Impacts of radiative corrections on measurements of lepton flavour universality in $B\to D\ell {\nu }_{\ell }$ decays

Abstract

Radiative corrections to $B\to D\ell {\nu }_{\ell }$ decays may have an impact on predictions and measurements of the lepton flavour universality observables $\mathcal{R}(D^{+})$ and $\mathcal{R}(D^0)$. In this paper, a comparison between recent calculations of the effect of soft-photon corrections on $\mathcal{R}(D^{+})$ and $\mathcal{R}(D^0)$, and corrections generated by the widely used package PHOTOS is given. The impact of long-distance Coulomb interactions, which are not simulated in PHOTOS, is discussed. Furthermore, the effect of high-energy photon emission is studied through pseudo-experiments in an LHCb-like environment. It is found that over- or underestimating these emissions can cause a bias on $\mathcal{R}(D)$ as high as 7%. However, this bias depends on individual analyses, and future high precision measurements require an accurate evaluation of these QED corrections.

arXiv comment8 pages, 21 figures, published by EPJC

References in corpus (11)

• PYTHIA 6.4 Physics and Manual
• PYTHIA 6.2 Physics and Manual
• A Brief Introduction to PYTHIA 8.1
• Averages of $b$-hadron, $c$-hadron, and $\tau$-lepton properties as of summer 2016
• PHOTOS Monte Carlo: a precision tool for QED corrections in Z and W decays
• Combined analysis of semileptonic $B$ decays to $D$ and $D^{\ast }$: $R(D^{(\ast )})$, $|V_{cb}|$, and new physics
• Revisiting $B\to D\ell \nu$
• Extraction of $|V_{cb}|$ from $B\to D^{(\ast )}\ell {\nu }_{\ell }$ and the Standard Model predictions of $R(D^{(\ast )})$
• Scalar QED, NLO and PHOTOS Monte Carlo
• Soft-Photon Corrections to $\bar{B}\to D{\tau }^{-}{\bar{\nu }}_{\tau }$ Relative to $\bar{B}\to D{\mu }^{-}{\bar{\nu }}_{\mu }$
• Reconstruction of semileptonically decaying beauty hadrons produced in high energy pp collisions

Cited by in corpus (13)

• Semileptonic form factors for $B\to D^{\ast }\ell \nu$ at nonzero recoil from 2 + 1-flavor lattice QCD
• Semitauonic $b$-hadron decays: A lepton flavor universality laboratory
• Measurement of the ratios of branching fractions $\mathcal{R}(D^{\ast })$ and $\mathcal{R}(D^0)$
• QED in $\bar{B}\to \bar{K}{\ell }^{+}{\ell }^{-}$ LFU ratios: Theory versus Experiment, a Monte Carlo Study
• Global fit to $b\to c\tau \nu$ anomalies as of Spring 2024
• D-meson semileptonic decays to pseudoscalars from four-flavor lattice QCD
• Measurement of the shape of the $B_s^0\to D_s^{\ast -}{\mu }^{+}{\nu }_{\mu }$ differential decay rate
• Structure-dependent QED effects in exclusive $B$-meson decays
• Radiative Semileptonic $\bar{B}$ Decays
• $\frac{|V_{ub}|}{|V_{cb}|}$ and Quest for New Physics
• QED factorization of two-body non-leptonic and semi-leptonic $B$ to charm decays
• The QED nonfactorizable correction to the semileptonic charmed three-body $B$ decays
• Standard Model predictions for Lepton Flavour Universality ratios of inclusive semileptonic $B$ decays