Measurement of ratios of fragmentation fractions for bottom hadrons in pp collisions at {radical}(s)=1.96 TeV

Journal Article · Tue Apr 01 00:00:00 EDT 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.77.072003· OSTI ID:21249914

Aaltonen, T; Maki, T; Mehtala, P; Orava, R; Osterberg, K; Saarikko, H; Remortel, N van ^[1]; Adelman, J; Brubaker, E; Fedorko, W T; Grosso-Pilcher, C; Kim, Y K; Kwang, S; Levy, S; Paramonov, A A; Schmidt, M A; Shochet, M; Wolfe, C; Yang, U K; Yorita, K ^[2]

---

1. Division of High Energy Physics, Department of Physics, University of Helsinki and Helsinki Institute of Physics, FIN-00014, Helsinki (Finland)
2. Enrico Fermi Institute, University of Chicago, Chicago, Illinois 60637 (United States)

This paper describes the first measurement of b-quark fragmentation fractions into bottom hadrons in Run II of the Tevatron Collider at Fermilab. The result is based on a 360 pb{sup -1} sample of data collected with the CDF II detector in pp collisions at {radical}(s)=1.96 TeV. Semileptonic decays of B{sup 0}, B{sup -}, and B{sub s}{sup 0} mesons, as well as {lambda}{sub b}{sup 0} baryons, are reconstructed. For an effective bottom hadron p{sub T} threshold of 7 GeV/c, the fragmentation fractions are measured to be f{sub u}/f{sub d}=1.054{+-}0.018(stat){sub -0.045}{sup +0.025}(sys){+-}0.058(B), f{sub s}/(f{sub u}+f{sub d})=0.160{+-}0.005(stat){sub -0.010}{sup +0.011}(sys){sub -0.034}{sup +0.057}(B), and f{sub {lambda}{sub b}}/(f{sub u}+f{sub d})=0.281{+-}0.012(stat){sub -0.056}{sup +0.058}(sys){sub -0.087}{sup +0.128}(B), where the uncertainty B is due to uncertainties on measured branching ratios. The value of f{sub s}/(f{sub u}+f{sub d}) agrees within one standard deviation with previous CDF measurements and the world average of this quantity, which is dominated by LEP measurements. However, the ratio f{sub {lambda}{sub b}}/(f{sub u}+f{sub d}) is approximately twice the value previously measured at LEP. The approximately 2{sigma} discrepancy is examined in terms of kinematic differences between the two production environments.

• OSTI ID: 21249914
• Journal Information: Physical Review. D, Particles Fields, Vol. 77, Issue 7; Other Information: DOI: 10.1103/PhysRevD.77.072003; (c) 2008 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MINUS MESONS
B NEUTRAL MESONS
B QUARKS
B S MESONS
BARYONS
BRANCHING RATIO
FERMILAB
FERMILAB COLLIDER DETECTOR
FERMILAB TEVATRON
FRAGMENTATION
GEV RANGE
LAMBDA B NEUTRAL BARYONS
LEP STORAGE RINGS
PROTON-PROTON INTERACTIONS
SEMILEPTONIC DECAY
TEV RANGE 01-10