Signatures of color-octet quarkonium production

Conference · Wed May 01 04:00:00 EDT 1996

OSTI ID:270832

Beneke, M

Quarkonium spectroscopy, decay and production has provided scientists with an interesting place to test their ideas on QCD ever since charmonium was discovered in 1974. Yet, the potential of perturbative QCD (PQCD) to treat production and decay has been fully exploited only recently in a development comparable to that of Heavy Quark Effective Theory for heavy-light mesons. About the same time, experiments measuring quarkonium production at large transverse momentum have confronted theorists with surprisingly large cross sections. These observations have led to the understanding that fragmentation and hadronization of color-octet quark-antiquark (Q{anti Q}) pairs are essential in the production process. Color-octet mechanisms were considered in quarkonium decays already a while ago. They were found to solve the problem of infrared divergences in P-wave decays in a systematic way. Taking them into account also in S-wave production, where they are not required by perturbative consistency in leading order of a nonrelativistic expansion, opens the promise of a quantitative description of quarkonium production. The author briefly reviews the nonrelativistic QCD picture of quarkonium production and its confrontation with experiment in various production processes.

• Research Organization: Stanford Linear Accelerator Center, Menlo Park, CA (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC03-76SF00515
• OSTI ID: 270832
• Report Number(s): SLAC-PUB--7173; CONF-9603183--2; ON: DE96013584; IN: HEP-PH/9605462
• Country of Publication: United States
• Language: English

Related Subjects

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QUANTUM CHROMODYNAMICS
QUARKONIUM
TESTING
TRANSVERSE MOMENTUM
Z NEUTRAL BOSONS