Invariant-mass distribution of cc-bar in Upsilon(1S) -> cc-bar + X

Abstract

We calculate the invariant-mass distribution for the cc-bar pair produced in the inclusive Upsilon(1S) decay based on the color-singlet mechanism of the nonrelativistic quantum chromodynamics factorization approach at leading order in the bottom-quark velocity v_b in the meson rest frame. As the short-distance processes, we consider bb-bar -> g^*gg followed by g^* -> cc-bar and bb-bar -> gamma^* -> cc-bar at leading order in the strong coupling. The invariant-mass distribution of the bb-bar -> cc-bar gg contribution has a sharp peak just above the threshold and that of the bb-bar -> gamma^* -> cc-bar channel is concentrated at the maximally allowed kinematic end point. We predict that Gamma[Upsilon(1S) -> cc-bar+X]/Gamma[Upsilon(1S)->light hadrons] = 0.065 alpha_s, which is smaller than a previous result by about 20%.

15 pages, 1 figure

References in corpus (7)

• QCD corrections to J/psi and Upsilon production at hadron colliders
• Improved determination of color-singlet nonrelativistic QCD matrix elements for S-wave charmonium
• Resummation of Relativistic Corrections to e+ e- -> J/psi+eta_c
• Potential-model calculation of an order-v^2 NRQCD matrix element
• Inclusive Charm Production in chi_b Decays
• Inclusive Charm Production in Upsilon(nS) Decay
• Investigation of the bottomonium ground state η_b via its inclusive charm decays

Cited by in corpus (2)

• Inclusive double-quarkonium production at the Large Hadron Collider
• p p -> J/psi+Upsilon+X as a clean probe to the quarkonium production mechanism