Observation of the Omega [subscript b][superscript -] baryon and measurement of the properties of the Xi[subscript b][superscript -] and Omega [subscript b][superscript -] baryons
Name
Aaltonen-2009-Observation.pdf
Size
1.04 MB
Format
Adobe PDF
Checksum (MD5)
70605a267f951810b4a915fd2a79098b
Author(s)
Xie, Si
Paus, Christoph M. E.
Knuteson, Bruce O.
Henderson, C.
Hahn, Kristian Allan
Goncharov, Maxim
Gomez-Ceballos, Guillelmo
Choudalakis, Georgios
Makhoul, Khaldoun
Bauer, Gerry P
Date Issued
October 2009
Journal
Physical Review D
Publisher
American Physical Society
Citation
CDF Collaboration et al. “Observation of the Omega b- baryon and measurement of the properties of the Xi b- and Omega b- baryons.” Physical Review D 80.7 (2009): 072003. © 2009 The American Physical Society
Version
Final published version
Abstract
We report the observation of the bottom, doubly-strange baryon Ω[subscript b][superscript -] through the decay chain Ω[subscript b][superscript -]→J/ψΩ[superscript -], where J/ψ→μ[superscript +]μ[superscript -], Ω[superscript -]→ΛK[superscript -], and Λ→pπ[superscript -], using 4.2 fb[superscript -1] of data from pp̅ collisions at √s=1.96 TeV, and recorded with the Collider Detector at Fermilab. A signal is observed whose probability of arising from a background fluctuation is 4.0×10[superscript -8], or 5.5 Gaussian standard deviations. The Ω[subscript b][superscript -] mass is measured to be 6054.4±6.8(stat)±0.9(syst) MeV/c[superscript 2]. The lifetime of the Ω[subscript b][superscript -] baryon is measured to be 1.13[subscript -0.40][superscript +0.53](stat)±0.02(syst) ps. In addition, for the Ξ[subscript b][superscript -] baryon we measure a mass of 5790.9±2.6(stat)±0.8(syst) MeV/c[superscript 2] and a lifetime of 1.56[subscript -0.25][superscript +0.27](stat)±0.02(syst) ps. Under the assumption that the Ξ[subscript b][superscript -] and Ω[subscript b][superscript -] are produced with similar kinematic distributions to the Λ[subscript b][superscript 0] baryon, we find σ(Ξ[subscript b][superscript -])B(Ξ[subscript b][superscript -]→J/ψΞ[superscript ]-)/σ(Λ[subscript b][superscript 0])B(Λ[subscript b][superscript 0]→J/ψΛ)=0.167[subscript -0.025][superscript +0.037](stat)±0.012(syst) and σ(Ω[subscript b][superscript -])B(Ω[subscript b][superscript -]→J/ψΩ[superscript -])/σ(Λ[subscript b][superscript -])B(Λ[subscript b][superscript -]→J/ψΛ)=0.045[subscript -0.012][superscript +0.017](stat)± 0.004(syst) for baryons produced with transverse momentum in the range of 6–20 GeV/c.
MIT Department
Massachusetts Institute of Technology. Laboratory for Nuclear Science
Terms of Use
Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.
Persistent DSpace Link
DOI of Published Version
http://dx.doi.org/10.1103/PhysRevD.80.072003
