A measurement of the Bs→J/ψϕ decay parameters, updated to include flavour tagging is reported using 4.9fb−1 of integrated luminosity collected by the ATLAS detector from sqrt(s)=7TeV pp collisions recorded in 2011 at the LHC. The values measured for the physical parameters are: ϕsΔΓΓs|A∥(0)|2|A0(0)|2δ⊥=0.12±0.25(stat.)±0.05(syst.)rad0.053±0.021(stat.)0.010(syst.)ps−10.677±0.007(stat.)±0.004(syst.)ps−10.220±0.008(stat.)±0.009(syst.)0.529±0.006(stat.)±0.012(syst.)3.89±0.47(stat.)±0.11(syst.)rad where the parameter ΔΓ is constrained to be positive. The S-wave contribution was measured and found to be compatible with zero. Results for ϕs and ΔΓ are also presented as 68% and 95% likelihood contours, which show agreement with the Standard Model expectations.
Flavour tagged time dependent angular analysis of the B_s -> J/Psi phi decay and extraction of Delta Gamma_s and the weak phase phi_s in ATLAS
GORINI, Edoardo;PRIMAVERA, Margherita;SPAGNOLO, Stefania Antonia;VENTURA, Andrea
2014-01-01
Abstract
A measurement of the Bs→J/ψϕ decay parameters, updated to include flavour tagging is reported using 4.9fb−1 of integrated luminosity collected by the ATLAS detector from sqrt(s)=7TeV pp collisions recorded in 2011 at the LHC. The values measured for the physical parameters are: ϕsΔΓΓs|A∥(0)|2|A0(0)|2δ⊥=0.12±0.25(stat.)±0.05(syst.)rad0.053±0.021(stat.)0.010(syst.)ps−10.677±0.007(stat.)±0.004(syst.)ps−10.220±0.008(stat.)±0.009(syst.)0.529±0.006(stat.)±0.012(syst.)3.89±0.47(stat.)±0.11(syst.)rad where the parameter ΔΓ is constrained to be positive. The S-wave contribution was measured and found to be compatible with zero. Results for ϕs and ΔΓ are also presented as 68% and 95% likelihood contours, which show agreement with the Standard Model expectations.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
