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تسجيل مستخدم جديدUpdate on the b->s anomalies
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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) $C_{9,{rm NP}}^{mumu} = -C_{1
0,{rm NP}}^{mumu}$, 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 fr
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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
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bb{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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