A Crucial Test for Color-octet Production Mechanism in Z Decays
نویسندگان
چکیده
The direct production rates of D-wave charmonia in the decays of Z is evaluated. The color-octet production processes Z → DJ(cc̄)qq̄ are shown to have distinctively large branching ratios, the same order of magnitude as that of J/ψ prodution, as compared with other D-wave charmonium production mechanisms. This may suggest a crucial channel to test the color-octet mechanism as well as to observe the D-wave charmonium states in Z decays. In addition, a signal for the 3DJ charmonium as strong as J/ψ or ψ with large transverse momentum at the Tevatron should also be observed. PACS number(s):12.38.Bx, 14.40.Gx
منابع مشابه
Gluon Fragmentation to Dj Quarkonia and Test of Color-octet Production Mechanism
We report the recent progress in the studies of D-wave heavy quarkonia production from gluon fragmentation at the Tevatron and in Z decays, and the D-wave charmonia production in B decays. We show that the color-octet contributions are of crucial importance to the production of D-wave quarkonia. Signals, as strong as that for J/ψ and ψ′, should be seen for the D-wave charmonium in the processes...
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