observation of anomalous e + e - ( ns ) h + h - production at ( 5s ) energies

New (5S) decays from Belle George W.S. Hou (NTU) NTHU HEP, 11/08/2007 1

Observation of Anomalous e+e (nS) h+h

Production at (5S) Energies

November 8, 2007, HEP Seminar @ NTHU

http://www.ntu.edu.tw/chinese/PageN.php

http://www.ntu.edu.tw/chinese/PageB.php



Outline

• Motivation

• (4S), (3S) (1S) + Template

• Dataset on (5S)

• Event Selection for (nS) h+h

• Results

• Discussion

• Summary All Results Pre

liminary

Preliminary

arXiv:0710.2577

To be submitted soon to PRL



Motivation



Motivation I: because it’s there

ee ≃ 0.27 keV

ee ≃ 0.13 keV ≃ 110 MeV ≃ 20.5 MeV

Belle has ~ 20 fb1 (5S) data

expect limits only ...

11020.5

~ 1.7 x 105

477 fb1



Motivation II: Enhancement?

PRD 74, 017504 (2006)




PRD 74, 017504 (2006)Conceived during FPCP2006April ’06 in Vancouver



Motivation of Motivation

I sat through this

SLAC Expt’l Seminar ...



Motivation of Motivation

Shuwei YE



Motivation II: Enhancement?Y(

4260

)



Shuwei YE

Note to myself~ 7/13/05



Shuwei YE



Xb/Yb George W.S. Hou (NTU) ICHEP’06, 7/28/06 11

Mass: Use QQg hybrid (CLEO favored) lattice work to illustrate- 10600 - 10900 MeV (Michael)

Could scale down, ∵ccg prediction typically higher than Y(4260)➯ Could show up in ISR on Could show up in ISR on (5S)(5S)

- 10900 – 11000 MeV (Juge, Kuti, Morningstar)Predicted ccg state ~ 4260

➯ Prefers Higher Energy ScanPrefers Higher Energy Scan

Width: 100 MeV (~ Yc = Y(4260)) plausible

Product BR:

Assume

~Could be smaller or larger

Guestimates

BaBar/CLEO

─

─

─

10865



Backdrop: Data on (5S) • 1985: CUSB, CLEO @ CESR ~ 116 pb

• 2003: CLEO III @ CESR ~ 0.42 fb1

• June 2005: Belle @ KEKB ~ 1.86 fb1 engineering run

• June 9-31, 2006: Belle @ KEKB ≅ 21.7 fb1



1.86 fb1 (2S) (3S) (4S) (5S)

Rough study ~ 9/2006 (post summer)

Hint of events above background

Took a year to analyze 21.7 fbTook a year to analyze 21.7 fb11, solely because of “computing”., solely because of “computing”.



(3S), (4S) (1S) + Template

Old subject



(3S) (1S) + Understanding

2.9 fb1

1.14 fb1

PRD 7575, 072001 (2007)

(for (3S) + + nothing)

PRL 9898, 132001 (2007)



(3S)(1S)

(2S)(1S)

(3S)(2S)

3S3S

2S2S

1S1S

More can be done at Belle ...

528 ± 24

1315 ± 39

4556 ± 70

Data from (3S) Run



(2S)(1S) (3S)(1S)

(3S)(2S)

Brown-Cahn Model

Brown-Cahn Model Moxhay Model

CLEO Model

PRD 7575, 072001 (2007)☞ allow E

E term !

Much betterdata than CLEO

CLEO Model CLEO Model

CLEO Model

Data from (3S) Run



(4S) (1S) + Template

2S3S

4S

477 fb1

211 fb1

PRD 7575, 071103(R) (2007)

PRL 9696, 232001 (2006)

~ 104



(2S)(1S) (3S)(1S)

(4S)(1S)

CLEO Model CLEO Model

Brown-Cahn Model

Data on (4S)



(3S), (4S) (1S) + Template

Published papers by Belle, BaBar and CLEOSo, (5S) straightforward.



Dataset on (5S)



14 countries, 55 institutes, ~400 collaborators

IHEP, ViennaITEPKanagawa U.KEKKorea U.Krakow Inst. of Nucl. Phys.Kyoto U. Kyungpook Nat’l U. EPF Lausanne Jozef Stefan Inst. / U. of Ljubljana / U. of MariborU. of Melbourne

BINPChiba U.U. of CincinnatiEwha Womans U.Fu-Jen Catholic U.Fu-Jen Catholic U.U. of GiessenGyeongsang Nat’l U.Hanyang U.U. of HawaiiHiroshima Tech.IHEP, BeijingIHEP, Moscow

Nagoya U.Nara Women’s U.National Central U.National Central U.National Taiwan U.National Taiwan U.National United U.National United U.Nihon Dental CollegeNiigata U.Nova GoricaOsaka U.Osaka City U.Panjab U.Peking U.Princeton U.RikenSaga U.USTC

Seoul National U.Shinshu U.Sungkyunkwan U.U. of SydneyTata InstituteToho U.Tohoku U.Tohuku Gakuin U.U. of TokyoTokyo Inst. of Tech.Tokyo Metropolitan U.Tokyo U. of Agri. and Tech.INFN TorinoToyama Nat’l CollegeVPIYonsei U.

International Collaboration: BelleInternational Collaboration: Belle



e+ source

Ares RF cavity

Belle detector

World record: L = 1.7118 x 1034/cm2/sec

SCC RF(HER)

ARES(LER)

8 x 3.5 GeV 22 mrad crossing

~ 1 km in diameter

Mt. Tsukuba

KEKBBelle

since 1999

First successful op. of Crab cavities

The KEKB ColliderThe KEKB Collider


http://jp.f35.mail.yahoo.co.jp/ym/ShowLetter/ringanimation2M.gif?box=Inbox&MsgId=2406_9445966_98224_1696_384623_0_1738_499387_3403004772&bodyPart=1.4&filename=ringanimation2M.gif&tnef=&YY=43275&order=down&sort=date&pos=0&view=a&head=b

http://kekb.jp/


/ KL detection

14/15 lyr. RPC+Fe

Central Drift Chambersmall cell +He/C2H6

CsI(Tl)

Aerogel Cherenkov Counter n=1.015~1.030

Si Vertex Detector3(4) lyr. DSSD

TOF

SC Solenoid1.5T

8 GeV e

3.5 GeV e16X

ACC (PID)

ECL

SVDKLM

CDC

Belle DetectorBelle Detector



Dataset on (5S) Main Purpose

e.g.



Event Selection for (nS) h+h

h = , K



Event Selection for (nS) h+h Track Prompt: within 5 cm of IP in z (beam direction) 1 cm in transverse

hh

X0

Muon ID; loose h = , K No other charged tracks with pT > 100 MeV/c2

|M( - M((nS))| < 150 MeV/c2 (3) (nS) candidate

cos < 0.95 reject e

’s faking ’s

Electron ID

h = K case Kaon ID

Main bkg : Main bkg : ++ ++

ee++ee that mimic that mimic (1S)e(1S)e++ee (conversions)

Remark: Looser than (4S) (1S) + analysis Crosschecks w/ (4S) and (3S)



[→ ee

3S3S

2S2S

1S1S

21.7 fb1

e+e (nS) h+hat 10.87 GeV

Signal box to optimize on background



Results



2S3S

4S2S3S

4S

(4S) (1S) +

Expect to vanish

“(5S)” (1S) +, (2S) +

(2S) +

3S 4S>

““(5S)”(5S)”

““(5S)”(5S)”

(1S) +

Striking ! Striking !

1S1S

2S2S

3S3S



RemarksRemarks

Structure at ~ 0.84 GeV/c2 below 3S: “(5S)” → (2S) +

↳ (1S) + X

““(5S)”(5S)” : single ECM energy at 10.87 GeV No clear indication of radiative tail

2S

3S

4S

e+e (1S) +

>

““(5S)”(5S)”

some other reflection ?



“(5S)” (nS) +, (1S) K+K

(1S) +

(2S) +

(3S)(3S) ++

(1S)(1S) KK++KK

3.2

square box gives ~ 3.9

14

20

4.9

Signal box to optimize on background



Yield: Unbinned extended ML Fit

signalyield

bkgyield

signal PDF[two Gaussians

bkg PDF[linear [linear ⇐ ⇐ optimze boxoptimze box

2019325

5.24.520.2

15186

4.03.310.5

20 14

4.9 3.2

(1S) + (2S) +

(1S) K+K(3S) +



Brown-Cahn Model

phase space

M() and cos Hel Distributions

(1S) + (2S) +

Efficiency estimate: re-weighted MC according to dataN.B. other two modes use B-C model due to limited statistics

cos Hel

CLEO’07



Systematic Uncertainty

SourceSource (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%



Summary Table

N.B. Resonance cross section 0.302 ± 0.015 nb at 10.87 GeV PRD 98, 052001 (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 Yb state?

Assume “(5S)” = (5S)PDG value taken for (nS) properties

Need Scan to tellN.B.(5S) ee 0.13 keV≃ normal



Discussion



Scan ?Scan ?

YYbb!?!?

10.75 10.8 10.85 10.9 10.95 11.0

PRL 9898, 052001 (2007)6/2005 “scan”5 points,30 pb each (stat error)

fit with = 110 MeV

~ 8 fb~ 8 fb

Compare (1S) +,(2S) +vs Hadrons



No Indication !

No Indication !

Certainly “Anomalous” !



Y(4320)Y(4320)

More Y’s from BaBar and Belle



Y(4360)Y(4360) == Y(4320) ?Y(4320) ?

Y(4660) !Y(4660) !

Two Y’s ?Two Y’s ?



Scan ?Scan ?

Compare (1S) +,(2S) +vs Hadrons

YYbb!?!?

10.75 10.8 10.85 10.9 10.95 11.0

PRL 9898, 052001 (2007)6/2005 “scan”5 points,30 pb each (stat error)

fit with = 110 MeV

~ 8 fb~ 8 fb

Scan could uncover richer structure !



477 fb1

Corrected (4S) (1S) +

7.943.9Uncover from this study - Data and signal yield correct - Efficiency estimate for signal normalization was wrong

161593

112 fb

New preliminary Result:4+0.18

0.17

10 0.091.06 ±=BfkeV 0.332.17Γ ± +0.37

0.35=• Based on new data skim (112 fb) w/ 4x efficiency• Now consistent w/ BaBar

Revised publication coming soon



• 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

% 0.050.030.53

% 0.110.060.78

% 0.070.480.180.15

% 0.0100.0610.0160.014

arXiv:0710.2577

Cf. ~ 0.018 MeV for (4S) (1S) +


observation of anomalous e + e - ( ns ) h + h - production at ( 5s ) energies

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