Tenchini, R (reprint author), Univ Pisa, Dipartimento Fis, Ist Nazl Fis Nucl, Sez Pisa, I-56010 Pisa, Italy.
Deuteron and anti-deuteron production in Z decays has been observed in the ALEPH experiment at LER The production rate of anti-deuterons is measured to be (5.9 +/- 1.8 +/- 0.5) x 10(-6) per hadronic Z decay in the anti-deuteron momentum range from 0.62 to 1.03 GeV/c. The coalescence parameter B-2, which characterizes the likelihood of anti-deuteron production, is measured to be 0.0033 +/- 0.0013 GeV2 in Z decays. These measurements indicate that the production of anti-deuterons is suppressed in e(+)e(-) collisions compared to that in pp and photoproduction collisions. (c) 2006 Elsevier B.V. All rights reserved.