Measurement of the parity-violating asymmetry parameter α[subscript b] and the helicity amplitudes for the decay Λ[0 over b] → J/ψΛ[superscript 0] with the ATLAS detector
A measurement of the parity-violating decay asymmetry parameter, α[subscript b], and the helicity amplitudes for the decay Λ[0 over b] → J/ψ(μ[superscript +]μ[superscript −])Λ[superscript 0](pπ[superscript −]) is reported. The analysis is based on 1400 Λ[0 over b] and [bar over Λ][0 over b] baryons...
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| Format: | Article |
| Language: | en_US |
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American Physical Society
2014
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| Online Access: | http://hdl.handle.net/1721.1/90883 https://orcid.org/0000-0002-7586-7253 |
| Summary: | A measurement of the parity-violating decay asymmetry parameter, α[subscript b], and the helicity amplitudes for the decay Λ[0 over b] → J/ψ(μ[superscript +]μ[superscript −])Λ[superscript 0](pπ[superscript −]) is reported. The analysis is based on 1400 Λ[0 over b] and [bar over Λ][0 over b] baryons selected in 4.6 fb[superscript −1] of proton–proton collision data with a center-of-mass energy of 7 TeV recorded by the ATLAS experiment at the LHC. By combining the Λ[0 over b] and [bar over Λ][0 over b] samples under the assumption of CP conservation, the value of α[subscript b] is measured to be 0.30 ± 0.16(stat) ± 0.06(syst). This measurement provides a test of theoretical models based on perturbative QCD or heavy-quark effective theory. |
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