Mixing and time-dependent CP violation in beauty at LHCb Katya - PowerPoint PPT Presentation

Moriond EW 2019 Mixing and time-dependent CP violation in beauty at LHCb Katya Govorkova on behalf of the LHCb Collaboration

Weak phase Katya Govorkova Moriond EW 2019 21 March 2019 2 CP violation in interference between direct decay and decay after mixing CP violation in B ⁰ s _ Decays of B ⁰ s (B ⁰ s ) to J/ψ h ˖ h ˗ S c J/ ψ V ∗ bc c b V cs W + B 0 s s s h ⁺ h ⁻ φ + s

CP violation in interference between direct decay and decay after mixing 2 Weak phase @lisbouche Katya Govorkova Moriond EW 2019 21 March 2019 CP violation in B ⁰ s _ Decays of B ⁰ s (B ⁰ s ) to J/ψ h ˖ h ˗ S c c J/ ψ J/ ψ u, c, t V bc V ts b V ∗ s c bc c b V ∗ cs W − V cs B 0 W W s W + B 0 s V ts s b s s s u, c, t h ⁺ h ⁻ φ h ⁺ h ⁻ φ + s s

Weak phase Katya Govorkova Moriond EW 2019 21 March 2019 2 CP violation in interference between direct decay and decay after mixing CP violation in B ⁰ s _ Decays of B ⁰ s (B ⁰ s ) to J/ψ h ˖ h ˗ S c c J/ ψ J/ ψ u, c, t V bc V ts b V ∗ s c bc c b V ∗ cs W − V cs B 0 W W s W + B 0 s V ts s b s s s u, c, t h ⁺ h ⁻ φ h ⁺ h ⁻ φ + s s 𝜚 s = 𝜚 mix - 2 𝜚 dec

Weak phase Katya Govorkova Moriond EW 2019 21 March 2019 2 CP violation in interference between direct decay and decay after mixing CP Weak phase CP violation in B ⁰ s _ Decays of B ⁰ s (B ⁰ s ) to J/ψ h ˖ h ˗ S c c J/ ψ J/ ψ u, c, t V bc V ts b V ∗ s c bc c b V ∗ cs W − V cs B 0 W W s W + B 0 s V ts s b s s s u, c, t h ⁺ h ⁻ φ h ⁺ h ⁻ φ + s s 𝜚 s = 𝜚 mix - 2 𝜚 dec s - s h ⁺ h ⁻ φ h ⁺ h ⁻ φ u, c, t s b s s s V ts W W B 0 s W − B 0 s W + V ∗ cs V cs s c b c b V ts u, c, t V bc bc V ∗ J/ ψ J/ ψ c c S

New Physics! 3 Katya Govorkova Moriond EW 2019 21 March 2019 [CKM fitter] CP violation in B ⁰ s * Sensitive probe of New Physics in B ⁰ s mixing * Precise test of Standard Model through the measurement of 𝜚 s ≈ − 2 arg ( V ts V* cb ) = − 0.03686 +0.00096 0.10 tb ϕ SM − 0.00068 rad excluded at CL > 0.95 ε excluded area has CL > 0.95 γ s K V cs V* 0.05 m & m ∆ ∆ s d If 𝝔 sexp ≉ 𝝔 sSM m ∆ V α d ub α sb 0.00 η β s β -0.05 s γ sin 2 β NP CKM ε f i t t e r K Summer 18 -0.10 -0.10 -0.05 0.00 0.05 0.10 ρ sb

New Physics! 3 Katya Govorkova Moriond EW 2019 21 March 2019 [CKM fitter] CP violation in B ⁰ s * Sensitive probe of New Physics in B ⁰ s mixing * Precise test of Standard Model through the measurement of 𝜚 s ≈ − 2 arg ( V ts V* cb ) = − 0.03686 +0.00096 0.10 tb ϕ SM − 0.00068 rad excluded at CL > 0.95 ε excluded area has CL > 0.95 γ s K V cs V* 0.05 m & m ∆ ∆ s d If 𝝔 sexp ≉ 𝝔 sSM m ∆ V α d ub α sb 0.00 η β s β -0.05 s γ sin 2 β NP CKM ε f i t t e r K Summer 18 -0.10 -0.10 -0.05 0.00 0.05 0.10 ρ sb

Katya Govorkova Moriond EW 2019 21 March 2019 4 Measurement of CPV at LHCb

Katya Govorkova Moriond EW 2019 21 March 2019 5 μ˗ μ˖ h˖ h˗ J/ψ p p Inside the VELO Measurement of CPV at LHCb B ⁰ s flies ~ 1cm B ⁰ s

Katya Govorkova J/ψ Measurement of CPV at LHCb Inside the VELO p Moriond EW 2019 21 March 2019 p h˗ h˖ μ˖ μ˗ 5 Helicity angles formalism B ⁰ s flies ~ 1cm B ⁰ s h - h + h - h +

6 Katya Govorkova Moriond EW 2019 21 March 2019 Measurement of CPV at LHCb Angular analysis is required to disentangle CP-even and CP-odd final state admixture

6 Angular analysis is required to disentangle CP-even and - decay time resolution - efficiency as a function of decay time and angles - mistag probability of flavour tagging CP-odd final state admixture Measurement of CPV at LHCb Katya Govorkova Moriond EW 2019 21 March 2019 d 4 Γ dt d Ω ∼ ∑ f k ( Ω ) ε ( t , Ω ) (1 − 2 ω ) h k ( t | B 0 ω h k s ) ⊗ G ( t | σ t ) σ t Ω ε Ω Ω k ω ε σ t

≈ CP-even Angular analysis is required to disentangle CP-even and - decay time resolution - efficiency as a function of decay time and angles - mistag probability of flavour tagging 6 ≈ CP-odd CP-odd final state admixture Katya Govorkova Measurement of CPV at LHCb Moriond EW 2019 21 March 2019 d 4 Γ dt d Ω ∼ ∑ f k ( Ω ) ε ( t , Ω ) (1 − 2 ω ) h k ( t | B 0 ω h k s ) ⊗ G ( t | σ t ) σ t Ω ε Ω Ω k ω ε σ t h k = e −Γ s t ( a k cosh ΔΓ s t + b k sinh ΔΓ s t h k + c k cos( Δ m s t ) + d k sin( Δ m s t )) 2 2 Γ s = Γ H + Γ L ΔΓ s = Γ L − Γ H 2 s > + q | ¯ | B L > = p | B 0 B 0 ¯ s > A f λ = η q s > − q | ¯ p A f | B H > = p | B 0 B 0 s >

7 Katya Govorkova Moriond EW 2019 21 March 2019 Analyses strategy [LHCB-PAPER-2019-013] arXiv:1903.05530 Using 2015 (0.3 fb -1 ) and 2016 (1.6 fb -1 ) data B ⁰ s →J/ψ π ˖ π ˗ B ⁰ s →J/ψ K ˖ K ˗ in preparation measure 𝜚 s , |λ| and

7 Katya Govorkova Moriond EW 2019 21 March 2019 Analyses strategy [LHCB-PAPER-2019-013] arXiv:1903.05530 Using 2015 (0.3 fb -1 ) and 2016 (1.6 fb -1 ) data to test the Heavy Quark Expansion B ⁰ s →J/ψ π ˖ π ˗ B ⁰ s →J/ψ K ˖ K ˗ in preparation measure 𝜚 s , |λ| and ΔΓ s and Γ s - Γ B ⁰ prediction of Γ s / Γ B ⁰ = 1.0006 ± 0.0025

arXiv:1903.05530 entirely CP-odd since the final state is almost to test the Heavy Quark Expansion 7 Using 2015 (0.3 fb -1 ) and 2016 (1.6 fb -1 ) data [LHCB-PAPER-2019-013] Analyses strategy Moriond EW 2019 21 March 2019 Katya Govorkova B ⁰ s →J/ψ π ˖ π ˗ B ⁰ s →J/ψ K ˖ K ˗ in preparation measure 𝜚 s , |λ| and ΔΓ s and Γ s - Γ B ⁰ Γ H - Γ B ⁰ prediction of Γ s / Γ B ⁰ = 1.0006 ± 0.0025

since the final state is almost Katya Govorkova Moriond EW 2019 21 March 2019 Analyses strategy [LHCB-PAPER-2019-013] arXiv:1903.05530 Using 2015 (0.3 fb -1 ) and 2016 (1.6 fb -1 ) data 7 helicity angles to test the Heavy Quark Expansion Simultaneous fit to the decay time and three entirely CP-odd B ⁰ s →J/ψ π ˖ π ˗ B ⁰ s →J/ψ K ˖ K ˗ in preparation measure 𝜚 s , |λ| and ΔΓ s and Γ s - Γ B ⁰ Γ H - Γ B ⁰ prediction of Γ s / Γ B ⁰ = 1.0006 ± 0.0025

Using 2015 (0.3 fb -1 ) and 2016 (1.6 fb -1 ) data helicity angles Simultaneous fit to the decay time and three entirely CP-odd since the final state is almost to test the Heavy Quark Expansion 7 in 6 m(K ˖ K ˗ ) bins arXiv:1903.05530 [LHCB-PAPER-2019-013] Analyses strategy Moriond EW 2019 21 March 2019 Katya Govorkova B ⁰ s →J/ψ π ˖ π ˗ B ⁰ s →J/ψ K ˖ K ˗ in preparation measure 𝜚 s , |λ| and ΔΓ s and Γ s - Γ B ⁰ Γ H - Γ B ⁰ prediction of Γ s / Γ B ⁰ = 1.0006 ± 0.0025 See YS talk by J.Zonneveld ) 2 c 10000 Weighted cands. / (0.6 MeV/ LHCb LHCb 𝜒 contribution Preliminary 8000 6000 4000 2000 0 1000 1020 1040 + − m(K K ) [MeV/ c 2 ]

since the final state is almost in 6 m(K ˖ K ˗ ) bins and m(π ˖ π ˗ ) 7 helicity angles Simultaneous fit to the decay time and three entirely CP-odd to test the Heavy Quark Expansion arXiv:1903.05530 Using 2015 (0.3 fb -1 ) and 2016 (1.6 fb -1 ) data [LHCB-PAPER-2019-013] Analyses strategy Moriond EW 2019 21 March 2019 Katya Govorkova B ⁰ s →J/ψ π ˖ π ˗ B ⁰ s →J/ψ K ˖ K ˗ in preparation measure 𝜚 s , |λ| and ΔΓ s and Γ s - Γ B ⁰ Γ H - Γ B ⁰ prediction of Γ s / Γ B ⁰ = 1.0006 ± 0.0025 See YS talk by J.Zonneveld ) Yields/ (15 MeV) 2 LHCb f (980) c 10000 Weighted cands. / (0.6 MeV/ 0 LHCb Data and fit f (1500) LHCb 0 𝜒 contribution Preliminary 3 f (1790) 10 8000 0 f (1270) 2 f '(1525) 2 NR 6000 2 10 4000 10 2000 0 1 1000 1020 1040 0.5 1 1.5 2 + − m(K K ) [MeV/ c 2 ] m [GeV] π π

8 Katya Govorkova Decay time efficiency Decay time resolution Flavour tagging Selection TD fit for Moriond EW 2019 21 March 2019 Measurement of φ s Selection efficiency (Ω) 𝜚 s |λ| ΔΓ s Γ s/H - Γ B ⁰