Quark fragmentation within an identified jet

Journal Article · Thu Apr 01 04:00:00 EDT 2010 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.81.074009· OSTI ID:21409472

Procura, Massimiliano ^[1]; Stewart, Iain W ^[1]

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1. Center for Theoretical Physics, Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

We derive a factorization theorem that describes an energetic hadron h fragmenting from a jet produced by a parton i, where the jet invariant mass is measured. The analysis yields a 'fragmenting jet function' G{sub i}{sup h}(s,z) that depends on the jet invariant mass s, and on the energy fraction z of the fragmentation hadron. We show that G{sub i}{sup h} can be computed in terms of perturbatively calculable coefficients, J{sub ij}(s,z/x), integrated against standard nonperturbative fragmentation functions, D{sub j}{sup h}(x). We also show that h{integral}dzG{sub i}{sup h}(s,z) is given by the standard inclusive jet function J{sub i}(s) which is perturbatively calculable in QCD. We use soft collinear effective theory and for simplicity carry out our derivation for a process with a single jet, B{yields}Xhl{nu}, with invariant mass m{sub Xh}{sup 2}>>{Lambda}{sub QCD}{sup 2}. Our analysis yields a simple replacement rule that allows any factorization theorem depending on an inclusive jet function J{sub i} to be converted to a semi-inclusive process with a fragmenting hadron h. We apply this rule to derive factorization theorems for B{yields}XK{gamma} which is the fragmentation to a Kaon in b{yields}s{gamma}, and for e{sup +}e{sup -{yields}}(dijets)+h with measured hemisphere dijet invariant masses.

• OSTI ID: 21409472
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 7 Vol. 81; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
BEAUTY MESONS
BEAUTY PARTICLES
BOSONS
ELECTRON-POSITRON INTERACTIONS
ELEMENTARY PARTICLES
FACTORIZATION
FERMIONS
FIELD THEORIES
FRAGMENTATION
HADRONS
INTERACTIONS
KAONS
LEPTON-LEPTON INTERACTIONS
MASS
MESONS
PARTICLE INTERACTIONS
PSEUDOSCALAR MESONS
QUANTUM CHROMODYNAMICS
QUANTUM FIELD THEORY
QUARKS
STRANGE MESONS
STRANGE PARTICLES