scan” 5 points, 30 pb each (stat error) fit with 5S = 110 MeV ~ 8 fb (1 fb pts) Compare Hadrons vs (1S) + , (2S) + Y b !? could be Y b 5S - Y b mixture
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Y(4320) More Y’s from BaBar and Belle
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Y(4360) = Y(4320) ? Y(4360) = Y(4320) ? Y(4660) ! Y(4660) ! Two Y’s ? PRL99, (2007) PRL99, (2007)
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Scan ? Compare Hadrons vs (1S) + , (2S) + Yb?Yb?Yb?Yb? PRL 98, (2007 ) Scan could uncover rich structure ! Yb?Yb?Yb?Yb?’ 6/2005 “scan” 5 points, 30 pb each (stat error) fit with 5S = 110 MeV ~ 8 fb (1 fb pts)
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ A Super B Factory can study in detail.
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Observation of “ (5S)” (1S) + , (2S) + Evidence for “ (5S)” (3S) + , (1S) K + K Assuming (5S) properties, B ( (5S) (1S) + ) = B ( (5S) (2S) + ) = B ( (5S) (3S) + ) = B ( (5S) (1S) K + K ) = w/ partial widths 0.52 – 0.85 MeV ⇐ Very Large New preliminary Bf for (4S) (1S) + Summary arXiv: Cf. ~ MeV for (4S) (1S) + Y(4260)-ish
New (5S) decays from Belle George W.S. Hou (NTU) SLAC Expt ’ l, 11/15/ Thank you !