Publications (82)
Charm sea effects on charmonium decay constants and heavy meson masses
Salvatore Cali, Kevin Eckert, Jochen Heitger +2
We estimate the effects on the decay constants of charmonium and on heavy meson masses due to the charm quark in the sea. Our goal is to understand whether for these quantities $N_…
Extraction of form factors from lattice QCD
Benoît Blossier, Pierre-Henri Cahue, Jochen Heitger +3
We report on a two-flavour lattice QCD study of the and transitions parameterized, in the heavy quark limit, by the form factors , and $h_{A…
Non-perturbative renormalization of the static axial current in quenched QCD
Jochen Heitger, Martin Kurth, Rainer Sommer
We non-perturbatively calculate the scale dependence of the static axial current in the Schroedinger functional scheme by means of a recursive finite-size scaling technique, taking…
Leptonic D_s decays in two-flavour lattice QCD
Benoit Blossier, Jochen Heitger, Matthias Post
We report on a two-flavour lattice QCD study of the D_s and D_s^* leptonic decays parameterized by the decay constants f_{D_s} and f_{D_s^*}. As the phenomenology in the D_s sector…
Non-perturbative tests of HQET in small-volume quenched QCD
Jochen Heitger, Andreas Juttner, Rainer Sommer +1
We quantitatively investigate the quark mass dependence of current matrix elements and energies, calculated over a wide range of quark masses in the continuum limit of small-volume…
Hadron masses and matrix elements from the QCD Schr"odinger functional
Marco Guagnelli, Jochen Heitger, Rainer Sommer +1
We explain how masses and matrix elements can be computed in lattice QCD using Schr"odinger functional boundary conditions. Numerical results in the quenched approximation demonstr…
Heavy quark masses from lattice QCD
Jochen Heitger
I outline the basic strategies for the computation of charm and bottom quark masses by means of lattice QCD, where particular emphasis is placed on the non-perturbative renormaliza…
Precision coupling from three-flavor lattice QCD
Antoine Gérardin, Jochen Heitger, Simon Kuberski +2
We consider three-flavor QCD and perform a determination of the low-energy coupling of SU(2) Heavy Meson Chiral Perturbation Theory. It is the coupling in the…
Ward identity determination of for lattice QCD in a Schrödinger functional setup
Jochen Heitger, Fabian Joswig, Anastassios Vladikas
We derive chiral Ward identities for lattice QCD with Wilson quarks and flavours, on small lattices with Schrödinger functional boundary conditions and vanis…
First results on the running coupling in QCD with two massless flavours
Achim Bode, Roberto Frezzotti, Bernd Gehrmann +11
We report on the non-perturbative computation of the running coupling of two-flavour QCD in the Schr"odinger functional scheme. The corresponding Lambda-parameter, which describes…
physics from fine lattices
Georg von Hippel, Rainer Sommer, Jochen Heitger +2
We present a preliminary analysis of the charm quark mass and the mass and decay constant of the meson obtained from dynamical simulations of Wilson QCD o…
On improvement of the axial-vector current with stabilised Wilson fermions
Patrick Fritzsch, Jochen Heitger, Justus T. Kuhlmann
We report on the determination of the improvement coefficient for the non-singlet axial-vector current in the framework of stabilised Wilson-Clover fermio…
Towards a non-perturbative matching of HQET and QCD with dynamical light quarks
Michele Della Morte, Patrick Fritzsch, Jochen Heitger +3
We explain how the strategy of solving renormalization problems in HQET non-perturbatively by a matching to QCD in finite volume can be implemented to include dynamical fermions. A…
B meson spectrum and decay constant from Nf=2 simulations
Benoit Blossier, John Bulava, Michele Della Morte +8
We report on the status of an ALPHA Collaboration project to extract quantities for B physics phenomenology from Nf=2 lattice simulations. The framework is Heavy Quark Effective Th…
Applications of non-perturbative renormalization
Jochen Heitger
A short survey of the renormalization problem in QCD and its non-perturbative solution by means of numerical simulations on the lattice is given. Most emphasis is on scale dependen…
Determination of in three-flavour lattice QCD with Wilson fermions and tree-level improved gauge action
John Bulava, Michele Della Morte, Jochen Heitger +1
We report on an ongoing non-perturbative determination of the improvement coefficient of the axial current, , with three flavours of dynamical improved…
Hadronic decay of vector charmonium from the lattice
Benoît Blossier, Jochen Heitger, Jan Neuendorf +1
Estimating decay parameters in lattice simulations is a computationally demanding problem, requiring several volumes and momenta. We explore an alternative approach, where the tran…
On the scaling of the electroweak interface tension at finite temperature
Joachim Hein, Jochen Heitger
We determine the interface tension of the finite-temperature electroweak phase transition in a numerical investigation of the SU(2)--Higgs model on a four-dimensional lattice with…
Towards Precision B-physics from Non-Perturbative Heavy Quark Effective Theory
Michele Della Morte, Jochen Heitger
We convey an idea of the significant recent progress, which opens up good perspectives for high-precision ab-initio computations in heavy flavour physics based on lattice QCD. Rath…
The Schroedinger functional coupling in quenched QCD at low energies
Jochen Heitger, Hubert Simma, Rainer Sommer +1
Existing non-perturbative computations of the running coupling of quenched QCD in the Schroedinger functional scheme are extended to scales mu lying much deeper in the low-energy r…
Non-perturbative improvement and renormalization of the axial current in N_f=3 lattice QCD
John Bulava, Michele Della Morte, Jochen Heitger +1
We report on a non-perturbative computation of the renormalization factor Z_A of the axial vector current in three-flavour O(a) improved lattice QCD with Wilson quarks and tree-lev…
Precision computation of the strange quark's mass in quenched QCD
Joyce Garden, Jochen Heitger, Rainer Sommer +1
We determine the renormalization group invariant quark mass corresponding to the sum of the strange and the average light quark mass in the quenched approximation of QCD, using as…
Non-perturbative determination of c_V, Z_V and Z_S/Z_P in N_f=3 lattice QCD
Jochen Heitger, Fabian Joswig, Anastassios Vladikas +1
We report on non-perturbative computations of the improvement coefficient c_V and the renormalization factor Z_V of the vector current in three-flavour O(a) improved lattice QCD wi…
On the and charmonia leptonic decays
Gabriela Bailas, Benoît Blossier, Jochen Heitger +2
Among the different scenarios of New Physics, those with an extended Higgs sector are examined with a lot of attention. Recent experimental observations of several anomalies in fla…
B-meson spectroscopy in HQET at order 1/m
Fabio Bernardoni, Benoît Blossier, John Bulava +7
We present a study of the B spectrum performed in the framework of Heavy Quark Effective Theory expanded to next-to-leading order in 1/m and non-perturbative in the strong coupling…
The electroweak phase transition at GeV from lattices
Ferenc Csikor, Zoltan Fodor, Jochen Heitger
We study the finite-temperature electroweak phase transition by numerical simulations of the four-dimensional SU(2)-Higgs model on anisotropic lattices with temporal extension $L_t…
improvement of the flavour singlet scalar density in a setup with Wilson fermions
Pia Leonie Jones Petrak, Jochen Heitger, Fabian Joswig
We report on our Ward identity determination of the improvement coefficient for the flavour singlet scalar density, namely , from three-flavour lattic…
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…
Effective heavy-light meson energies in small-volume quenched QCD
Jochen Heitger, Jan Wennekers
We study effective energies of heavy-light meson correlation functions in lattice QCD and a small volume of (0.2 fm)^4 to non-perturbatively calculate their dependence on the heavy…
Field Theoretic Calculation of the Universal Amplitude Ratio of Correlation Lengths in 3D-Ising Systems
Gernot Muenster, Jochen Heitger
In three-dimensional systems of the Ising universality class the ratio of correlation length amplitudes for the high- and low-temperature phases is a universal quantity. Its field…
Non-perturbative improvement of quark mass renormalization in two-flavour lattice QCD
Patrick Fritzsch, Jochen Heitger, Nazario Tantalo
We non-perturbatively determine the renormalization constant and the improvement coefficients relating the renormalized current and subtracted quark mass in O(a) improved two-flavo…
Ratio of flavour non-singlet and singlet scalar density renormalisation parameters in QCD with Wilson quarks
Jochen Heitger, Fabian Joswig, Pia L. J. Petrak +1
We determine non-perturbatively the normalisation factor , where and are the renormalisation parameters of t…
Towards precision heavy flavour physics from lattice QCD
Jochen Heitger
I convey an idea of the significant recent progress, which opens up good perspectives for high-precision ab-initio computations in heavy flavour physics based on lattice QCD. This…
Low energy physics from the QCD Schrödinger functional
Joyce Garden, Marco Guagnelli, Jochen Heitger +2
We review recent work by the ALPHA and UKQCD Collaborations where masses and matrix elements were computed in lattice QCD using Schrödinger functional boundary conditions and wher…
A strategy for B-physics observables in the continuum limit
Alessandro Conigli, Julien Frison, Patrick Fritzsch +7
In a somewhat forgotten paper [1] it was shown how to perform interpolations between relativistic and static computations in order to obtain results for heavy-light observables for…
form factors from lattice QCD with Wilson-clover quarks
Benoît Blossier, Pierre Henri Cahue, Jochen Heitger +3
We report on a two-flavour lattice QCD determination of the and transitions, which in the heavy quark limit can be parameterised by the form factors $\m…
Charm quark mass and D-meson decay constants from two-flavour lattice QCD
Jochen Heitger, Georg M. von Hippel, Stefan Schaefer +1
We present a computation of the charm quark's mass and the leptonic D-meson decay constants f_D and f_{D_s} in two-flavour lattice QCD with non-perturbatively O(a) improved Wilson…
Non-perturbative determination of improvement -coefficients in
Giulia Maria de Divitiis, Maurizio Firrotta, Jochen Heitger +2
We present our preliminary results of the non-perturbative determination of the valence mass dependent coefficients and as well as the ra…
Non-perturbative Heavy Quark Effective Theory: An application to semi-leptonic B-decays
Michele Della Morte, Jochen Heitger, Hubert Simma +1
We review a lattice strategy how to non-perturbatively determine the coefficients in the HQET expansion of all components of the heavy-light axial and vector currents, including 1/…
and in flavour QCD from a combination of continuum limit static and relativistic results
Alessandro Conigli, Julien Frison, Patrick Fritzsch +7
We present preliminary results for B-physics from a combination of non-perturbative results in the static limit with relativistic computations satisfying …
Parameters of Heavy Quark Effective Theory from Nf=2 lattice QCD
Benoit Blossier, Michele Della Morte, Patrick Fritzsch +5
We report on a non-perturbative determination of the parameters of the lattice Heavy Quark Effective Theory (HQET) Lagrangian and of the time component of the heavy-light axial-vec…
Ground-State Extraction of Heavy-Light Meson Semileptonic Decay Form Factors
Antonino D'Anna, Alessandro Conigli, Patrick Fritzsch +7
We discuss the extraction of heavy-light pseudo-scalar to light pseudo-scalar decay form factors from finite time correlation functions. We place particular emphasis on the contami…
Sigma terms of the baryon octet in QCD with Wilson quarks
Pia Leonie Jones Petrak, Gunnar Bali, Sara Collins +3
A lot of progress has been made in the direct determination of nucleon sigma terms. Using similar methods, we consider the sigma terms of the other octet baryons as well. These are…
Leptonic decay constants for D-mesons from 3-flavour CLS ensembles
Sara Collins, Kevin Eckert, Jochen Heitger +2
We report on the status of an ongoing effort by the RQCD and ALPHA Collaborations, aimed at determining leptonic decay constants of charmed mesons. Our analysis is based on large-v…
B-physics from non-perturbatively renormalized HQET in two-flavour lattice QCD
Fabio Bernardoni, Benoit Blossier, John Bulava +7
We report on the ALPHA Collaboration's lattice B-physics programme based on N_f=2 O(a) improved Wilson fermions and HQET, including all NLO effects in the inverse heavy quark mass,…
Comparative Benchmarks of full QCD Algorithms
Roberto Frezzotti, Martin Hasenbusch, Jochen Heitger +2
We report performance benchmarks for several algorithms that we have used to simulate the Schr"odinger functional with two flavors of dynamical quarks. They include hybrid and poly…
Non-perturbative quark mass dependence in the heavy-light sector of two-flavour QCD
Michele Della Morte, Patrick Fritzsch, Jochen Heitger +1
We present preliminary results of the non-perturbative heavy quark mass dependence of heavy-light meson observables in the continuum limit of finite-volume two-flavour lattice QCD.…
Direct access to hadronic decay parameters with twisted boundary conditions
Benoît Blossier, Jochen Heitger, Jan Neuendorf +1
Our exploratory study looks for direct access to the resonant hadronic transition amplitude without resorting to the Lüscher formalism. We study the decay by…
A strategy to compute the b-quark mass with non-perturbative accuracy
Jochen Heitger, Rainer Sommer
We describe a strategy for a non-perturbative computation of the b-quark mass to leading order in 1/m in the Heavy Quark Effective Theory (HQET). The approach avoids the perturbati…
The hadronic decay of vector charmonium
Benoît Blossier, Jochen Heitger, Jan Neuendorf +1
The extraction of decay parameters using lattice techniques is a computationally expensive task, requiring several volumes and group irreps to relate the spectrum on a lattice simu…
M_b and f_B from non-perturbatively renormalized HQET with Nf=2 light quarks
Benoît Blossier, John Bulava, Michele Della Morte +7
We present an updated analysis of the non-perturbatively renormalized b-quark mass and B meson decay constant based on CLS lattices with two dynamical non-perturbatively improved W…
Computation of the strong coupling in QCD with two dynamical flavours
Michele Della Morte, Roberto Frezzotti, Jochen Heitger +3
We present a non-perturbative computation of the running of the coupling alpha_s in QCD with two flavours of dynamical fermions in the Schroedinger functional scheme. We improve ou…
Non-perturbative Heavy Quark Effective Theory
Jochen Heitger, Rainer Sommer
We explain how to perform non-perturbative computations in HQET on the lattice. In particular the problem of the subtraction of power-law divergences is solved by a non-perturbativ…
Non-perturbative renormalization of the static axial current in two-flavour QCD
Michele Della Morte, Patrick Fritzsch, Jochen Heitger
We perform the non-perturbative renormalization of matrix elements of the static-light axial current by a computation of its scale dependence in lattice QCD with two flavours of ma…
Lattice cutoff effects for F_Ds with improved Wilson fermions - a final lesson from the quenched case
Jochen Heitger, Andreas Juttner
In view of the recent excitement about a tension between determinations of f_Ds from experiment and from simulations of lattice QCD with dynamical quarks, we try to clear up the pi…
improved quark mass renormalization for a non-perturbative matching of HQET to three-flavor QCD
Patrick Fritzsch, Jochen Heitger, Simon Kuberski
The use of Heavy Quark Effective Theory (HQET) on the lattice as an approach to B-physics phenomenology is based on a non-perturbative matching of HQET to QCD in finite volume. As…
Matching of heavy-light flavour currents between HQET at order 1/m and QCD: I. Strategy and tree-level study
Michele Della Morte, Samantha Dooling, Jochen Heitger +2
We present a strategy how to match the full set of components of the heavy-light axial and vector currents in Heavy Quark Effective Theory (HQET), up to and including 1/m-correctio…
Non-perturbative determination of Z_A^{stat} in quenched QCD
Jochen Heitger, Martin Kurth, Rainer Sommer
We non-perturbatively calculate the renormalization factor of the static axial vector current in O(a) improved quenched lattice QCD. Its scale dependence is mapped out in the Schro…
Precision renormalisation and improvement of lattice QCD with Wilson fermions
Patrick Fritzsch, Jochen Heitger, Simon Kuberski +2
We renormalise (and improve) the flavour non-singlet axial current, pseudo-scalar density, vector current and tensor current, as well as quark masses, in O(a) improved lattice QCD…
Towards the determination of the charm quark mass on CLS ensembles
Jochen Heitger, Fabian Joswig, Simon Kuberski
We present the current status of our lattice QCD determination of the charm quark mass using dynamical, non-perturbatively improved Wilson fermio…
SSOR preconditioning in simulations of the QCD Schrödinger functional
Marco Guagnelli, Jochen Heitger
We report on a parallelized implementation of SSOR preconditioning for O(a) improved lattice QCD with Schrödinger functional boundary conditions. Numerical simulations in the quen…
The renormalised improved vector current in three-flavour lattice QCD with Wilson quarks
Jochen Heitger, Fabian Joswig
We present the results of a non-perturbative determination of the improvement coefficient and the renormalisation factor , which define the renormalise…
Non-perturbative determination of improvement coefficients b_m and b_A-b_P and normalisation factor Z_m*Z_P/Z_A with N_f=3 Wilson fermions
Giulia Maria de Divitiis, Patrick Fritzsch, Jochen Heitger +3
We determine non-perturbatively the normalisation constant Z_m*Z_P/Z_A as well as the Symanzik coefficients b_m and b_A-b_P, required in O(a) improved quark mass renormalisation wi…
Scaling tests in $\Or(a)$--improved quenched lattice QCD
Jochen Heitger
We present a scaling investigation of renormalized correlation functions in $\Or(a)$--improved quenched lattice QCD. As one observable the renormalized PCAC quark mass is considere…
A non-perturbative computation of the B-meson decay constant and the b-quark mass in HQET
Jochen Heitger
A lattice computation of the B-meson decay constant and the mass of the b-quark to leading order in the heavy quark effective theory is presented. The involved renormalization prob…
Scaling investigation of renormalized correlation functions in O(a) improved quenched lattice QCD
Jochen Heitger
We present a scaling investigation of some correlation functions in $\Or(a)$ improved quenched lattice QCD. In particular, as one observable the renormalized PCAC quark mass is con…
Non-perturbative improvement of the axial current in N_f=3 lattice QCD with Wilson fermions and tree-level improved gauge action
John Bulava, Michele Della Morte, Jochen Heitger +1
The coefficient c_A required for O(a) improvement of the axial current in lattice QCD with N_f=3 flavors of Wilson fermions and the tree-level Symanzik-improved gauge action is det…
and decay constants in QCD with Wilson fermions
Simon Kuberski, Fabian Joswig, Sara Collins +2
We present results for the leptonic decay constants of the D and D mesons from lattice QCD. We employ a set of 49 high statistics gauge ensembles generate…
Non-perturbative renormalization of the axial current in lattice QCD with Wilson fermions and tree-level improved gauge action
John Bulava, Michele Della Morte, Jochen Heitger +1
We non-perturbatively determine the renormalization factor of the axial vector current in lattice QCD with flavors of Wilson-clover fermions and the tree-level Symanzik-imp…
Optimized Distillation Profiles for Heavy-Light Spectroscopy
Jan Neuendorf, Giulia Egbring, Jochen Heitger +4
It has been demonstrated that distillation profiles can be employed to build optimized quarkonium interpolators for spectroscopy calculations in lattice QCD. We test their usefulne…
Non-perturbative renormalization of O(a) improved tensor currents
Leonardo Chimirri, Patrick Fritzsch, Jochen Heitger +4
We present our progress in the non-perturbative O(a) improvement and renormalization of tensor currents in three-flavor lattice QCD with Wilson-clover fermions and tree-level Syman…
Heavy quark masses from step-scaling
Simon Kuberski, Alessandro Conigli, Patrick Fritzsch +6
We present a determination of the charm- and bottom-quark masses using the heavy-quark step-scaling strategy. Renormalization is performed in small volumes where relativistic botto…
Determination of the charm quark mass in lattice QCD with flavours on fine lattices
Jochen Heitger, Fabian Joswig, Simon Kuberski
We present a determination of the charm quark mass in lattice QCD with three active quark flavours. The calculation is based on PCAC masses extracted from flavou…
Effective Chiral Lagrangians and Lattice QCD
Jochen Heitger, Rainer Sommer, Hartmut Wittig
We propose a general method to obtain accurate estimates for some of the "low-energy constants" in the one-loop effective chiral Lagrangian by means of simulating lattice QCD. In p…
from three-flavour lattice QCD
Jochen Heitger, Fabian Joswig, Anastassios Vladikas
We report on advances in the non-perturbative determination of the ratio of the pseudoscalar to the scalar renormalization constants in three-flavour lattice QCD with Wil…
Scaling in the two-dimensional U(1)--Higgs model
Hermann Dilger, Jochen Heitger
We study the continuum limit of the U(1)--Higgs model with variable scalar field length, which is qualitatively different from the fixed length case. Our simulations concentra…
Towards the determination of sigma terms for the baryon octet on CLS ensembles
Pia Leonie Jones Petrak, Gunnar Bali, Sara Collins +4
A lot of progress has been made in the determination of nucleon sigma terms. In this work we consider the sigma terms of the other octet baryons as well. These are determined on CL…
Heavy-strange meson decay constants in the continuum limit of quenched QCD
Michele Della Morte, Stephan Durr, Damiano Guazzini +3
We improve a previous quenched result for heavy-light pseudoscalar meson decay constants with the light quark taken to be the strange quark. A finer lattice resolution (a ~ 0.05 fm…
Non-perturbative tests of Heavy Quark Effective Theory
Jochen Heitger, Andreas Juttner, Rainer Sommer +1
We consider QCD with one massless quark and one heavy quark in a finite volume of linear extent L_0 ~ 0.2 fm. In this situation, HQET represents an expansion in terms of 1/z=1/(m L…
A lattice approach to QCD in the chiral regime
Michele Della Morte, Roberto Frezzotti, Jochen Heitger
Non-perturbative lattice studies of QCD in the chiral thermodynamic regime, where chiral symmetry is spontaneously broken, require to deal with almost quark zero modes in a theoret…
Charmed pseudoscalar decay constants on three-flavour CLS ensembles with open boundaries
Sara Collins, Kevin Eckert, Jochen Heitger +2
We determine the masses and pseudoscalar decay constants of D and D_s mesons employing lattice QCD with non-perturbatively O(a) improved Wilson quarks and a tree-level Symanzik-imp…
Towards charm physics with stabilised Wilson fermions
Patrick Fritzsch, Jochen Heitger, Fabian Joswig +1
We report on a first study towards the use of stabilised Wilson fermions in heavy flavour physics. In particular, we are interested in fixing the charm quark mass via various physi…