Flavour Physics at LHCb -- 50 years of the KM paradigm

Abstract

The LHCb experiment is in operation since 2009 and has provided measurements of the KM matrix with unprecedented precision. 50 years after the original paper we are in the position of pinning down the parameters of the theory, or possibly to show its limitations. In these proceedings the status of LHCb is shown in a historical perspective, along with some anecdotes.

arXiv commentProceedings for the PTEP KM50 Special Section

References in corpus (125)

• Weak Decays Beyond Leading Logarithms
• Observation of a New Narrow Charmonium State in Exclusive B+-->K+ pi+pi- J/psi Decays
• Observation of a narrow charmonium-like state in exclusive B+ -> K+ pi+pi- J/psi decays
• Measurement of the Positive Muon Anomalous Magnetic Moment to 0.46 ppm
• Observation of $J/\psi p$ resonances consistent with pentaquark states in ${\Lambda }_b^0\to J/\psi K^{-}p$ decays
• The anomalous magnetic moment of the muon in the Standard Model
• CP Violation and the CKM Matrix: Assessing the Impact of the Asymmetric B Factories
• Test of lepton universality using $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays
• Evidence for an excess of B -> D(*) Tau Nu decays
• Heavy-Quark QCD Exotica
• Test of lepton universality with $B^0\to K^{\ast 0}{\ell }^{+}{\ell }^{-}$ decays
• Measurement of an Excess of B -> D(*) Tau Nu Decays and Implications for Charged Higgs Bosons
• Observation of Large CP Violation in the Neutral B Meson System
• Symmetries and Asymmetries of B -> K* mu+ mu- Decays in the Standard Model and Beyond
• Observation of CP violation in the B^0 meson system
• Observation of the rare $B_s^0\to {\mu }^{+}{\mu }^{-}$ decay from the combined analysis of CMS and LHCb data
• More Model-Independent Analysis of b->s Processes
• A Comparative Study of the Decays $B\to (K,K^{\ast }){\ell }^{+}{\ell }^{-}$ in Standard Model and Supersymmetric Theories
• Charm-loop effect in $B\to K^{(\ast )}{\ell }^{+}{\ell }^{-}$ and $B\to K^{\ast }\gamma$
• Measurement of the Differential Branching Fraction and Forward-Backword Asymmetry for B->K(*)l+l-
• Determination of the X(3872) meson quantum numbers
• Observation of structure in the $J/\psi$-pair mass spectrum
• Observation of an exotic narrow doubly charmed tetraquark
• Search for lepton-universality violation in $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ decays
• First evidence for the decay Bs -> mu+ mu-
• Test of lepton universality in beauty-quark decays
• Observation of Direct CP Violation in K_{S,L} to ππDecays
• Differential branching fractions and isospin asymmetries of $B\to K^{(\ast )}{\mu }^{+}{\mu }^{-}$ decays
• Study of the doubly charmed tetraquark $T_{cc}^{+}$
• Observation of Bs-Bsbar Oscillations
• Optimizing the basis of B->K*ll observables in the full kinematic range
• Measurement of $CP$-averaged observables in the $B^0\to K^{\ast 0}{\mu }^{+}{\mu }^{-}$ decay
• Observation of $CP$ violation in charm decays
• New physics in $b\to s$ transitions after LHC run 1
• Measurement of the ratio of branching fractions $\mathcal{B}(B_c^{+}\to J/\psi {\tau }^{+}{\nu }_{\tau })$/$\mathcal{B}(B_c^{+}\to J/\psi {\mu }^{+}{\nu }_{\mu })$
• Measurement of the $B_s^0\to {\mu }^{+}{\mu }^{-}$ branching fraction and effective lifetime and search for $B^0\to {\mu }^{+}{\mu }^{-}$ decays
• A precision measurement of direct CP violation in the decay of neutral kaons into two pions
• Amplitude analysis of the $B^{+}\to D^{+}{D}^{-}{K}^{+}$ decay
• Branching Ratio Measurements of $B_s$ Decays
• Probing New Physics Via the Transverse Amplitudes of B0-> K*0(-> K- pi+) l+l- at Large Recoil
• On the impact of power corrections in the prediction of B->K*mu+mu- observables
• Measurement of Branching Fractions and Rate Asymmetries in the Rare Decays B -> K(*) l+ l-
• Observation of new resonances decaying to $J/\psi K^{+}$ and $J/\psi \varphi$
• Bounds on the width, mass difference and other properties of X(3872) --> pi+pi-J/psi decays
• Observation of a Near-threshold $D^0{\bar{D}}^0{\pi }^0$ Enhancement in $B\to D^0{\bar{D}}^0{\pi }^{0}K$ Decay
• $B\to K{\ell }^{+}{\ell }^{-}$ decay at large hadronic recoil
• Direct CP Violating Asymmetry in B0 -> K+pi- Decays
• CP Asymmetries in bar B -> bar K* (-> bar K pi) l+ l- and Untagged bar B_s,B_s -> phi (-> K+ K-) l+ l- Decays at NLO
• Determination of the quark coupling strength $|V_{ub}|$ using baryonic decays
• Power-enhanced leading-logarithmic QED corrections to $B_q\to {\mu }^{+}{\mu }^{-}$
• On the single leptoquark solutions to the $B$-physics anomalies
• Angular analysis of the decay B0 to K*0 mu mu from pp collisions at sqrt(s) = 8 TeV
• Measurement of angular parameters from the decay ${\mathrm{B}}^0\to {\mathrm{K}}^{\ast 0}{\mu }^{+}{\mu }^{-}$ in proton-proton collisions at $\sqrt{s}=$ 8 TeV
• Observation of a $J/\psi \Lambda$ resonance consistent with a strange pentaquark candidate in $B^{-}\to J/\psi \Lambda \bar{p}$ decays
• Branching fraction measurements of the rare $B_s^0\to \varphi {\mu }^{+}{\mu }^{-}$ and $B_s^0\to f_2^{\prime }(1525){\mu }^{+}{\mu }^{-}$ decays
• $\Delta M_s$ theory precision confronts flavour anomalies
• Evidence for Direct CP Violation in B0 -> K+- pi-+ Decays
• First observation of CP violation in the decays of Bs mesons
• Observation of a peaking structure in the J/psi phi mass spectrum from B(+/-) to J/psi phi K(+/-) decays
• New observables in the decay mode anti-B --> anti-K*0 l+ l-
• Observation of the Baryonic Flavor-Changing Neutral Current Decay Lambda_b -> Lambda mu+ mu-
• Precision measurement of $CP$ violation in $B_s^0\to J/\psi K^{+}{K}^{-}$ decays
• Study of the lineshape of the ${\chi }_{c1}(3872)$ state
• Amplitude analysis of $B^{+}\to J/\psi \varphi K^{+}$ decays
• Measurement of the CP-violating phase phi_s in the decay Bs->J/psi phi
• Improved Theory Predictions and Global Analysis of Exclusive $\mathbf{b}\to \mathbf{s}{\mathbf{\mu }}^{+}{\mathbf{\mu }}^{-}$ Processes
• Test of lepton universality in $b\to s{\ell }^{+}{\ell }^{-}$ decays
• Measurement of the CP-violating phase ${\varphi }_s^{J/\psi \varphi }$ using the flavor-tagged decay $B_s^0\to J/\psi \varphi$ in 8 fb${}^{-1}$ of $p \barp$ collisions
• Constraints on Lepton Universality Violation from Rare $B$ Decays
• $\text{HEPfit}$: a Code for the Combination of Indirect and Direct Constraints on High Energy Physics Models
• Measurement of the $B_s^0\to {\mu }^{+}{\mu }^{-}$ decay properties and search for the $B^0\to {\mu }^{+}{\mu }^{-}$ and $B_s^0\to {\mu }^{+}{\mu }^{-}\gamma$ decays
• Quantum numbers of the $X(3872)$ state and orbital angular momentum in its ${\rho }^{0}J\psi$ decay
• Measurement of lepton universality parameters in $B^{+}\to K^{+}{\ell }^{+}{\ell }^{-}$ and $B^0\to K^{\ast 0}{\ell }^{+}{\ell }^{-}$ decays
• Rare $b$ decays meet high-mass Drell-Yan
• Observation of an excess of di-charmonium events in the four-muon final state with the ATLAS detector
• The ultimate theoretical error on gamma from B -> D K decays
• To (b)e or not to (b)e: No electrons at LHCb
• Implications of new evidence for lepton-universality violation in $b\to s{\ell }^{+}{\ell }^{-}$ decays
• Angular analysis of the $B^{+}\to K^{\ast +}{\mu }^{+}{\mu }^{-}$ decay
• Analysis of neutral $B$-meson decays into two muons
• Measurement of the Bottom-Strange Meson Mixing Phase in the Full CDF Data Set
• QED Corrections in $\bar{B}\to \bar{K}{\ell }^{+}{\ell }^{-}$ at the Double-Differential Level
• Tests of lepton universality using $B^0\to K_S^0{\ell }^{+}{\ell }^{-}$ and $B^{+}\to K^{\ast +}{\ell }^{+}{\ell }^{-}$ decays
• $B_s\to K\ell {\nu }_{\ell }$ and $B_{(s)}\to \pi (K){\ell }^{+}{\ell }^{-}$ decays at large recoil and CKM matrix elements
• More Indications for Lepton Nonuniversality in $b\to s{\ell }^{+}{\ell }^{-}$
• Measurement of Time-Dependent CP-Violating Asymmetries in B0 --> phi Ks0, K+ K- Ks0, and eta' Ks0 Decays
• Measurement of properties of B${}_{\mathrm{s}}^0\to {\mu }^{+}{\mu }^{-}$ decays and search for B${}^0\to {\mu }^{+}{\mu }^{-}$ with the CMS experiment
• Search for the X(4140) state in B+ to J/psi phi K+ decays
• Measurement of the B${}_{\mathrm{S}}^0$ $\to$ ${\mu }^{+}{\mu }^{-}$ decay properties and search for the B${}^0$ $\to$ ${\mu }^{+}{\mu }^{-}$ decay in proton-proton collisions at $\sqrt{s}$ = 13 TeV
• First observation of a doubly charged tetraquark and its neutral partner
• Observation of a resonance in $B^{+}\to K^{+}{\mu }^{+}{\mu }^{-}$ decays at low recoil
• Observation of the decay ${\Lambda }_b^0\to {\Lambda }_c^{+}{\tau }^{-}{\overline{\nu }}_{\tau }$
• Measurement of the ratios of branching fractions $\mathcal{R}(D^{\ast })$ and $\mathcal{R}(D^0)$
• $R(J/\psi )$ and $B_c^{-}\to J/\psi {\ell }^{-}{\bar{\nu }}_{\ell }$ Lepton Flavor Universality Violating Observables from Lattice QCD
• Standard Model predictions for $B\to K{\ell }^{+}{\ell }^{-}$, $B\to K{\ell }_1^{-}{\ell }_2^{+}$ and $B\to K\nu \bar{\nu }$ using form factors from $N_f=2+1+1$ lattice QCD
• Precise predictions for ${\Lambda }_b\to {\Lambda }_c$ semileptonic decays
• Test of lepton flavour universality using $B^0\to D^{\ast -}{\tau }^{+}{\nu }_{\tau }$ decays with hadronic $\tau$ channels
• Test of lepton universality with ${\Lambda }_b^0\to p{K}^{-}{\ell }^{+}{\ell }^{-}$ decays
• Measurement of the difference of time-integrated CP asymmetries in $D^0\to K^{-}{K}^{+}$ and $D^0\to {\pi }^{-}{\pi }^{+}$ decays
• $B_s\to K\ell \nu$ decay from lattice QCD
• Amplitude analysis of $B^0\to {\overline{D}}^0{D}_s^{+}{\pi }^{-}$ and $B^{+}\to D^{-}{D}_s^{+}{\pi }^{+}$ decays
• Measurement of the $CP$-violating phase ${\varphi }_s$ in $B_s^0\to J/\psi \varphi$ decays in ATLAS at 13 TeV
• Measurement of the CP-violating phase ${\varphi }_s$ in ${\bar{B}}_s^0\to D_s^{+}{D}_s^{-}$ decays
• First study of the CP-violating phase and decay-width difference in $B_s^0\to \psi (2S)\varphi$ decays
• On the significance of new physics in $b\to s{\ell }^{+}{\ell }^{-}$ decays
• Measurement of $CP$ observables in $B^{\pm }\to D{K}^{\pm }$ and $B^{\pm }\to D{\pi }^{\pm }$ with two- and four-body $D$ decays
• First observation of the decay $B_s^0\to K^{-}{\mu }^{+}{\nu }_{\mu }$ and a measurement of $|V_{ub}|/|V_{cb}|$
• Resonances and $CP$ violation in $B_s^0$ and ${\overline{B}}_s^0\to J/\psi K^{+}{K}^{-}$ decays in the mass region above the $\varphi (1020)$
• Measurement of the time-integrated $CP$ asymmetry in $D^0\to K^{-}{K}^{+}$ decays
• Measurement of the $CP$-violating phase ${\varphi }_{\mathrm{s}}$ in the B${}_{\mathrm{s}}^0$ $\to$ J$/\psi \varphi$(1020) $\to$ ${\mu }^{+}{\mu }^{-}$K${}^{+}$K${}^{-}$ channel in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• A precise measurement of the $B^0$ meson oscillation frequency
• Measurement of the CKM angle $\gamma$ in $B^{\pm }\to D{K}^{\pm }$ and $B^{\pm }\to D{\pi }^{\pm }$ decays with $D\to K_{\mathrm{S}}^0{h}^{+}{h}^{-}$
• Measurement of forward $W$ and $Z$ boson production in association with jets in proton-proton collisions at $\sqrt{s}=8$ TeV
• Observation of sizeable $\omega$ contribution to ${\chi }_{c1}(3872)\to {\pi }^{+}{\pi }^{-}J/\psi$ decays
• Observation of $CP$ violation in two-body $B_{(\mathrm{s})}^0$-meson decays to charged pions and kaons
• Measurement of the $CP$-violating phase ${\varphi }_s$ from $B_s^0\to J/\psi {\pi }^{+}{\pi }^{-}$ decays in 13 TeV $pp$ collisions
• New algorithms for identifying the flavour of $B^0$ mesons using pions and protons
• Study of $B^{-}\to D{K}^{-}{\pi }^{+}{\pi }^{-}$ and $B^{-}\to D{\pi }^{-}{\pi }^{+}{\pi }^{-}$ decays and determination of the CKM angle $\gamma$
• Study of the lineshape of $X(3872)$ using $B$ decays to $D^0\overline{D}{}^{\ast 0}K$
• Measurement of the CKM angle $\gamma$ and $B_s^0$-${\bar{B}}_s^0$ mixing frequency with $B_s^0\to D_s^{\mp }{h}^{\pm }{\pi }^{\pm }{\pi }^{\mp }$ decays
• The Rumble in the Meson: a leptoquark versus a $Z^{\prime }$ to fit $b\to s{\mu }^{+}{\mu }^{-}$ anomalies including 2022 LHCb $R_{K^{(\ast )}}$ measurements
• Evidence of a $J/\psi K_S^0$ structure in $B^0\to J/\psi \varphi K_S^0$ decays
• Precision measurement of $CP$ violation in the penguin-mediated decay $B_s^0\to \varphi \varphi$
• A study of $CP$ violation in the decays $B^{\pm }\to [K^{+}{K}^{-}{\pi }^{+}{\pi }^{-}{]}_D{h}^{\pm }$ ($h=K,\pi$) and $B^{\pm }\to [{\pi }^{+}{\pi }^{-}{\pi }^{+}{\pi }^{-}{]}_D{h}^{\pm }$
• Model-independent measurement of charm mixing parameters in $\bar{B}\to D^0(\to K_S^0{\pi }^{+}{\pi }^{-}){\mu }^{-}{\bar{\nu }}_{\mu }X$ decays