Measurements of the Angular Distributions in the Decays<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>B</mml:mi><mml:mo>→</mml:mo><mml:msup><mml:mi>K</mml:mi><mml:mrow><mml:mo stretchy="false">(</mml:mo><mml:mo>*</mml:mo><mml:mo stretchy="false">)</mml:mo></mml:mrow></mml:msup><mml:msup><mml:mi>μ</mml:mi><mml:mo>+</mml:mo></mml:msup><mml:msup><mml:mi>μ</mml:mi><mml:mo>−</mml:mo></mml:msup></mml:math>at CDF

Self Cite

Abstract:The angular distribution and differential branching fraction of the decay B + → K + µ + µ − are studied with a dataset corresponding to 1.0 fb −1 of integrated luminosity, collected by the LHCb experiment. The angular distribution is measured in bins of dimuon invariant mass squared and found to be consistent with Standard Model expectations. Integrating the differential branching fraction over the full dimuon invariant mass range yields a total branching fraction of B(B + → K + µ + µ − ) = (4.36 ± 0.15 ± 0.18) × 10 −7 . These measurements are the most precise to date of the B + → K + µ + µ − decay.

Section: Discussionsupporting

confidence: 89%

Differential branching fraction and angular analysis of the B + → K + μ + μ − decay

Aaij¹,

Beteta²,

Adametz³

et al. 2013

Self Cite

“…There is also a previous measurement by CDF [46,47] but with a very large uncertainty. One can understand the discriminating power of this observable with the following argument.…”

mentioning

confidence: 87%

On the impact of power corrections in the prediction of B → K *μ+μ− observables

Descotes-Genon

Hofer

Matias

et al. 2014

226

242

Abstract:The recent LHCb angular analysis of the exclusive decay B → K * µ + µ − has indicated significant deviations from the Standard Model expectations. Accurate predictions can be achieved at large K * -meson recoil for an optimised set of observables designed to have no sensitivity to hadronic input in the heavy-quark limit at leading order in α s . However, hadronic uncertainties reappear through non-perturbative Λ QCD /m b power corrections, which must be assessed precisely. In the framework of QCD factorisation we present a systematic method to include factorisable power corrections and point out that their impact on angular observables depends on the scheme chosen to define the soft form factors. Associated uncertainties are found to be under control, contrary to earlier claims in the literature. We also discuss the impact of possible non-factorisable power corrections, including an estimate of charm-loop effects. We provide results for angular observables at large recoil for two different sets of inputs for the form factors, spelling out the different sources of theoretical uncertainties. Finally, we comment on a recent proposal to explain the anomaly in B → K * µ + µ − observables through charm-resonance effects, and we propose strategies to test this proposal identifying observables and kinematic regions where either the charm-loop model can be disentangled from New Physics effects or the two options leave different imprints.

“…The angular distributions of the decay have been studied by the BaBar, Belle, CDF, CMS and LHCb collaborations [1][2][3][4][5][6][7][8][9][10]. The LHCb collaboration has performed the first full angular analysis using the full data sample from Run 1 of the LHC, corresponding to an integrated luminosity of 3 fb −1 [7].…”

Section: Jhep11(2017)176mentioning

confidence: 99%

“…[78]. Neglecting lepton mass effects the CP -averaged S i reduce to the longitudinal polarisation fraction F L = S 1c , the forward-backward asymmetry A FB = 3 4 S 6s and the remaining S 3,4,5,7,8,9 . Additional ratios of S i have been proposed as observables, for which form factor uncertainties cancel at leading order [79,80].…”

Section: Jhep11(2017)176mentioning

confidence: 99%

Direct determination of Wilson coefficients using B0 → K∗0μ+μ− decays

Hurth

Langenbruch²,

Mahmoudi

2017

A method to directly determine the Wilson coefficients for rare b → s transitions using B 0 → K * 0 µ + µ − decays in an unbinned maximum likelihood fit is presented. The method has several advantages compared to the conventional determination of the Wilson coefficients from angular observables that are determined in bins of q 2 , the square of the mass of the dimuon system. The method uses all experimental information in a more efficient way and automatically accounts for experimental correlations. Performing pseudoexperiments, we show the improved sensitivity of the proposed method for the Wilson coefficients. We also demonstrate that it will be possible to use the method with the combined Run 1 and 2 data sample taken by the LHCb experiment.