Time-dependent angular analysis of the decay B[0 over s] → J/ψϕ and extraction of ΔΓ[subscript s] and the CP-violating weak phase ϕ[subscript s] by ATLAS
A measurement of B[0 over s] → J/ψϕ decay parameters, including the CP-violating weak phase ϕ[subscript s] and the decay width difference ΔΓ[subscript s] is reported, using 4.9 fb[superscript −1] of integrated luminosity collected in 2011 by the ATLAS detector from LHC pp collisions at a centre-of-m...
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| Format: | Article |
| Language: | en_US |
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Springer-Verlag
2014
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| Online Access: | http://hdl.handle.net/1721.1/84938 https://orcid.org/0000-0002-7586-7253 |
| Summary: | A measurement of B[0 over s] → J/ψϕ decay parameters, including the CP-violating weak phase ϕ[subscript s] and the decay width difference ΔΓ[subscript s] is reported, using 4.9 fb[superscript −1] of integrated luminosity collected in 2011 by the ATLAS detector from LHC pp collisions at a centre-of-mass energy s√ = 7 TeV. The mean decay width Γ[subscript s] and the transversity amplitudes |A [subscript 0](0)|[superscript 2] and |A [subscript ∥](0)|[superscript 2] are also measured. The values reported for these parameters are: ϕ[subscript s] = 0.22 ± 0.41 (stat.) ± 0.10 (syst.) rad; ΔΓ[subscript s] = 0.053 ± 0.021 (stat.) ± 0.010 (syst.) ps[superscript −1]; Γ[subscript s] = 0.677 ± 0.007 (stat.) ± 0.004 (syst.) ps[superscript −1]; |A[subscript 0](0)|[superscript 2] = 0.528 ± 0.006 (stat.) ± 0.009 (syst.); |A[subscript ∥](0)|[superscript 2] = 0.220 ± 0.008 (stat.) ± 0.007 (syst.) where the values quoted for ϕ[subscript s] and ΔΓ[subscript s] correspond to the solution compatible with the external measurements to which the strong phase δ[subscript ⊥] is constrained and where ΔΓ[subscript s] is constrained to be positive. The fraction of S-wave KK or f[subscript 0] contamination through the decays B[0 over s] → J/ψK[superscript +]K[superscript −](f[subscript 0]) is measured as well and is found to be consistent with zero. Results for ϕ[subscript s] and ΔΓ[subscript s] are also presented as 68%, 90% and 95% likelihood contours, which show agreement with Standard Model expectations. |
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