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Csorna, S. E.; Mestayer, M. D.; Panvini, R. S.; Word, G. B.; Yi, Xia; Bean, A.; Bobbink, G. J.; Brock, I. C.; Engler, A.; Ferguson, T.; Kraemer, R. W.; Rippich, C.; Sutton, R.B.; Vogel, H.; Bebek, C.; Berkelman, K.; Blucher, E.; Cassel, D. G.; Copie, T.; DeSalvo, R.; Dewire, J. W.; Ehrlich, R.; Galik, R. S.; Gilchriese, M.; Gittelman, B.; Gray, S. W.; Halling, A. M.; Hartill, D. L.; Heltsley, B. K.; Holzner, S.; Ito, M.; Kandaswamy, J.; Kowalewski, R.; Kreinick, D. L.; Kubota, Y.; Mistry, N. B.; Muêller, J.; Nordberg, E.; Ogg, M.; Peterson, D.; Perticone, D.; Pisharody, M.; Read, K. F.; Riley, D.; Silverman, A.; Stein, P. C.; Stone, S.; Sadoff, A. J.; Avery, P.; Besson, D.; Bowcock, T. J. V.; Giles, R. T.; Hassard, J.; Kinoshita, K.; Pipkin, F. M.; Wilson, Richard; Haas, P.; Hempstead, M.; Jensen, T.; Kagan, H.; Kass, R.; Behrends, S.; Gentile, Thomas R.; Guida, J. M.; Guida, J. A.; Morrow, F.; Poling, R.; Rosenfeld, C.; Thorndike, E. H.; Tipton, P.; Green, J.; Namjoshi, R.; Sannes, F.; Stone, R.; Alam, M. S.; Katayama, N.; Kim, I. J.; Sun, C. R.; Tanikella, V.; Bortoletto, D.; Chen, A.; Garren, L.; Goldberg, M.; Horwitz, N.; Jawahery, A.; Lubrano, P.; Moneti, G. C.; Trahern, C. G.

doi:10.1103/physrevlett.56.1222

Cited by 30 publications

(4 citation statements)

References 15 publications

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“…The linear rise with x γ predicted by LO perturbative QCD, Eq. (2), is not supported by the experimental data [8]. In particular for x γ ∼ > 0.7 the discrepancy is significant.…”

Section: Available At Leading Order One Finds [6]mentioning

confidence: 61%

QCD corrections to radiative Υ decays

Krämer

1999

Phys. Rev. D

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We have calculated the next-to-leading order perturbative QCD corrections to the photon energy spectrum in radiative Υ decays. The higher-order corrections significantly modify the shape of the spectrum, in particular at large photon energies, and thereby reduce the discrepancy between experimental data and previous leading-order predictions. The next-to-leading order calculation of the photon energy spectrum allows a more reliable determination of the strong coupling constant from radiative Υ decays by restricting the analysis to the region of the energy spectrum that can be described by NLO perturbation theory.

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“…The linear rise with x γ predicted by LO perturbative QCD, Eq. (2), is not supported by the experimental data [8]. In particular for x γ ∼ > 0.7 the discrepancy is significant.…”

Section: Available At Leading Order One Finds [6]mentioning

confidence: 61%

QCD corrections to radiative Υ decays

Krämer

1999

Phys. Rev. D

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“…R γ (%) CLEO 1.5 (Υ(1S)) [7] 2.54 ± 0.18 ± 0.14 ARGUS (Υ(1S)) [10] 3.00 ± 0.13 ± 0.18 Crystal Ball (Υ(1S)) [9] 2.7 ± 0.2 ± 0.4 CLEO II (Υ(1S)) [11] 2.77 ± 0.04 ± 0.15 CLEO III (Υ(1S)) 2.70 ± 0.01 ± 0.13 ± 0.24 CLEO III (Υ(2S)) 3.18 ± 0.04 ± 0.22 ± 0.41 CLEO III (Υ(3S)) 2.72 ± 0.06 ± 0.32 ± 0.37 TABLE V: Comparison with other experiments. Errors are statistical, systematic, and modeldependent (Field vs. Garcia/Soto), respectively.…”

Section: Methodsmentioning

confidence: 99%

“…This result seemed in conflict with the extant CUSB [6] data, which indicated a spectrum more similar to the lowest-order QCD prediction. A subsequent measurement by CLEO-I [7], however, favored Field's softened spectrum over lowest-order QCD. Given the poor resolution of the CLEO-I electromagnetic calorimeter, that measurement was also consistent with a subsequent modification to lowest-order QCD which calculated corrections at the endpoint [8] by summing leading logs of the form ln(1-x γ ).…”

Section: Introductionmentioning

confidence: 95%

Measurement of the direct photon momentum spectrum inΥ(1S),Υ(2S)
Besson¹,
Henderson²,
Pedlar³
et al. 2006
Phys. Rev. D
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Using data taken with the CLEO III detector at the Cornell Electron Storage Ring, we have investigated the direct photon spectrum in the decays Υ(1S) → γgg, Υ(2S) → γgg, Υ(3S) → γgg. The latter two of these are first measurements. Our analysis procedures differ from previous ones in the following ways: a) background estimates (primarily from π 0 decays) are based on isospin symmetry rather than a determination of the π 0 spectrum, which permits measurement of the Υ(2S) and Υ(3S) direct photon spectra without explicit corrections for π 0 backgrounds from, e.g., χ bJ states, b) we estimate the branching fractions with a parametrized functional form (exponential) used for the background, c) we use the high-statistics sample of Υ(2S)→ ππΥ(1S) to obtain a tagged-sample of Υ(1S)→ γ + X events, for which there are no QED backgrounds. We determine values for the ratio of the inclusive direct photon decay rate to that of the dominant three-gluon decay Υ → ggg (R γ = B(ggγ)/B(ggg)) to be: R γ (1S)=(2.70±0.01±0.13±0.24)%, R γ (2S)=(3.18±0.04±0.22±0.41)%, and R γ (3S)=(2.72±0.06±0.32±0.37)%, where the errors shown are statistical, systematic, and theoretical model-dependent, respectively. Given a value of Q 2 , one can estimate a value for the strong coupling constant α s (Q 2 ) from R γ .

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“…The predicted ratio of strong and leptonic decay rates (with Mr taken as 2mb), "From ratio r(ygg)Jr(ggg) � 2.03±0.53% (109).…”

Section: 1mentioning

confidence: 99%