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arXiv · hep-ph/9303205

Gluon Fragmentation into Heavy Quarkonium

Eric Braaten·Tzu Chiang Yuan
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Abstract

The dominant production mechanism for heavy quark-antiquark bound states in very high energy processes is fragmentation, the splitting of a high energy parton into a quarkonium state and other partons. We show that the fragmentation functions $D(z,μ)$ describing these processes can be calculated using perturbative QCD. We calculate the fragmentation functions for a gluon to split into S-wave quarkonium states to leading order in the QCD coupling constant. The leading logarithms of $μ/m_Q$, where $μ$ is the factorization scale and $m_Q$ is the heavy quark mass, are summed up using Altarelli-Parisi evolution equations.

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Eric Braaten, Tzu Chiang Yuan. 1993-03-02. Gluon Fragmentation into Heavy Quarkonium. https://doi.org/10.1103/physrevlett.71.1673

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