Bastian Kubis
YOU?
Author Swipe
View article: Improved Standard-Model predictions for $η^{(\prime)}\to \ell^+ \ell^-$
Improved Standard-Model predictions for $η^{(\prime)}\to \ell^+ \ell^-$ Open
The rare decays $η^{(\prime)}\to\ell^+\ell^-$, $\ell\in\{e,μ\}$, are highly suppressed in the Standard Model, both by their chirality structure and the required loop attaching the lepton line to the $η^{(\prime)}\toγ^*γ^*$ matrix element. …
View article: Discovering the $$D_0^*(2100)$$ in B semileptonic decays
Discovering the $$D_0^*(2100)$$ in B semileptonic decays Open
The mass and width of the lightest scalar open-charm state listed in the Review of Particle Physics, the $$D_0^*(2300)$$ , are in puzzling tension with predictions from unitarized chiral perturbation theory (UChPT) and lattice QC…
View article: Advanced parametrisations for hadronic form factors
Advanced parametrisations for hadronic form factors Open
The rich analytic structure of hadronic form factors makes a theoretically consistent yet easily applicable parametrisation cumbersome. Consequently, most parametrisations are limited to reproducing the simplest analytic features sufficien…
View article: Isospin violation effects in the pion-nucleon sigma-term
Isospin violation effects in the pion-nucleon sigma-term Open
View article: Dispersion relations: foundations
Dispersion relations: foundations Open
We give a pedagogical introduction to the founding ideas of dispersion relations in particle physics. Starting from elementary mechanical systems, we show how the physical principle of causality is closely related to the mathematical prope…
View article: Discovering the $D_0^\ast(2100)$ in $B$ semileptonic decays
Discovering the $D_0^\ast(2100)$ in $B$ semileptonic decays Open
The mass and width of the lightest scalar open-charm state listed in the Review of Particle Physics, the $D_0^\ast(2300)$, are in puzzling tension with predictions from unitarized chiral perturbation theory (UChPT) and lattice QCD, which f…
View article: The anomalous magnetic moment of the muon in the Standard Model: an update
The anomalous magnetic moment of the muon in the Standard Model: an update Open
We present the current Standard Model (SM) prediction for the muon anomalous magnetic moment, $a_μ$, updating the first White Paper (WP20) [1]. The pure QED and electroweak contributions have been further consolidated, while hadronic contr…
View article: On the scalar $\pi K$ form factor beyond the elastic region
On the scalar $\pi K$ form factor beyond the elastic region Open
Pion-kaon ( \pi K ) final states, often appearing in heavy-particle decays at the precision frontier, are important for Standard-Model tests, to describe crossed channels with exotic states, and for spectroscopy of excited kaon resonances…
View article: On the scalar $\pi K$ form factor beyond the elastic region
On the scalar $\pi K$ form factor beyond the elastic region Open
Pion-kaon ( \pi K ) final states, often appearing in heavy-particle decays at the precision frontier, are important for Standard-Model tests, to describe crossed channels with exotic states, and for spectroscopy of excited kaon resonan…
View article: Extracting the chiral anomaly from e+e− → 3π
Extracting the chiral anomaly from e+e− → 3π Open
View article: Radiative corrections and Monte Carlo tools for low-energy hadronic cross sections in $e^+ e^-$ collisions
Radiative corrections and Monte Carlo tools for low-energy hadronic cross sections in $e^+ e^-$ collisions Open
We present the results of Phase I of an ongoing review of Monte Carlo tools relevant for low-energy hadronic cross sections. This includes a detailed comparison of Monte Carlo codes for electron–positron scattering into a muon pair, pion p…
View article: Radiative corrections and Monte Carlo tools for low-energy hadronic cross sections in $e^+ e^-$ collisions
Radiative corrections and Monte Carlo tools for low-energy hadronic cross sections in $e^+ e^-$ collisions Open
We present the results of Phase I of an ongoing review of Monte Carlo tools relevant for low-energy hadronic cross sections. This includes a detailed comparison of Monte Carlo codes for electron–positron scattering into a muon pair, pion p…
View article: Model-independent parametrization of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>B</mml:mi><mml:mo stretchy="false">→</mml:mo><mml:mi>π</mml:mi><mml:mi>π</mml:mi><mml:mo>ℓ</mml:mo><mml:mi>ν</mml:mi></mml:math> decays
Model-independent parametrization of decays Open
We introduce a novel parametrization of B→ππℓν form factors relying on partial-wave decompositions and series expansions in suitable variables. We bound the expansion coefficients through unitarity and include left-hand cut contributions u…
View article: Chiral extrapolation of the pion scattering amplitudes and the hadronic vacuum polarization
Chiral extrapolation of the pion scattering amplitudes and the hadronic vacuum polarization Open
View article: Dispersive determination of the $\eta$ and $\eta'$ transition form factors
Dispersive determination of the $\eta$ and $\eta'$ transition form factors Open
View article: Semileptonic $\eta^{(\prime)}$ decays in the Standard Model
Semileptonic $\eta^{(\prime)}$ decays in the Standard Model Open
View article: C and CP violation in effective field theories and applications to η-meson decays
C and CP violation in effective field theories and applications to η-meson decays Open
View article: Roy–Steiner equations for pion–nucleon scattering and nucleon resonances
Roy–Steiner equations for pion–nucleon scattering and nucleon resonances Open
View article: Precision Evaluation of the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>η</mml:mi></mml:math>- and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msup><mml:mrow><mml:mi>η</mml:mi></mml:mrow><mml:mrow><mml:mo>′</mml:mo></mml:mrow></mml:msup></mml:mrow></mml:math>-Pole Contributions to Hadronic Light-by-Light Scattering in the Anomalous Magnetic Moment of the Muon
Precision Evaluation of the - and -Pole Contributions to Hadronic Light-by-Light Scattering in the Anomalous Magnetic Moment of the Muon Open
Next to the π0 pole, η and η′ intermediate states give rise to the leading singularities of the hadronic light-by-light tensor, resulting in sizable contributions to the anomalous magnetic moment of the muon aμ. The strength of the poles i…
View article: Dispersion relation for hadronic light-by-light scattering: η and η′ poles
Dispersion relation for hadronic light-by-light scattering: η and η′ poles Open
A bstract The pseudoscalar-pole contributions to hadronic light-by-light scattering are determined by the respective transition form factors (TFFs) into two virtual photons. These TFFs constitute complicated functions of the photon virtual…
View article: A simple parametrisation of the pion form factor
A simple parametrisation of the pion form factor Open
View article: Dispersion relation for hadronic light-by-light scattering: $η$ and $η'$ poles
Dispersion relation for hadronic light-by-light scattering: $η$ and $η'$ poles Open
The pseudoscalar-pole contributions to hadronic light-by-light scattering are determined by the respective transition form factors (TFFs) into two virtual photons. These TFFs constitute complicated functions of the photon virtualities that…
View article: Polarizabilities from kaon Compton scattering
Polarizabilities from kaon Compton scattering Open
The polarizabilities of light pseudoscalar mesons can be extracted from differential cross sections for Compton scattering near threshold. While this has been accomplished for charged pions employing Primakoff reactions, a corresponding me…
View article: Precision evaluation of the $η$- and $η'$-pole contributions to hadronic light-by-light scattering in the anomalous magnetic moment of the muon
Precision evaluation of the $η$- and $η'$-pole contributions to hadronic light-by-light scattering in the anomalous magnetic moment of the muon Open
Next to the $π^0$ pole, $η$ and $η'$ intermediate states give rise to the leading singularities of the hadronic light-by-light tensor, resulting in sizable contributions to the anomalous magnetic moment of the muon $a_μ$. The strength of t…
View article: Polarizabilities from kaon Compton scattering
Polarizabilities from kaon Compton scattering Open
The polarizabilities of light pseudoscalar mesons can be extracted from differential cross sections for Compton scattering near threshold. While this has been accomplished for charged pions employing Primakoff reactions, a corresponding me…
View article: Anomalous thresholds in B → (P, V)γ* form factors
Anomalous thresholds in B → (P, V)γ* form factors Open
A bstract We study the effects of anomalous thresholds on the non-local form factors describing the hadronization of the light-quark contribution to B → ( P, V ) γ * transitions. Starting from a comprehensive discussion of anomalous thresh…
View article: From pole parameters to line shapes and branching ratios
From pole parameters to line shapes and branching ratios Open
View article: Nucleon resonance parameters from Roy–Steiner equations
Nucleon resonance parameters from Roy–Steiner equations Open
A reliable determination of the pole parameters and residues of nucleon resonances is notoriously challenging, given the required analytic continuation into the complex plane. We provide a comprehensive analysis of such resonance parameter…
View article: Correlations of C and CP violation in η → π0ℓ+ℓ− and η′ → ηℓ+ℓ−
Correlations of C and CP violation in η → π0ℓ+ℓ− and η′ → ηℓ+ℓ− Open
A bstract Based on recent progress in the systematic analysis of C and CP violation in the light-meson sector, we calculate the C -odd transition amplitudes η → π 0 ℓ + ℓ − and η ′ → ηℓ + ℓ − . Focusing on long-distance contributions drive…
View article: Dispersive analysis of the Primakoff reaction $\gamma K\to K\pi$
Dispersive analysis of the Primakoff reaction $\gamma K\to K\pi$ Open
We provide a dispersion-theoretical representation of the reaction amplitudes $\\gamma K\\rightarrow K \\pi$ in all charge channels, based on modern pion--kaon $P$-wave phase shift input. \nCrossed-channel singularities are fixed from phen…