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We present a brief update of our model-independent analyses of the b->s data presented in the articles published in Phys. Rev. D96 (2017) 095034 and Phys. Rev. D98 (2018) 095027 based on new data on R_K by LHCb, on R_{K^*} by Belle, and on B_{s,d}-> mu^+ mu^- by ATLAS.
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Recently, the LHCb collaboration has reported the excesses in the $b to s ll$ processes. One of the promising candidates for new physics to explain the anomalies is the extended Standard Model (SM) with vector-like quarks and leptons. In that model, Yukawa couplings between the extra fermions and SM fermions are introduced, adding extra scalars. Then, the box diagrams involving the extra fields achieve the $b to s ll$ anomalies. It has been known that the excesses require the large Yukawa couplings of leptons, so that this kind of model can be tested by studying correlations with other observables. In this paper, we consider the extra scalar to be a dark matter (DM) candidate, and investigate DM physics as well as the flavor physics and the LHC physics. The DM relic density and the direct-detection cross section are also dominantly given by the Yukawa couplings, so that we find some explicit correlations between DM physics and the flavor physics. In particular, we find the predictions of the $b to s ll$ anomalies against the direct detection of DM.
We investigate the implications of the latest LHCb measurement of $R_K$ for NP explanations of the $B$ anomalies. The previous data could be explained if the $b to s mu^+ mu^-$ NP is in (I) $C_{9,{rm NP}}^{mumu}$ or (II) $C_{9,{rm NP}}^{mumu} = -C_{10,{rm NP}}^{mumu}$, with scenario (I) providing a better explanation than scenario (II). This continues to hold with the new measurement of $R_K$. However, for both scenarios, this measurement leads to a slight tension of $O(1sigma)$ between separate fits to the $b to s mu^+ mu^-$ and $R_{K^{(*)}}$ data. In this paper, we investigate whether this tension can be alleviated with the addition of NP in $b to s e^+ e^-$. In particular, we examine the effect of adding such NP to scenarios (I) and (II). We find several scenarios in which this leads to improvements in the fits. $Z$ and LQ models with contributions to both $b to s mu^+ mu^-$ and $b to s e^+ e^-$ can reproduce the data, but only within scenarios based on (II). If the tension persists in future measurements, it may be necessary to consider NP models with more than one particle contributing to $b to s ell^+ ell^-$.
One of the fundamental predictions of the Standard Model is Lepton Flavour Universality. Any deviation from this prediction would indicate the existence of physics beyond the Standard Model. Recent LHCb measurements present a pattern of deviations from this prediction in rare B-meson decays. While not yet statistically significant (currently $2.2-2.6 sigma$), these measurements show an imbalance in the ratio of B-meson decays to a pair of muons in association with a Kaon and decays to a pair of electrons in association with a Kaon. If the measured deviations are indeed present in nature, new physics may mediate interactions involving a pair of same flavour leptons, a $b$- and an $s$-quark. We present the prospect for a search of new physics in this type of interactions at the LHC, in a process that involves an $s$-quark, and a final state with two leptons and a $b$-jet. The proposed search can improve the sensitivity to new physics in these processes by a factor of four compared to current searches with in the total dataset expected at the LHC.
We sketch a novel method to search for light di-leptonic resonances by exploiting precision measurements of Drell-Yan production. Motivated by the recent hints of lepton flavour universality violation in $B to K^{ast} ell^+ ell^-$, we illustrate our proposal by studying the case of spin-1 resonances that couple to muons and have masses in the range of a few GeV. We show that the existing LHC data on $pp to Z/gamma^ast to mu^+ mu^-$ put non-trivial constraints on light di-muon resonance interpretations of $B$ decay anomalies in a model-independent fashion. The impact of our proposal on the long-standing discrepancy in the anomalous magnetic moment of the muon is also briefly discussed.
We compute free energies as well as conformal anomalies associated with boundaries for a conformal free scalar field. To that matter, we introduce the family of spaces of the form $mathbb{S}^atimes mathbb{H}^b$, which are conformally related to $mathbb{S}^{a+b}$. For the case of $a=1$, related to the entanglement entropy across $mathbb{S}^{b-1}$, we provide some new explicit computations of entanglement entropies at weak coupling. We then compute the free energy for spaces $mathbb{S}^atimes mathbb{H}^b$ for different values of $a$ and $b$. For spaces $mathbb{S}^{2n+1}times mathbb{H}^{2k}$ we find an exact match with the free energy on $mathbb{S}^{2n+2k+1}$. For $mathbb{H}^{2k+1}$ and $mathbb{S}^{3}times mathbb{H}^{3}$ we find conformal anomalies originating from boundary terms. We also compute the free energy for strongly coupled theories through holography, obtaining similar results.
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