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_. e + e - J/ y (cc) at s ≈ 10.6 GeV. S.L. Olsen (U of Hawai’i) Representing elle. QWG 2004 Worksop IHEP Beijing. Pinch-hitting for (visaless) Henryk Palka. INS Krakow. 2001: Belle & BaBar report on e + e - J/ y X @ s ≈ 10.6 GeV. BaBar: PRL 87, 162002.
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_ e+e- J/y (cc) at s≈10.6 GeV S.L. Olsen (U of Hawai’i) Representing elle QWG 2004 Worksop IHEP Beijing
Pinch-hitting for (visaless)Henryk Palka INS Krakow
2001: Belle & BaBar report on e+e-J/y X @s≈10.6 GeV BaBar: PRL 87, 162002 Belle: PRL 88,052001 L =21 fb-1 L =32 fb-1 ZZZZ PJ/y(GeV/c) PJ/y(GeV/c)
2002: look in detail at MX Pasha Pakhlov ITEP-Moscow
Eureka! Eureka! Eureka! Eureka!
4 surprizes! select J/yl+l- + >2 chrgd trks • no signal for MX<Mhc • clear hc, cc0 &hc’ signals • s(e+e- J/yhc) > 10x theory • s(e+e- J/y cc • s(e+e- J/y all) L=101 fb-1 ‘ 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
Possibilities “hc” peak has some contamination from e+e- ggJ/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
2003 Check recoil mass scale using e+e-gy(2S) p+p- J/y Mx (p+p-J/y) InferDMrecoil(J/y)<3 MeV
2003: Fit for J/y J/y (+ other) components hc ‘ L=155 fb-1 cc0 hc
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
Try to reconstruct hcKSKp, or 4K Find 3 events expect 2.6 MC No ISR b ISR >10MeV
2003: look at e+e-y(2S) X hc ‘ cc0 hc similar pattern
Cross sections Theory (Braaten & Lee) : <2.3±1 fb
2004: more data, more surprizes! L= 287 fb -1
Summary • Continuum e+e- J/y X is full of surprizes • s(e+e- J/yhc) > 10 x theory • e+e- gg J/y J/y contamination is small • No evidence for e+e- J/y glueball • e+e-J/y cc/e+e-J/y X ≈ 0.6 ± 0.2 • many times expecations • evidence for a new charmonium-like state • Mx continuum turns on near Mx≈Mhc
Belle’s experience more data more surprizes
Look at e+e-J/y D(D(*)) • Reconstruct a J/y & a D • use D0K-p+ & D+K-p+p+ • Determine recoil mass
Look at M(DD(*)) 3940 MeV 9.9 ± 3.3 evts (4.5 s) DD* cc0DD* ‘ DD 4.1 ± 2.2 evts (2.1 s) hcDD “
Select regions of cosqprod(hel)and then fit Mx distributions
2002 2003 L=101 fb-1 L=155 fb-1 - • e+e-J/y (cc) > e+e-J/yglue • s(e+e-J/yhc) 10x theory • evidence for hc’ • ggJ/y J/y negligible • confirm hc’ 2004 287 fb -1 ‘ hc hc cc0 non-zero continuum below DD threshold 4th peak!!