e e- ? J/y (cc) at ?s

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ee- ? J/y (cc) at ?s10.6 GeV
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QWG 2004 Worksop IHEP Beijing

• S.L. Olsen (U of Hawaii)
• Representing elle

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Pinch-hitting for (visaless)Henryk Palka
INS Krakow
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2001 Belle BaBar report on
ee-?J/y X _at_?s10.6 GeV
BaBar PRL 87, 162002
Belle PRL 88,052001
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ZZZZ
PJ/y(GeV/c)
PJ/y(GeV/c)
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2002 look in detail at MX
Pasha Pakhlov ITEP-Moscow
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Eureka! Eureka! Eureka! Eureka!
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4 surprizes!
select J/y?ll- gt2 chrgd trks

• no signal for MXltMhc
• clear hc, cc0 hc signals
• s(ee- ? J/y hc) gt 10x theory
• s(ee- ? J/y cc
• s(ee- ? J/y all)

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hc
hc
cc0


0.6 0.2
E.Braaten J. Lee PRD 67, 054007 (2003) no
unknown non-perturbative parameters
K.Abe et al (Belle) PRL 89, 142001
NRQCD predicts this to be 0.1
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Possibilities

• hc peak has some
• contamination from
• ee- ?gg?J/yJ/y
• Bodwin, Lee Braaten PRL 90, 162001
• The hc peak has some
• glueball content (in addition
• to charmonium)
• Brodsky, Goldhaber Lee PRL 91, 112001
• Dulat, Hagiwara Lin hep-ph/04022230

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2003
Check recoil mass scale using ee- ?g y(2S)

?pp- J/y
Mx (pp-J/y)
Infer? DMrecoil(J/y)lt3 MeV
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2003
Fit for J/y J/y ( other) components
hc

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cc0
hc
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No significant contamination from ee- ? gg ?
J/y J/y
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2003
Angular distributions are consistent with
charmonium expectations
l
J/y
qhel
qprod
X
J/y
e-
e
glueball prediction 1 - 0.9cos2q
1 0.9 cos2q
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Try to reconstruct hc?KSKp, or 4K
Find 3 events expect 2.6
MC ? No ISR b ? ISR gt10MeV
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hc peak looks like an hc not like a glueball
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2003 look at ee- ?y(2S) X
hc

cc0
hc
similar pattern
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Cross sections
Theory (Braaten Lee) lt2.31 fb
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2004 more data, more surprizes!
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Summary

• Continuum ee- ? J/y X is full of surprizes
• s(ee- ?J/y hc) gt 10 x theory
• ee- ? gg ? J/y J/y contamination is small
• No evidence for ee- ?J/y glueball
• ee-?J/y cc/ee-?J/y X 0.6 0.2
• many times expecations
• evidence for a new charmonium-like state
• Mx continuum turns on near MxMhc

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Belles experience

• more data?
• more surprizes

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Backup Slides
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Look at ee-?J/y D(D())

• Reconstruct a J/y a D
• use D0?K-p D?K-pp
• Determine recoil mass

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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

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Select regions of cosqprod(hel)and then fit Mx
distributions
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2002
2003
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L155 fb-1
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• gg?J/y J/y negligible
• confirm hc

• ee-?J/y (cc) gt ee-?J/y glue
• s(ee-?J/y hc) 10x theory
• evidence for hc

2004
287 fb -1

hc
hc
cc0
non-zero continuum below DD threshold
4th peak!!