Logo image
Measurement of the parity-violating asymmetry parameter 𝛼𝑏 and the helicity amplitudes for the decay Λ0 𝑏→𝐽/𝜓⁢Λ0 with the ATLAS detector
Journal article   Open access   Peer reviewed

Measurement of the parity-violating asymmetry parameter 𝛼𝑏 and the helicity amplitudes for the decay Λ0 𝑏→𝐽/𝜓⁢Λ0 with the ATLAS detector

Trygve Buanes, Ørjan Dale, Gerald Eigen, Alex Kastanas, Wolfgang Liebig, Anna Lipniacka, Bertrand Martin Dit Latour, Peter Lundgaard Rosendahl, Heidi Sandaker, Therese B Sjursen, …
Physical review. D, Particles, fields, gravitation, and cosmology, Vol.89(9), 092009
05/27/2014
DOI: 10.1103/physrevd.89.092009
url
https://doi.org/10.1103/physrevd.89.092009View
Published (Version of record) Open Access

Abstract

A measurement of the parity-violating decay asymmetry parameter, αb, and the helicity amplitudes for the decay Λb0→J/ψ(μ+μ-)Λ0(pπ-) is reported. The analysis is based on 1400 Λb0 and Λ¯b0 baryons selected in 4.6 fb-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 Λb0 and Λ¯b0 samples under the assumption of CP conservation, the value of αb 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.
Elementary Particle Physics High Energy Physics Mathematics Physics Experiment Fysikk Kjerne Matematikk og naturvitenskap natural scienses Nuclear Nuclear Experiment og elementærpartikkelfysikk Phenomenology

Details

Metrics

10 Record Views
Logo image