Silvano Simula

Charmed Pseudoscalar and Vector Mesons: a Comprehensive QCD Sum-Rule View of Their Decay Constants

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

In spite of undeniable similarities of the applied techniques, somewhat different challenges are encountered when extracting, from QCD sum rules derived from two-point correlators…

Mass of the $b$ Quark from QCD Sum Rules for $f_{B_{(s)}}$

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We demonstrate that Borel QCD sum rules for heavy-light currents entail a very strong correlation between the $b$ -quark mass $m_{b}$ and the $B$ -meson decay constant $f_{B},$ that is,…

OPE, Heavy-Quark Mass, and Heavy-Meson Decay Constants from QCD Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We present a sum-rule extraction of the decay constants of heavy-light mesons from the two-point correlator of pseudoscalar currents. To this end, we compare the perturbative expan…

hep-lat2017

Tensor form factor for the $D \to I ¨ (K)$ transitions with Twisted Mass fermions

Vittorio Lubicz, Lorenzo Riggio, Giorgio Salerno +2

We present a preliminary lattice calculation of the $D \to I ¨ $ and $D \to K$ tensor form factors $f_{T} (q^{2})$ as a function of the squared 4-momentum transfer $q^{2}$ . ETMC recently co…

Decay constants of heavy pseudoscalar mesons from QCD sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We revisit the sum-rule extraction of the decay constants of the D, Ds, B, and Bs mesons from the two-point correlator of heavy-light pseudoscalar currents. We use the operator pro…

hep-ph2008

How reliable are bound-state parameters obtained from QCD sum rules?

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We discuss the extraction of ground-state parameters, such as decay constants and form factors, from two- and three-point dispersive sum rules, making use of a quantum-mechanical p…

hep-ph2018

Strong Isospin Breaking in the Decay Constants of Heavy-Light Mesons from Local-Duality QCD Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We explore, by a rather peculiar limit of QCD sum rules subject to a Borel transformation (realized by allowing the related Borel mass parameter to approach infinity), how the smal…

nucl-th2002

Comparison among Hamiltonian light-front formalisms at q+ = 0 and q+ <> 0: space-like elastic form factors of pseudoscalar and vector mesons

Silvano Simula

The electromagnetic elastic form factors of pseudoscalar and vector mesons are analyzed for space-like momentum transfers in terms of relativistic quark models based on the Hamilto…

A lattice QCD perspective on weak decays of b and c quarks Snowmass 2022 White Paper

Peter A. Boyle, Bipasha Chakraborty, Christine T. H. Davies +32

Lattice quantum chromodynamics has proven to be an indispensable method to determine nonperturbative strong contributions to weak decay processes. In this white paper for the Snowm…

nucl-th2000

SU(6) breaking effects in the nucleon elastic electromagnetic form factors

Fabio Cardarelli, Silvano Simula

The effects of SU(6) breaking on the nucleon elastic form factors are investigated within the constituent quark model formulated on the light-front. It is shown that the kinematica…

OPE, charm-quark mass, and decay constants of D and D_s mesons from QCD sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We present a sum-rule extraction of the decay constants of the charmed mesons D and D_s from the two-point correlator of pseudoscalar currents. First, we compare the perturbative e…

Systematic errors of transition form factors extracted by means of light-cone sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

This talk presents results of our study of heavy-to-light transition form factors extracted with the help of light-cone sum rules. We employ a model with scalar particles interacti…

hep-lat2021

Gradient flow scale-setting with $N_{f} = 2 + 1 + 1$ Wilson-clover twisted-mass fermions

Constantia Alexandrou, Simone Bacchio, Georg Bergner +12

We present a determination of the gradient flow scales $w_{0}$ , $t_{0}$ and $t_{0} / w_{0}$ in isosymmetric QCD, making use of the gauge ensembles produced by the Extended Twisted Mas…

Effective Continuum Thresholds for Quark-Hadron Duality in Dispersive Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Modifying the standard approaches to nonperturbative QCD based on Borel-transformed dispersive sum rules by allowing the effective continuum thresholds required for the implementat…

hep-lat2023

Inclusive hadronic decay rate of the $I ¨ $ lepton from lattice QCD

Antonio Evangelista, Roberto Frezzotti, Giuseppe Gagliardi +4

Inclusive hadronic decays of the $I ¨ $ lepton are very interesting from the phenomenological point of view since they give access to the CKM matrix elements $V_{u d}$ and $V_{u s}$ . I…

hep-lat2021

Window contributions to the muon hadronic vacuum polarization with twisted-mass fermions

Davide Giusti, Silvano Simula

We present a lattice calculation of the Euclidean position-space windows contributing to the leading-order hadronic vacuum polarization term of the muon anomalous magnetic moment $…

nucl-th1999

Semi-inclusive electron scattering off the deuteron and the neutron structure functions

Silvano Simula

The detection of slow nucleons in semi-inclusive electron scattering processes off the deuteron, 2H(e, e'N)X, is a very promising tool for the extraction of model-independent infor…

hep-ph2006

Constituent quarks, chiral symmetry, and chiral point of the constituent quark model

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We construct the full axial current of the constituent quarks by a summation of the infinite number of diagrams describing constituent-quark soft interactions. By requiring that th…

Unprejudiced Look at Effective Continuum Thresholds in Borel Dispersive Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Dispersive sum rules constitute long-standing tools for extracting hadron features from QCD. We estimate the systematic uncertainties induced by assuming quark-hadron duality and i…

hep-lat2025

Inclusive semileptonic decays of the $D_{s}$ meson: Lattice QCD confronts experiments

Alessandro De Santis, Antonio Evangelista, Roberto Frezzotti +13

We present the results of a first-principles theoretical study of the inclusive semileptonic decays of the $D_{s}$ meson. We performed a state-of-the-art lattice QCD calculation by…

New UTfit Analysis of the Unitarity Triangle in the Cabibbo-Kobayashi-Maskawa scheme

UTfit Collaboration, Marcella Bona, Marco Ciuchini +14

Flavour mixing and CP violation as measured in weak decays and mixing of neutral mesons are a fundamental tool to test the Standard Model (SM) and to search for new physics. New an…

hep-lat2023

Direct lattice calculation of inclusive hadronic decay rates of the $I ¨ $ lepton

Antonio Evangelista, Roberto Frezzotti, Giuseppe Gagliardi +4

The inclusive hadronic decay-rates of the $I ¨ $ lepton are particularly interesting from the phenomenological point of view since they give access to the CKM matrix elements $V_{ud}…

hep-lat2021

Non-Perturbative Bounds for Semileptonic Decays in Lattice QCD

Matteo Di Carlo, Guido Martinelli, Manuel Naviglio +3

We present a new method aiming at a non-perturbative, model-independent determination of the momentum dependence of the form factors entering semileptonic decays using unitarity an…

hep-ph2016

Heavy-Meson Decay Constants: QCD Sum-Rule Glance at Isospin Breaking

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

QCD sum rules for decay constants of heavy mesons with $u$ or $d$ quark yield for $B$ mesons much less isospin breaking than lattice QCD but good agreement for $D$ mesons.

Inclusive semileptonic $B$ -decays from lattice QCD

Paolo Gambino, Shoji Hashimoto, Sandro MÃ¤chler +5

We present the lattice QCD calculation of inclusive semileptonic $B_{s}$ -meson decays. We follow a recently proposed method, which is based on the extraction of smeared spectral dens…

hep-lat2014

Kaon semileptonic vector form factor with $N_{f} = 2 + 1 + 1$ Twisted Mass fermions

Nuria Carrasco, Paolo Lami, Vittorio Lubicz +4

We investigate the vector form factor relevant for the $K_{ℓ 3}$ semileptonic decay using maximally twisted-mass fermions with 4 dynamical flavours ( $N_{f} = 2 + 1 + 1$ ). Our simulation…

hep-ph2020

Nonintegrable threshold singularities of two-point functions in perturbation theory

Dmitri Melikhov, Silvano Simula

In perturbation theory, the spectral densities of two-point functions develop non-integrable threshold singularities at higher orders. In QCD, such singularities emerge when calcul…

hep-lat2019

The hadronic vacuum polarization contribution to $(g_{I^} ¼ - 2)$ : Lattice QCD+QED calculations

Davide Giusti, Silvano Simula

The anomalous magnetic moment of the muon $a_{I^} ¼$ is one of the most accurate quantities in Particle Physics. The long-standing discrepancy of about $3.7$ standard deviations betwee…

hep-lat2013

$K$ and $D$ oscillations in the Standard Model and its extensions from $N_{f} = 2 + 1 + 1$ Twisted Mass LQCD

Nuria Carrasco, Petros Dimopoulos, Roberto Frezzotti +6

We present the first $N_{f} = 2 + 1 + 1$ results for the matrix elements of the operators describing neutral $K$ and $D$ mixing in the Standard Model and its extensions. The combination of…

hep-ph2000

Soft gluon effects in the extraction of higher twists at large Bjorken x

Silvano Simula

Existing data on the (unpolarised) transverse structure function of the proton are analyzed for large values of the Bjorken variable x. The leading-twist and a phenomenological hig…

hep-ph2026

A Dispersive Look at Rare $B$ -meson Semileptonic Decays

Marco Ciuchini, Marco Fedele, Ayan Paul +5

Rare semileptonic $b \to s$ flavour-changing neutral current transitions provide stringent tests of the Standard Model. Their interpretation is limited by hadronic uncertainties, n…

hep-lat2012

D-meson decay constants and a check of factorization in non-leptonic B-decays

Damir Becirevic, Vittorio Lubicz, Francesco Sanfilippo +2

We compute the vector meson decay constants fD*, fDs* from the simulation of twisted mass QCD on the lattice with Nf = 2 dynamical quarks. When combining their values with the pseu…

Strong Couplings of Charmed Mesons and Quarkonia

Wolfgang Lucha, Dmitri Melikhov, Hagop Sazdjian +1

We extract the strong coupling constants of three mesons, each of which is composed of either two charm quarks or one charm quark and one light (i.e., $u$ , $d$ , or $s$ ) quark, from…

hep-lat2025

Inclusive semileptonic decays of the $D_{s}$ meson: A first-principles lattice QCD calculation

Alessandro De Santis, Antonio Evangelista, Roberto Frezzotti +13

We present the results of a first-principles theoretical study of the inclusive semileptonic decays of the $D_{s}$ meson. We performed a state-of-the-art lattice QCD calculation usin…

hep-ph2000

Comment on "Nucleon elastic form factors and local duality"

Silvano Simula

We comment on the papers "Nucleon elastic form factors and local duality" [Phys. Rev. {\bf D62}, 073008 (2000)] and "Experimental verification of quark-hadron duality" [Phys. Rev.…

hep-lat2014

Review of lattice results concerning low energy particle physics

Sinya Aoki, Yasumichi Aoki, Claude Bernard +25

We review lattice results related to pion, kaon, D- and B-meson physics with the aim of making them easily accessible to the particle physics community. More specifically, we repor…

hep-ph2023

Discriminating $B \to D^{*} ℓ I^½$ form factors via polarization observables and asymmetries

Marco Fedele, Monika Blanke, Andreas Crivellin +4

Form factors are crucial theory input in order to extract $∣ V_{c b} ∣$ from $B \to D^{(*)} ℓ I^½$ decays, to calculate the Standard Model prediction for $R (D^{(*)})$ and to as…

hep-lat2026

First-principle evaluation of inclusive hadronic $I ¨ $ decays in QCD+QED

Matteo Di Carlo, Simone Bacchio, Erik BÃ¤ske +12

We present a strategy to extend lattice calculations of inclusive hadronic $I ¨ $ decays from isosymmetric QCD to QCD+QED. The inclusive decay rate can be related to suitable Euclide…

hep-ph2006

Dispersion representations and anomalous singularities of the triangle diagram

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We discuss dispersion representations for the triangle diagram $F (p_{1}^{2}, p_{2}^{2}, q^{2})$ , the single dispersion representation in $q^{2}$ and the double dispersion representation in $p_1^…

Lattice QCD study of inclusive semileptonic decays of heavy mesons

Paolo Gambino, Shoji Hashimoto, Sandro MÃ¤chler +5

We present an ab initio study of inclusive semileptonic decays of heavy mesons from lattice QCD. Our approach is based on a recently proposed method, that allows one to address the…

LFU ratios in B decays using Lattice QCD and Unitarity

Guido Martinelli, Manuel Naviglio, Silvano Simula +1

We present the results of the application of the unitarity-based Dispersion Matrix approach to semileptonic charged-current $B$ decays. This method allows to achieve a non-perturba…

Systematic errors of bound-state parameters obtained with SVZ sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We study systematic errors of the ground-state parameters obtained by Shifman-Vainshtein-Zakharov (SVZ) sum rules, making use of the harmonic-oscillator potential model as an examp…

QCD Sum Rules for Heavy-Meson Decay Constants: Impact of Renormalization Scale and Scheme

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Within the realm of QCD sum rules, one of the most important areas of application of this nonperturbative approach is the prediction of the decay constants of heavy mesons. However…

Heavy-to-light form factors: sum rules on the light cone and beyond

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We report the first systematic analysis of the off-light-cone effects in sum rules for heavy-to-light form factors. These effects are investigated in a model based on scalar consti…

Systematic errors of bound-state parameters extracted by means of SVZ sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

This talk presents the results of our study of systematic errors of the ground-state parameters obtained by Shifman-Vainshtein-Zakharov (SVZ) sum rules. We use the harmonic-oscilla…

Heavy-Quark Masses and Heavy-Meson Decay Constants from Borel Sum Rules in QCD

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Slight sophistications of the QCD sum-rule formalism may have great impact on the reliability of predicted hadron observables, as exemplified for the case of heavy-meson decay cons…

Precise Ratios of Decay Constants of Vector over Pseudoscalar $B_{(s)}$ Mesons

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

The relative magnitude of the decay constants of the pseudoscalar and vector beauty mesons poses (in contrast to the case of charmed mesons) a long-standing puzzle. We revisit this…

Accurate bottom-quark mass from Borel QCD sum rules for $f_{B}$ and $f_{B_{s}}$

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We prove that Borel QCD sum rules for heavy-light currents yield very strong correlations between the $b$ -quark mass $m_{b}$ and the $B$ -meson decay constant $f_{B}$ , namely, $Î´f_B/f_…

hep-ph2026

Multiple dispersive bounds. II) Sub-threshold branch-cuts

Silvano Simula, Ludovico Vittorio

We apply the strategy proposed in the companion paper [1] for dealing with multiple dispersive bounds, to the case of sub-threshold branch-cuts, which is a topic addressed extensiv…

hep-ph2018

Strong Isospin Breaking in Heavy-Meson Decay Constants: Employing Borelized QCD Sum Rules in Local-Duality Limit

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Applying the QCD sum-rule machinery in the so-called local-duality shape to heavy-light mesons reveals that, as a consequence of the non-zero mass gap between up and down quarks, t…

nucl-th1996

Investigation of the neutron structure function via semi-inclusive deep inelastic electron scattering off the deuteron

Silvano Simula

The production of slow nucleons in semi-inclusive deep inelastic electron scattering off the deuteron is investigated in the region $x \gsim 0.3$ for kinematical conditions accessi…

Decay constants of heavy mesons from QCD sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We present a sum-rule extraction of the decay constants of the D, Ds, B, and Bs mesons from the two-point correlator of heavy-light pseudoscalar currents [1]. Our main emphasis is…

hep-lat2026

Lattice determination of the QCD low-energy constant $ℓ_{7}$

Claudio Bonanno, Gilberto Colangelo, Francesco D'Angelo +8

We provide a non-perturbative determination of the scheme- and scale-independent low-energy constant $ℓ_{7}$ , appearing in the QCD effective chiral Lagrangia…

Towards the computation of inclusive decay rates using lattice QCD

Paolo Gambino, Shoji Hashimoto, Sandro MÃ¤chler +5

We present a non-perturbative computation of inclusive rates of semileptonic decays of heavy mesons from lattice QCD simulations. The calculation is based on the extraction of smea…

nucl-th1999

Relativistic effects on the neutron charge form factor in the constituent quark model

Fabio Cardarelli, Silvano Simula

The neutron charge form factor GEn(Q**2) is investigated within a constituent quark model formulated on the light-front. It is shown that, if the quark initial motion is neglected…

nucl-th2000

Target-mass corrections and the Bloom-Gilman duality of the nucleon structure function

Silvano Simula

The occurrence of the Bloom-Gilman local duality in the low-order moments of the nucleon structure function is investigated for values of the squared four-momentum transfer Q**2 be…

hep-lat2007

Light quark masses and pseudoscalar decay constants from Nf=2 twisted mass QCD

Vittorio Lubicz, Silvano Simula, Cecilia Tarantino

We present the results of the lattice QCD calculation of the average up-down and strange quark masses and of the light meson pseudoscalar decay constants, recently performed with N…

Improved QCD Sum-Rule Approach to Heavy-Meson Decay Constants

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

A visible improvement of the QCD sum-rule framework, achieved only recently by a slightly more sophisticated consideration of the hadron excitations and continuum, is applied to th…

hep-ph2023

Insights on the current semi-leptonic $B$ -decay discrepancies -- and how $B_{s} \to I^¼^{+} I^¼^{-} I^^{3}$ can help

Diego Guadagnoli, Camille Normand, Silvano Simula +1

$B_{s} \to I^¼^{+} I^¼^{-} I^^{3}$ , measured at high $q^{2}$ as a partially reconstructed decay, can probe the origin of the existing discrepancies in semi-leptonic $b \to s$ and $b \to c$ decay…

hep-lat2017

HQE parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses

Paolo Gambino, Aurora Melis, Silvano Simula

We present a new lattice determination of some of the parameters appearing both in the Operator Product Expansion (OPE) analysis of the inclusive semileptonic $B$ -meson decays and…

hep-ph1997

Heavy-quark binding and kinetic energies in heavy-light mesons and the constituent quark model

Silvano Simula

The spin-averaged binding energy and the hyperfine mass splitting of heavy-light mesons are investigated within the constituent quark model as a function of the inverse heavy-quark…

hep-lat2019

Isospin-breaking corrections to the muon magnetic anomaly in Lattice QCD

Davide Giusti, Vittorio Lubicz, Guido Martinelli +2

In this contribution we present a lattice calculation of the leading-order electromagnetic and strong isospin-breaking (IB) corrections to the quark-connected hadronic-vacuum-polar…

$∣ V_{c b} ∣$ , LFU and $S U (3)_{F}$ symmetry breaking in $B_{(s)} \to D_{(s)}^{(*)} ℓ I^½_{ℓ}$ decays using Lattice QCD and Unitarity

Guido Martinelli, Manuel Naviglio, Silvano Simula +1

We present an application of the unitarity-based dispersion matrix (DM) approach to the extraction of the CKM matrix element $∣ V_{c b} ∣$ from the experimental data on the exclusive…

hep-lat2006

SU(3)-breaking effects in hyperon semileptonic decays

Silvano Simula

We present the first quenched lattice QCD study of all the vector and axial form factors relevant for the hyperon semileptonic decay Sigma- -> n l nu.

hep-lat2018

Simulating twisted mass fermions at physical light, strange and charm quark masses

Constantia Alexandrou, Simone Bacchio, Panagiotis Charalambous +11

We present the QCD simulation of the first gauge ensemble of two degenerate light quarks, a strange and a charm quark with all quark masses tuned to their physical values within th…

Heavy-Quark Mass and Heavy-Meson Decay Constants from QCD Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We present a sum-rule extraction of heavy-meson decay constants from the two-point correlator of heavy-light pseudoscalar currents. Our main concern is to control the uncertainties…

hep-ph2023

From $D_{s} \to I^^{3}$ in lattice QCD to $B_{s} \to I^¼ I^¼ I^^{3}$ at high $q^{2}$

Diego Guadagnoli, Camille Normand, Silvano Simula +1

We use a recent lattice determination of the vector and axial $D_{s} \to I^^{3}$ form factors at high squared momentum transfer $q^{2}$ to infer their $B_{s} \to I^^{3}$ counterparts. To this en…

hep-ph2004

Generalized Parton Distributions in the Light-Front Constituent Quark Model

Silvano Simula

The Generalized Parton Distributions (GPDs) of the nucleon are analyzed within the relativistic constituent quark model formulated on the light-front. It is shown that the matrix e…

hep-lat2011

Review of lattice results concerning low energy particle physics

Gilberto Colangelo, Stephan Durr, Andreas Juttner +9

We review lattice results relevant for pion and kaon physics with the aim of making them easily accessible to the particle physics community. Specifically, we review the determinat…

Can one control systematic errors of QCD sum rule predictions for bound states?

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We study the possibility to control systematic errors of the ground-state parameters obtained by Shifman-Vainshtein-Zakharov (SVZ) sum rules, making use of the harmonic-oscillator…

Extraction of bound-state parameters from dispersive sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

The procedure of extracting the ground-state parameters from vacuum-to-vacuum and vacuum-to-hadron correlators within the method of sum rules is considered. The emphasis is laid on…

hep-ph2017

Isospin Breaking in Heavy-Meson Decay Constants

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Evaluation of Borelized QCD sum rules in the so-called local-duality limit of infinitely large Borel mass parameter provides an alternate route for extraction of the dependence of…

hep-ph2026

Multiple dispersive bounds. I) The z-expansion

Silvano Simula, Ludovico Vittorio

We propose the implementation of two ingredients in the phenomenological applications of the unitary approach based on the $z$ -expansion of hadronic form factors, commonly referred…

Accurate decay-constant ratios $f_{B^{}} / f_{B}$ and $f_{B_{s}^{}} / f_{B_{s}}$ from Borel QCD sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We present our analysis of the decay constants of the beauty vector mesons $B^{*}$ and $B_{s}^{*}$ within the framework of dispersive sum rules for the two-point correlator of vector cur…

hep-lat2020

Quark masses and decay constants in $N_{f} = 2 + 1 + 1$ isoQCD with Wilson clover twisted mass fermions

Extended Twisted Mass Collaboration, Georg Bergner, Petros Dimopoulos +8

We present a preliminary study of the pion, kaon and D-meson masses and decay constants in isosymmetric QCD, as well as a preliminary result for the light-quark renormalized mass.…

hep-ph2004

Correspondence between QCD sum rules and constituent quark models

Dmitri Melikhov, Silvano Simula

We compare two widely used approaches to the description of hadron properties: QCD sum rules and constituent quark models. Making use of the dispersion formulation of the quark mod…

hep-lat2018

HVP contribution of the light quarks to the muon $(g - 2)$ including isospin-breaking corrections with Twisted-Mass fermions

Davide Giusti, Vittorio Lubicz, Guido Martinelli +3

We present a preliminary lattice calculation of the leading-order electromagnetic and strong isospin-breaking corrections to the Hadronic Vacuum Polarization (HVP) contribution of…

hep-ph2008

Light-cone expansion of heavy-to-light form factors

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We present the results of our recent systematic study of the light-cone expansion of heavy-to-light transition form factors in a model with scalar constituents [1]. We show that th…

Disconnected contribution to the LO HVP term of muon g-2 from ETMC

Constantia Alexandrou, Simone Bacchio, Petros Dimopoulos +13

We present a lattice determination of the disconnected contributions to the leading-order hadronic vacuum polarization (HVP) to the muon anomalous magnetic moment in the so-called…

Decay constants of the charmed vector mesons $D^{}$ and $D_{s}^{}$ from QCD sum rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We present a sum-rule calculation of the decay constants of the charmed vector mesons $D^{*}$ and $D_{s}^{*}$ from the two-point correlator of vector currents. First, we show that the pe…

hep-ph2020

Form factors for $B \to j_{1} j_{2}$ decays into two currents in QCD

Mikhail A. Ivanov, Dmitri Melikhov, Silvano Simula

We discuss the general properties of the $B$ -meson decay form factors $F (q^{2}, q^{'2})$ , describing $B$ -meson decays induced by two currents, e.g., $B$ -decays into four leptons in the…

Lattice calculation of the R-ratio smeared with Gaussian kernel

Constantia Alexandrou, Simone Bacchio, Alessandro De Santis +15

The ratio $R (E)$ of the cross-sections for $e^{+} e^{-} \to$ hadrons and $e^{+} e^{-} \to I^¼^{+} I^¼^{-}$ is a valuable energy-dependent probe of the hadronic sector of the Standard Model. Moreover,…

hep-ph2024

Unitarity constraints and the dispersive matrix

Guido Martinelli, Silvano Simula, Ludovico Vittorio

We present updated estimates of $∣ V_{c b} ∣$ and $R (D^{(*)})$ based on all the available theoretical and experimental data on semileptonic $B \to D^{(*)} ℓ I^½_{ℓ}$ deca…

Decay Constants of Heavy Pseudoscalar Mesons: Reconciling QCD Sum Rules and Lattice QCD

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Exploiting recently proposed novel improvements of the techniques used for extracting from QCD sum rules pivotal hadron characteristics, including their systematic errors, we succe…

hep-ph2016

Heavy-Meson Decay Constants: Isospin Breaking from QCD Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Compared with lattice QCD, isospin breaking of heavy-meson decay constants from QCD sum rules agrees for $D$ mesons but disagrees (by a factor of four) for $B$ mesons.

hep-lat2017

$D \to I ¨ $ and $D \to K$ semileptonic form factors with $N_{f} = 2 + 1 + 1$ twisted mass fermions

Vittorio Lubicz, Lorenzo Riggio, Giorgio Salerno +2

We present a lattice determination of the vector and scalar form factors of the $D \to I ¨ (K) ℓ I^½$ semileptonic decays, which are relevant for the extraction of the CKM matrix eleme…

hep-ph2017

Decay Constants of the Heavy-Light Mesons $D^{()}$ and $B^{()}$ : Isospin Breaking

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

QCD sum rules are analytic predictions of hadron observables from quantum chromodynamics. In the so-called local-duality limit of their Borel-transformed form, all nonperturbative…

Short \& intermediate distance HVP contributions to muon g-2: SM (lattice) prediction versus $e^{+} e^{-}$ annihilation data

Constantia Alexandrou, Simone Bacchio, Petros Dimopoulos +13

We present new lattice results of the ETM Collaboration, obtained from extensive simulations of lattice QCD with dynamical up, down, strange and charm quarks at physical mass value…

Accurate Bottom-Quark Mass from Borel QCD Sum Rules for the Decay Constants of $B$ and $B_{s}$ Mesons

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We show that in the context of QCD sum rules a strong (anti-) correlation between the $b$ -quark mass $m_{b}$ and the $B$ -meson's decay constant $f_{B}$ emerges: $Î´f_B/f_B\approx -8 Î´…

Decay Constants of Beauty Mesons from QCD Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

Our recently completed analysis of the decay constants of both pseudoscalar and vector beauty mesons reveals that in the bottom-quark sector two specific features of the sum-rule p…

hep-ph2003

Longitudinal structure function of the proton at low momentum transfer and extended constituents

Silvano Simula

Recent data on the (inelastic) Nachtmann moments of the unpolarized proton structure function F2p, obtained at low momentum transfer with the CLAS detector at Jefferson Lab, have b…

hep-ph2018

Local-duality QCD sum rules for strong isospin breaking in the decay constants of heavy-light mesons

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

We discuss the leptonic decay constants of heavy--light mesons by means of Borel QCD sum~rules in the local-duality (LD) limit of infinitely large Borel mass parameter. In this lim…

Quark-Hadron Duality and Effective Continuum Thresholds in Dispersive Sum Rules

Wolfgang Lucha, Dmitri Melikhov, Silvano Simula

A novel procedure for extracting hadron characteristics from QCD sum rules, based on effective continuum thresholds (necessary for the implementation of quark-hadron duality) which…

hep-lat2026

Inclusive $B ˉ_{s} \mapsto X_{s ˉ c} ℓ I^ˉ ½$ decays from lattice QCD: computational strategy and a first physical result

Alessandro De Santis, Antonio Evangelista, Gael Finauri +16

We present a strategy to compute the inclusive decay rate for the process $B ˉ_{s} \mapsto X_{s ˉ c} ℓ I^ˉ ½$ from first principles in lattice QCD. The physical decay rate i…