Published in:
Physical Review D 75,1 (2007)
Link to original published article:
http://dx.doi.org/10.1103/PhysRevD.75.012009
Abstract
Using CLEO data, we study the production of the antideuteron, (d) over bar, in Upsilon(nS) resonance decays and the nearby continuum. The branching ratios obtained are B-dir(Upsilon(1S)->(d) over barX)=(3.36 +/- 0.23 +/- 0.25)x10(-5), B(Upsilon(1S)->(d) over barX)=(2.86 +/- 0.19 +/- 0.21)x10(-5), and B(Upsilon(2S)->(d) over barX)=(3.37 +/- 0.50 +/- 0.25)x10(-5), where the "dir" superscript indicates that decays produced via reannihilation of the b (b) over bar pair to a gamma(*) are removed from both the signal and the normalizing number of Upsilon(1S) decays in order to isolate direct decays of the Upsilon(1S) to ggg, gg gamma. Upper limits at 90% C.L. are given for B(Upsilon(4S)->(d) over barX)< 1.3x10(-5), and continuum production sigma(e(+)e(-)->(d) over barX)< 0.031 pb. The Upsilon(2S) data is also used to extract a limit on chi(bJ)->(d) over barX. The results indicate enhanced deuteron production in ggg, gg gamma hadronization compared to gamma(*)-> q (q) over bar. Baryon number compensation is also investigated with the large Upsilon(1S)->(d) over barX sample.
Keywords
Astronomy & Astrophysics;; Physics, Particles & Fields
Date of this Version
January 2007