Conveners
Plenary session: [Light Mesons]
- Johan Bijnens (Lund University)
Plenary session: [Baryon Resonances]
- Martin Hoferichter (University of Bern)
Plenary session: [Finite-volume methods for LQCD]
- Colin Morningstar (Carnegie Mellon University)
Plenary session: [Few-Nucleon Dynamics]
- Dean Lee (Michigan State University)
Plenary session: [Nucleon Structure]
- Ulf-G. Meißner (University of Bonn)
Plenary session: [Special Plenary Session]
- Evgeny Epelbaum (Ruhr University Bochum)
Plenary session: [g-2]
- Balasubramanian Ananthanarayan (Indian Institute of Science)
Plenary session: [Nuclear Physics from Lattice Simulations]
- John Bulava (Ruhr University Bochum)
Plenary session: [BSM Physics]
- Luca Girlanda (University of Salento)
Plenary session: [Light Meson Decay]
- Shuangshi Fang (Institute of High Energy Physics)
Plenary session: [Nucleon Structure]
- Hermann Krebs (Ruhr-Universität Bochum)
The quest for sources of the simultaneous violation of C and CP symmetry was popular in the 1960s and has since been mostly neglected. We revisit the operators that break C and CP for flavor-conserving transitions in both the Standard Model effective field theory and the low-energy effective field theory. Subsequently, we match these quark operators to light-meson physics using chiral...
The chiral symmetry of QCD can be exploited to build an effective field theory, called Chiral Perturbation Theory ($\chi$PT), which allows to describe the interactions of light mesons at low energies, where the standard perturbative expansion in the strong coupling constant $\alpha_s$ is no longer possible.
Verification of the predictions of such models, such as the...
Recent progress in studying nucleon resonances using lattice QCD is presented. Systems involving meson-baryon scattering, such as the Lambda(1405) resonance, and baryon-baryon scattering are discussed.
We review the determination of the low-energy pion-nucleon scattering amplitude using Roy-Steiner equations. In particular, we focus on the extraction of nucleon resonances and address some of the most frequently asked questions regarding our analysis. Finally, we also discuss the phenomenological determination of the pion-nucleon $\sigma$-term, derived in combination with modern precision...
Two-pole structures refer to the fact that two dynamically generated states are located close to each other between two coupled channels and have a mass difference smaller than the sum of their widths. Thus, the two poles overlap in the invariant mass distribution of their decay products, creating the impression that only one state exists. This phenomenon was first noticed for the Lambda(1405)...
The finite-volume Lüscher formalism and its extensions provide a powerful method for extracting scattering amplitudes and resonance properties in lattice QCD calculations. The finite-volume energies used in the approach must satisfy an upper bound, i.e. they must be below the lowest multi-particle threshold not explicitly considered in the derivation. Ignoring this would lead to incorrect...
Studying three hadron dynamics using lattice QCD enables first-principles predictions of various hadronic resonances, including the Roper and the doubly-charmed tetraquark. To achieve this, substantial progress has been made in developing, implementing, and applying theoretical tools that connect finite-volume quantities to infinite-volume amplitudes involving three particles. In this...
In this talk, I will discuss the physics program of the low-energy, high-intensity electron accelerator MESA, currently under construction at the Institute for Nuclear Physics in Mainz. Designed to support a comprehensive physics program, MESA will facilitate three distinct experiments. An external beamline will deliver spin-polarized electrons to the P2 experiment, with the major goal of...
In recent years the use of nuclei has become increasingly relevant for experiments studying fundamental parameters of electroweak interactions. For experimental success, reliable theoretical inputs with well-controlled errors are required. Currently chiral effective field theory is one of the most adept theory fulfilling this requirement. In order to use this theory as a tool for studying...
A central goal of nuclear theory is to comprehensively explain the diverse phenomena and unique characteristics observed in nuclear systems through a microscopic framework. In this framework, nucleons interact with each other via two and many-body effective interactions, and with external electroweak probes via effective current operators. These interactions and currents form the core inputs...
We present a combined analysis of the electromagnetic form factors of the nucleon in the space- and time-like regions using dispersion theory. Our framework provides a consistent description of the experimental data over the full range of momentum transfer, in line with the constraints from analyticity and unitarity. The statistical uncertainties of the extracted form factors are estimated...
The polarizabilities of a composite system such as the proton are elementary structure constants. They describe it’s response to an external electromagnetic (EM) field and quantify the deformation of the charge and magnetization distributions inside the proton caused by the electric or magnetic field, respectively. When studied through the virtual Compton scattering process, the virtuality of...
I shall discuss the past, present and future of this remarkable theory.
I review some developments in chiral dynamics and pose some questions that remain to be answered.
Robustly simulating the nature and dynamics of non-equilibrium matter in extreme conditions of energy and density lies beyond the capabilities of classical computation alone. Toward realizing Feynman’s vision, the remarkable advances in quantum information science and technology during the last thirty years continue to profoundly change how we understand and explore fundamental quantum...
I will review the status of the dispersive approach to the two hadronic contributions (vacuum polarization and light-by-light) to the Muon g-2 and give an update on the current puzzles concerning the HVP.
The anomalous magnetic moment of the muon, also called the muon $g-2$, is a sensitive probe of the Standard Model. Any evidence for a non-zero deficit between experimental measurement and theoretical prediction would be ascribed to contributions from physics beyond the SM. While the latest experimental average displays a tension of 5.1$\sigma$ with the SM estimate as published in a White Paper...
In this talk, I review recent results on hadron interactions in lattice QCD, mainly those obtained by the HAL QCD method. In particular, I consider two hadron systems including strange, charm and bottom quarks such as $H$ dibaryon, $\Omega\Omega$, $\Omega_{ccc}\Omega_{ccc}$, $N\phi$, $NJ/\psi$, and tetra quark states $T_{cc}$ and $T_{bb}$. I emphasize the importance of the two-pion exchange...
Lattice QCD calculations of baryon-baryon scattering will be reviewed. In the last few years, there has been a new generation of calculations with increased focus on controlling systematic uncertainties. I will discuss the challenges and recent developments in these calculations.
This talk discusses recent applications of nuclear lattice simulations using chiral effective field theory. Some of the topics to be discussed are accelerated perturbation theory using wavefunction matching, seeing and measuring nucleonic correlations with the pinhole algorithm, intrinsic shapes, nuclear clustering, thermodynamics, and superfluidity.
In this talk, I will discuss chiral perturbation theory with axions, including the axion potential, axion mass, axionic couplings to photons and nucleons, and so on.
Next-generation neutrinoless double-beta decay (0vbb) experiments aim to discover lepton number violation in order to shed light on the nature of neutrino masses. A non-zero signal would have profound implications by demonstrating the existence of elementary Majorana particles and possibly pointing towards a solution of matter-antimatter asymmetry in the universe. However, the interpretation...
The world’s largest sample of J/psi events accumulated at the BESIII detector offers a unique opportunity to investigate eta and eta' physics via two body J/psi radiative or hadronic decays. In recent years the BESIII experiment has made significant progresses in eta/eta' decays. A selection of recent highlights in light meson spectroscopy at BESIII are reviewed in this report, including...
I will describe our recent effort on the precise calculation of the radiative correction to semileptonic kaon decays that leads to an improved determination of the CKM matrix element Vus and further sharpens the so-called "Cabibbo angle anomaly".
Laser spectroscopy of muonic atoms has been recently used to probe the low-energy properties of the proton and light nuclei with unprecedented precision [1]. In the future, measurements of the Lamb shift in muonic hydrogen and helium isotopes are supposed to improve by up to a factor 5. Furthermore, there is an ongoing effort to perform a first-time measurement of the ground-state hyperfine...
Through the calculation of nucleon matrix elements in the off-forward limit, a wealth of information on the structure of the nucleon can be accessed using lattice QCD. This includes the determination of the electromagnetic form factors, the axial form factors and moments of generalised parton distribution functions, such as the gravitational form factors. Significant progress has been made in...
High precision data in the Low-Q2 regime is crucial for the study of effective theories such as chiral perturbation theory, which collectively remain the best treatment of QCD in the non-perturbative regime. Measurements of the nucleon spin structure functions and their moments provide a very useful means to directly test the predictions of effective theories. The Jefferson Lab community has...
