CP Asymmetries Research Articles

Tasting flavoured Majorana dark matter

We study a simplified model of flavoured Majorana dark matter in the Dark Minimal Flavour Violation framework. The model extends the Standard Model by a dark matter flavour triplet and a scalar mediator, through which the new dark fermions couple to right-handed up-type quarks. This interaction is governed by a new coupling matrix λ which is assumed to constitute the only new source of flavour and CP violation. We analyse the parameter space of this model by using constraints from collider searches, D0− overline{D} 0 mixing, cosmology and direct dark matter searches. Throughout our study, we point out crucial differences between the Majorana and Dirac dark matter cases. After performing a combined analysis within the context of all the experimental constraints mentioned above, we analyse which flavour for the dark matter particle is preferred by experimental data. We further investigate if this model is capable of explaining the large measured value of the direct CP asymmetry Delta {A}_{mathrm{CP}}^{mathrm{dir}} in charm decays. We find that significant enhancements with respect to the Standard Model expectation are compatible with all constraints, and even the central value of the measurement can be reached. We also advertise the flavour-violating final state with two same-sign top quarks produced in association with missing transverse energy as a smoking-gun signature for flavoured Majorana dark matter at the LHC.

Linear Seesaw in A5′ Modular Symmetry With Leptogenesis

In this study, we investigate the implication of modular Γ5′≃A5′ symmetry on neutrino oscillation phenomenology in the linear seesaw framework. In order to achieve the well-defined mass structure for the light active neutrinos as dictated by the linear seesaw mechanism, we introduce six heavy fermion fields along with a pair of weightons to retain the holomorphic nature of the superpotential. The notable feature of modular symmetry is that it reduces the usage of flavon fields significantly. In addition, the Yukawa couplings transform non-trivially under the flavor symmetry group and are expressed in terms of the Dedekind eta functions, the q expansion of which renders numerical simplicity in calculations. We demonstrate that the model framework diligently accommodates all the neutrino oscillation data. Alongside, we also investigate the effect of CP asymmetry generated from the decay of lightest heavy fermions to explain the observed baryon asymmetry through the phenomenon of leptogenesis.

Asymmetry in flavour changing electromagnetic transitions of vector-like quarks

Vector-like quarks have been of interest for a plethora of experimentally motivated reasons and have come under increased investigation recently due to their inclusion to the Standard Model (SM) appreciably improving global fits to several flavour physics and precision electroweak measurements. The addition of vector-like quark singlets breaks the unitarity of the Cabibbo-Kobayashi-Maskawa (CKM) matrix and enables tree-level flavour changing neutral (FCN) vertices. The resulting radiative flavour changing decays of these particles through the electromagnetic transition dipole moment are a key means to study their properties and search for them at experiments like the Large Hadron Collider (LHC). Despite these radiative decays providing such a clean experimental signature, an explicit analytical study of the branching ratios and CP violation resulting from these loop level processes has thus far evaded attention. We provide the formulation for the decay rates and CP asymmetry resulting from a combination of the imaginary components of the loop integrals and complex phases in the quark mixing matrix. We then apply our analytical results to study phenomenology of these states for several global fits pertaining to vector-like isosinglets t′ and b′. We find that clean collider signatures and polarisation observables can be generated for both t′ and b′.

Probing scalar dark matter oscillations with neutrino oscillations

If ultra-light dark matter (ULDM) exists and couples to neutrinos, it can be discovered via time-periodic variations in the neutrino mass and mixing parameters. We analyze the current bounds on such a scenario and establish the sensitivity expected for both time-averaged and time-resolved modulations in future neutrino oscillation experiments. We place a special emphasis in our analysis on time modulations of the CP violating mixing phase. We illustrate with a toy model the case where the leading modulation effect can be CP violating while the effect on CP conserving parameters is suppressed. We show a unique imprint that a time-averaged CP violating modulation of ULDM can leave in neutrino oscillations, while direct CP asymmetries vanish.

Estimating QCD-factorization amplitudes through SU(3) symmetry in Brightarrow P P decays

We estimate the potential size of the weak annihilation amplitudes in QCD factorization as allowed by experimental data. To achieve this goal, we establish a connection between the amplitudes in the QCD factorization and the so-called topological and SU(3)-invariant descriptions. Our approach is based purely on the analysis of the tensor structure of the decay amplitudes. By focusing on the processes Brightarrow P P and considering data from CP asymmetries and branching fractions, we perform a global fit to the SU(3)-irreducible quantities assuming minimal theoretical bias. Subsequently we translate the outcome to the QCD factorization decomposition, and find that the most constrained weak annihilation amplitudes are below 0.04. However, in view of the large uncertainties in several of the experimental input parameters, values up to sim 0.3 are allowed in certain cases.

CP asymmetry in the angular distributions of \u03c4 \u2192 KS\u03c0\u03bd\u03c4 decays. Part II. General effective field theory analysis

In this work, we proceed to study the CP asymmetry in the angular distributions of τ → KSπντ decays within a general effective field theory framework including four-fermion operators up to dimension-six. It is found that, besides the commonly considered scalar-vector interference, the tensor-scalar interference can also produce a non-zero CP asymmetry in the angular distributions, in the presence of complex couplings. Using the dispersive representations of the Kπ form factors as inputs, and taking into account the detector efficiencies of the Belle measurement, we firstly update our previous SM predictions for the CP asymmetries in the same four Kπ invariant-mass bins as set by the Belle collaboration. Bounds on the effective couplings of the non-standard scalar and tensor interactions are then obtained under the combined constraints from the CP asymmetries measured in the four bins and the branching ratio of τ−→ KSπ−ντ decay, with the numerical results given respectively by operatorname{Im}left[{hat{upepsilon}}_Sright] = −0.008 ± 0.027 and operatorname{Im}left[{hat{upepsilon}}_Tright] = 0.03 ± 0.12, at the renormalization scale μτ = 2 GeV in the overline{mathrm{MS}} scheme. Using the best-fit values, we also find that the distributions of the CP asymmetries can deviate significantly from the SM expectation in almost the whole Kπ invariant-mass region. Nevertheless, the current bounds on operatorname{Im}left[{hat{upepsilon}}_Sright] and operatorname{Im}left[{hat{upepsilon}}_Tright] are still plagued by large experimental uncertainties, but will be improved with more precise measurements from the Belle II experiment as well as the proposed Tera-Z and STCF facilities. Assuming further that the non-standard scalar and tensor interactions originate from a weakly-coupled heavy new physics well above the electroweak scale, the SU(2)L invariance of the resulting SMEFT Lagrangian would indicate that very strong limits on operatorname{Im}left[{hat{upepsilon}}_Sright] and operatorname{Im}left[{hat{upepsilon}}_Tright] could also be obtained from the neutron electric dipole moment and the {D}^0-{overline{D}}^0 mixing. With the bounds from these processes taken into account, it is then found that, unless there exist extraordinary cancellations between the new physics contributions, neither the scalar nor the tensor interaction can produce any significant effects on the CP asymmetries (relative to the SM predictions) in the processes considered, especially under the “single coefficient dominance” assumption.

Charmless B_srightarrow V S decays in PQCD approach

In this work, we investigate the B_srightarrow V S decays in the perturbative QCD approach, where V and S denote the vector meson and scalar meson respectively. Based on the two-quark structure, considering two different scenarios for describing the scalar mesons, we calculate the branching fractions and the direct CP asymmetries of all B_srightarrow VS decays. Most branching fractions are predicted to be at 10^{-7} to 10^{-5}, which could be measured in the LHCb and Belle-II experiments, especially for these color-allowed decays B_srightarrow kappa (800)(K_0^*(1430))K^* and B_srightarrow K_0^{*-}(1430)rho ^+. It is found that the branching fractions of B_srightarrow K_0^{*0}(1430){bar{K}}^{*0} and B_srightarrow K_0^{*+}(1430){bar{K}}^{*-} are very sensitive to the scenarios, which can be used to determine whether K_0^{*0}(1430) belongs to the ground state or the first excited state, if the data were available. We also note that some decays have large direct CP asymmetries, some of which are also sensitive to the scenarios, such as the B_s rightarrow a_0^+(1450)K^{*-} and the B_srightarrow f_0(1500) K^{*0} decays. Since the experimental measurements of B_srightarrow VS decays are on the way, combined with the available data in the future, we expect the theoretical predictions will shed light on the structure of the scalar mesons.

BSM sources of CP violation at future long baseline experiments

Different new physics models can introduce new sources of CP violation in the neutrino oscillation probabilities. We studied the potential of the DUNE experiment to look for them, in the case of sterile neutrinos and Non-Standard Interactions, measuring only the CP asymmetries in different oscillation channels. We show that if a high energy flux will be used, the asymmetry related to the νμ → νe appearance channel could be very useful to search for hints of new physics.

Study of electroweak penguin B decays at Belle II experiment

The electroweak b → sll (l = e, µ) transition is a flavor-changing neutral current process that mediates through a one-loop penguin diagram. The decay is considered to be a good probe for the New Physics as particles predicted in the beyond Standard Model theories can enter into the loop. The exclusive decay B → K (*) l + l − was first observed by the Belle experiment and it provides many observables such as the branching fraction, CP asymmetry, forward-backward asymmetry, and other angular observables. Recently, the LHCb experiment has reported some clue of a lepton flavor universality violation from the branching fraction ratio of the B → Kµ + µ − and B → Ke + e − decays. In this presentation, we report the status of the B → Kl + l − decay analysis at the Belle II experiment which started the data taking in 2019. We also, present an activity at the Belle II Chulalongkorn University group where we study the B → KJ/ψ decay which has the same topology as the B → Kl + l − .

Resonant leptogenesis and TM_1 mixing in minimal type-I seesaw model with S_4 symmetry

We present an S_4 flavour symmetric model within a minimal seesaw framework resulting in mass matrices that leads to TM_1 mixing. Minimal seesaw is realized by adding two right-handed neutrinos to the Standard Model. The model predicts Normal Hierarchy (NH) for neutrino masses. Using the constrained six-dimensional parameter space of the model, we have evaluated the effective Majorana neutrino mass, which is the parameter of interest in neutrinoless double beta decay experiments. The possibility of explaining baryogenesis via resonant leptogenesis is also examined within the model. A non-zero, resonantly enhanced CP asymmetry generated from the decay of right-handed neutrinos at the TeV scale is studied, considering flavour effects. The evolution of lepton asymmetry is discussed by solving the set of Boltzmann equations numerically and obtain the value of baryon asymmetry to be |eta _B| = 6.3 times 10^{-10} with the choice of right-handed neutrino mass, M_1 = 10 TeV and mass splitting, d simeq 10^{-8}.

Complete analysis of all B→πK decays

The Standard Model (SM) predicts that $\Delta A_{\rm CP}$, the difference between the direct CP asymmetries for the modes $B^+\to \pi^0 K^+$ and $B^0\to \pi^- K^+$ that are related by weak isospin, should be close to zero. There has been a recent claim by the LHCb Collaboration that the measured value of $\Delta A_{\rm CP}$ shows an uncomfortable tension with the SM prediction, almost at the $8\sigma$ level. Motivated by this claim, we critically re-examine the data on all the $B\to \pi K$ modes, including the CP asymmetries and CP-averaged branching fractions. From a combined Bayesian analysis with the topological amplitudes and their phases as the free parameters, we find that the best-fit region has a large overlap with the parameter space favoured in the SM, albeit with some enhancement for the electroweak penguin and the colour-suppressed tree amplitudes, consistent with the findings of earlier studies. We find that in this SM-like region, $\Delta A_{\rm CP}$ is more than 5$\sigma$ away from zero and the tension with the global average, as well as the LHCb result, is within $2\sigma$. Thus we conclude that there is not yet enough motivation to go beyond the SM.

Non-unitary leptonic flavor mixing and CP violation in neutrino-antineutrino oscillations

If massive neutrinos are Majorana particles, then the lepton number should be violated in nature and neutrino-antineutrino oscillations να↔ν‾β (for α,β=e,μ,τ) will definitely take place. In the present paper, we study the properties of CP violation in neutrino-antineutrino oscillations with the non-unitary leptonic flavor mixing matrix, which is actually a natural prediction in the canonical seesaw model due to the mixing between light and heavy Majorana neutrinos. The oscillation probabilities P(να→ν‾β) and P(ν‾α→νβ) are derived, and the CP asymmetries Aαβ≡[P(να→ν‾β)−P(ν‾α→νβ)]/[P(να→ν‾β)+P(ν‾α→νβ)] are also calculated. Taking into account current experimental bounds on the leptonic unitarity violation, we show that the CP asymmetries induced by the non-unitary mixing parameters can significantly deviate from those in the limit of a unitary leptonic flavor mixing.

Effect of K0−K¯0 mixing on CP and CPT violations in Bc±→B±KS,L0 decays

The large data sample of the $B_c$ meson collected at the LHC experiment and the HL-LHC experiment provides us the opportunity to study the $B_c$ decays and the related physics. In this paper, we investigate the effect of $K^0-\bar{K}^0$ mixing on the the branching ratios, CP violations and CPT violations in the $B_{c}^{\pm}\rightarrow B^{\pm} K_{S,L}^{0}$ decays. We find that some of the $B_c^{\pm}\rightarrow B^{\pm} K_{S,L}^0\rightarrow f_{B^{\pm}} f_{K_{S,L}^0}$ decay chains have large branching ratios, whose maximum value can exceed the order of $10^{-6}$, the minimum number of $B_c^\pm$ events times efficiency for observing the decays at three standard deviations (3$\sigma$) level is about $ 10^6$. We study the CP asymmetries in the $B_c^{\pm}\rightarrow B^{\pm} K_{S,L}^0$ decays and find that the CP asymmetries can exceed the order of $10^{-3}$, which are dominated by $K^0-\bar{K}^0$ mixing. We give the most promising processes to observe the CP violations and the ranges of the numbers of $B_c^\pm$ events-times-efficiency needed to observe the CP asymmetries at a significance of 3$\sigma$ in these decays. We investigate the possibility to constraint the CPT violation parameter $z$ in the $B_c^{\pm}\rightarrow B^{\pm} K_{S,L}^0\rightarrow f_{B^{\pm}} f_{K_{S,L}^0}$ decays and give the most promising processes to constraint the parameter $z$.

Time-reversal asymmetries and angular distributions in \u039bb \u2192 \u039bV

We study the spin correlations to probe time-reversal (T) asymmetries in the decays of Λb→ ΛV (V = ϕ, ρ0, ω, K∗0). The eigenstates of the T-odd operators are obtained along with definite angular momenta. We obtain the T-odd spin correlations from the complex phases among the helicity amplitudes. We give the angular distributions of Λb→ Λ(→ pπ−)V (→ PP′) and show the corresponding spin correlations, where P(′) are the pseudoscalar mesons. Due to the helicity conservation of the s quark in Λ, we deduce that the polarization asymmetries of Λ are close to −1. Since the decay of Λb→ Λϕ in the standard model (SM) is dictated by the single weak phase from the product of CKM elements, {V}_{tb}{V}_{ts}^{ast } , the true T and CP asymmetries are suppressed, providing a clean background to test the SM and search for new physics. In the factorization approach, as the helicity amplitudes in the SM share the same complex phase, T-violating effects are absent. Nonetheless, the experimental branching ratio of Br(Λb→ Λϕ) = (5.18 ± 1.29) × 10−6 suggests that the nonfactorizable effects or some new physics play an important role. By parametrizing the nonfactorizable contributions with the effective color number, we calculate the branching ratios and direct CP asymmetries. We also explore the possible T-violating effects from new physics.

Hilbert series for leptonic flavor invariants in the minimal seesaw model

In this paper, we examine the leptonic flavor invariants in the minimal see-saw model (MSM), in which only two right-handed neutrino singlets are added into the Standard Model in order to accommodate tiny neutrino masses and explain cosmological matter-antimatter asymmetry via leptogenesis mechanism. For the first time, we calculate the Hilbert series (HS) for the leptonic flavor invariants in the MSM. With the HS we demonstrate that there are totally 38 basic flavor invariants, among which 18 invariants are CP-odd and the others are CP-even. Moreover, we explicitly construct these basic invariants, and any other flavor invariants in the MSM can be decomposed into the polynomials of them. Interestingly, we find that any flavor invariants in the effective theory at the low-energy scale can be expressed as rational functions of those in the full MSM at the high-energy scale. Practical applications to the phenomenological studies of the MSM, such as the sufficient and necessary conditions for CP conservation and CP asymmetries in leptogenesis, are also briefly discussed.

New physics in rare B decays after Moriond 2021

The anomalies in rare B decays endure. We present results of an updated global analysis that takes into account the latest experimental input – in particular the recent results on R_K and BR(B_s rightarrow mu ^+mu ^-) – and that qualitatively improves the treatment of theory uncertainties. Fit results are presented for the Wilson coefficients of four-fermion contact interactions. We find that muon specific Wilson coefficients C_9 simeq -0.73 or C_9 = -C_{10} simeq -0.39 continue to give an excellent description of the data. If only theoretically clean observables are considered, muon specific C_{10} simeq 0.60 or C_9=-C_{10} simeq -0.35 improve over the Standard Model by sqrt{Delta chi ^2} simeq 4.7sigma and sqrt{Delta chi ^2} simeq 4.6sigma , respectively. In various new physics scenarios we provide predictions for lepton flavor universality observables and CP asymmetries that can be tested with more data. We update our previous combination of ATLAS, CMS, and LHCb data on BR(B_s rightarrow mu ^+mu ^-) and BR(B^0rightarrow mu ^+mu ^-) taking into account the full two-dimensional non-Gaussian experimental likelihoods.

The charm of 331

We perform a detailed analysis of flavour changing neutral current processes in the charm sector in the context of 331 models. As pointed out recently, in the case of Z′ contributions in these models there are no new free parameters beyond those already present in the Bd,s and K meson systems analyzed in the past. As a result, definite ranges for new Physics (NP) effects in various charm observables could be obtained. While generally NP effects turn out to be small, in a number of observables they are much larger than the tiny effects predicted within the Standard Model. In particular we find that the branching ratio of the mode D0→ μ+μ−, despite remaining tiny, can be enhanced by 6 orders of magnitude with respect to the SM. We work out correlations between this mode and rare Bd,s and K decays. We also discuss neutral charm meson oscillations and CP violation in the charm system. In particular, we point out that 331 models provide new weak phases that are a necessary condition to have non-vanishing CP asymmetries. In the case of ∆ACP, the difference between the CP asymmetries in D0→ K+K− and D0→ π+π−, we find that agreement with experiment can be obtained provided that two conditions are verified: the phases in the ranges predicted in 331 models and large hadronic matrix elements.

Measurement of branching fractions and search for CP violation in D0 \u2192 \u03c0+\u03c0\u2212\u03b7, D0 \u2192 K+K\u2212\u03b7, and D0 \u2192 \u03d5\u03b7 at Belle

We measure the branching fractions and CP asymmetries for the singly Cabibbo-suppressed decays D0 → π+π−η, D0 → K+K−η, and D0 → ϕη, using 980 fb−1 of data from the Belle experiment at the KEKB e+e− collider. We obtainBD0→π+π−η=1.22±0.02stat±0.02syst±0.03Bref×10−3,BD0→K+K−η=1.80−0.06+0.07stat±0.04syst±0.05Bref×10−4,BD0→ϕη=1.84±0.09stat±0.06syst±0.05Bref×10−4,\\documentclass[12pt]{minimal}\t\t\t\t\\usepackage{amsmath}\t\t\t\t\\usepackage{wasysym}\t\t\t\t\\usepackage{amsfonts}\t\t\t\t\\usepackage{amssymb}\t\t\t\t\\usepackage{amsbsy}\t\t\t\t\\usepackage{mathrsfs}\t\t\t\t\\usepackage{upgreek}\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\t\t\t\t\\begin{document}$$ {\\displaystyle \\begin{array}{c}\\mathcal{B}\\left({D}^0\\to {\\pi}^{+}{\\pi}^{-}\\eta \\right)=\\left[1.22\\pm 0.02\\left(\\mathrm{stat}\\right)\\pm 0.02\\left(\\mathrm{syst}\\right)\\pm 0.03\\left({\\mathcal{B}}_{\\mathrm{ref}}\\right)\\right]\\times {10}^{-3},\\\\ {}\\mathcal{B}\\left({D}^0\\to {K}^{+}{K}^{-}\\eta \\right)=\\left[{1.80}_{-0.06}^{+0.07}\\left(\\mathrm{stat}\\right)\\pm 0.04\\left(\\mathrm{syst}\\right)\\pm 0.05\\left({\\mathcal{B}}_{\\mathrm{ref}}\\right)\\right]\\times {10}^{-4},\\\\ {}\\mathcal{B}\\left({D}^0\\to \\phi \\eta \\right)=\\left[1.84\\pm 0.09\\left(\\mathrm{stat}\\right)\\pm 0.06\\left(\\mathrm{syst}\\right)\\pm 0.05\\left({\\mathcal{B}}_{\\mathrm{ref}}\\right)\\right]\\times {10}^{-4},\\end{array}} $$\\end{document}where the third uncertainty ( mathcal{B} ref) is from the uncertainty in the branching fraction of the reference mode D0 → K−π+η. The color-suppressed decay D0 → ϕη is observed for the first time, with very high significance. The results for the CP asymmetries areACPD0π+π−η=0.9±1.2stat±0.5syst%,ACPD0→K+K−η=−1.4±3.3stat±1.1syst%,ACPD0→ϕη=−1.9±4.4stat±0.6syst%.\\documentclass[12pt]{minimal}\t\t\t\t\\usepackage{amsmath}\t\t\t\t\\usepackage{wasysym}\t\t\t\t\\usepackage{amsfonts}\t\t\t\t\\usepackage{amssymb}\t\t\t\t\\usepackage{amsbsy}\t\t\t\t\\usepackage{mathrsfs}\t\t\t\t\\usepackage{upgreek}\t\t\t\t\\setlength{\\oddsidemargin}{-69pt}\t\t\t\t\\begin{document}$$ {\\displaystyle \\begin{array}{c}{A}_{CP}\\left({D}^0\\ {\\pi}^{+}{\\pi}^{-}\\eta \\right)=\\left[0.9\\pm 1.2\\left(\\mathrm{stat}\\right)\\pm 0.5\\left(\\mathrm{syst}\\right)\\right]\\%,\\\\ {}{A}_{CP}\\left({D}^0\\to {K}^{+}{K}^{-}\\eta \\right)=\\left[-1.4\\pm 3.3\\left(\\mathrm{stat}\\right)\\pm 1.1\\left(\\mathrm{syst}\\right)\\right]\\%,\\\\ {} ACP\\ \\left({D}^0\\to \\phi \\eta \\right)=\\left[-1.9\\pm 4.4\\left(\\mathrm{stat}\\right)\\pm 0.6\\left(\\mathrm{syst}\\right)\\right]\\%.\\end{array}} $$\\end{document}The results for D0 → π+π−η are a significant improvement over previous results. The branching fraction and ACP results for D0 → K+K−η, and the ACP result for D0 → ϕη, are the first such measurements. No evidence for CP violation is found in any of these decays.

Study of B_{(s)} rightarrow (pi pi )(Kpi ) decays in the perturbative QCD approach

In this work, we provide estimates of the branching ratios, direct CP asymmetries and triple product asymmetries in B_{(s)} rightarrow (pi pi )(Kpi ) decays in the perturbative QCD approach, where the pi pi and Kpi invariant mass spectra are dominated by the vector resonances rho (770) and K^*(892), respectively. Some scalar backgrounds, such as f_0(500,980) rightarrow pi pi and K^*_0(1430) rightarrow Kpi are also accounted for. The rho (700) is parametrized by the Gounaris-Sakurai function. The relativistic Breit-Wigner formula for the f_0(500) and Flatté model for the f_0(980) are adopted to parameterize the time-like scalar form factors F_S(omega ^2). We also use the D.V. Bugg model to parameterize the f_0(500) and compare the relevant theoretical predictions from different models. While in the region of Kpi invariant mass, the K^*_0(1430) is described with the LASS lineshape and the K^*(892) is modeled by the Breit-Wigner function. We find that the decay rates for the considered decay modes agree with currently available data within errors. As a by-product, we extract the branching ratios of two-body decays B_{(s)} rightarrow rho (770)K^*(892) from the corresponding four-body decay modes and calculate the relevant polarization fractions. Our prediction of longitudinal polarization fraction for B^0rightarrow rho (770)^0 K^*(892)^0 decay deviates a lot from the recent LHCb measurement, which should be resolved. It is shown that the direct CP asymmetries are large due to the sizable interference between the tree and penguin contributions, but they are small for the tree-dominant or penguin-dominant processes. The PQCD predictions for the “true” triple product asymmetries are small which are expected in the standard model, and consistent with the current data reported by the LHCb Collaboration. Our results can be tested by the future precise data from the LHCb and Belle II experiments.

A Review of CP Violation Measurements in Charm at LHCb

The LHCb experiment has been able to collect the largest sample ever produced of charm-hadron decays, performing a number of measurements of observables related to CP violation in the charm sector. In this document, the most recent results from LHCb on the search of direct CP violation in D0→Ks0Ks0, D(s)+→h+π0 and D(s)+→h+η decays are summarised, in addition to the most precise measurement of time-dependent CP asymmetry in D0→h+h− decays and the first observation of mass difference between neutral charm-meson eigenstates.