Conveners
Plenary Session
- James Ritman (Forschungszentrum Jülich)
Plenary Session
- Aleksandra Wrońska (Jagiellonian University)
Plenary Session
- Antoni Szczurek (Institute of Nuclear Physics PAS)
Plenary Session
- Joachim Stroth (Goethe University Frankfurt)
Plenary Session
- Catalina Curceanu (INFN - LNF Frascati)
Plenary Session
- Piotr Salabura (Jagiellonian University)
Plenary Session
- Akira Ohnishi (Kyoto University)
Plenary Session
- Stefan Leupold (Uppsala University)
The Belle II experiment at the SuperKEKB energy-asymmetric $e^+ e^-$ collider is an upgrade of the B factory facility at KEK in Tsukuba, Japan. The experiment began operation in 2019 and aims to record a factor of 50 times more data than its predecessor. Belle II is uniquely capable of studying the so-called "XYZ" particles: heavy exotic hadrons consisting of more than three quarks. First...
Exotic hadrons, which are composed of more than three valence quarks, can provide new insights into the internal structure and dynamics of hadrons, thus improving our knowledge of the non-perturbative regime of QCD. The data collected by the LHCb experiment provides unique opportunities for precise measurement of properties of established exotic hadrons and search for new ones. This talk...
The BESIII experiment at the electron-positron collider BEPCII in Beijing, China is studying e+e- annihilations at center-of-mass energies up to 4.6 GeV. This offers excellent opportunities for a broad physics program. In this talk recent achievements of the collaboration will be discussed, highlighting in particular the precise investigation of the spectrum and decay properties of hadrons in...
A variety of unexpected states have been discovered in the charmonium sector since the beginning of the millennium. Some of them are charged and thus manifestly exotic states. Even though meanwhile confirmed in various different experiments, especially the e+e- experiments have largely contributed to this exciting field of charmonium-like (exotic) XYZ states. An overview of selected results...
Since the turn of the century a large number of states was established experimentally in the quarkonium mass range, most of which do not fit into the scheme provided by the until then for the doubly heavy sector very successful quark model. I will discuss current proposals for the structure of these so called XYZ states with special emphasis on possible experimental signatures that would allow...
In this talk I will give an overview on recent results on the spectrum and properties of
conventional and exotic mesons (glueballs, tetraquarks) as obtained in the framework of
Dyson-Schwinger and Bethe-Salpeter equations. I will discuss the spectrum of (quenched)
glueballs with focus on the comparison with results from lattice gauge theory. For
four-quark systems I will summarize...
Hadron spectroscopy is a valuable tool to experimentally investigate the low-energy, non-perturbative QCD regime, corresponding to the dominant manifestation of the strong force in Nature, in terms of hadrons that constitute the bulk of the visible mass of the Universe. In particular, the measurement of the mesons spectrum, searching for exotic states not compatible with the Quark Model,...
Recently there have been dramatic advancements in accelerator technologies, detection techniques and on the theoretical side, algorithms for first-principle QCD analyses. These have led to several candidates for possible "exotic" hadrons, i.e., multiquark states or quark-gluon hybrids. It thus appears that interpretating the entire hadron spectrum in terms of the most naive constituent quark...
The electromagnetic transition form factors (TFFs) of the light mesons provide a unique laboratory to test fundamental aspects of hadron physics. The TFF describes the coupling between the meson and photons and hence provides a probe of the intrinsic electromagnetic structure of the meson. High statistics measurements of pseudoscalar meson TFFs also play a role for the precision frontier of...
A major goal of the High Acceptance Di-Electron experiment (HADES) [1] at GSI is to study the electromagnetic properties of hadronic matter in the 1-3.5 GeV/nucleon incident energy range. Its excellent particle identification capabilities allowed for a systematic investigation of dielectron, strange particles and pion production in pion, proton, deuteron or heavy-ion induced reactions on...
In this talk, we review recent advances in $\eta$ and $\eta'$ physics allowing to test the Standard Model and extract fundamental parameters such as quark mass ratios. We will focus on processes where final state interactions play a crucial role such as $\eta \to 3 \pi$ or $\eta' \to \eta \pi \pi$.
At VEPP-2000 electron-positron collider in Novosibirsk
the experiments with CMD-3 and SND detectors are performed.
Recent results of hadronic cross section measurements are presented.
KLOE-2 experiment is a successor of KLOE, continuing and extending the broad physics program. In hadron physics, this includes search for a signal from dark mediators, $\gamma\gamma$-processes, and measurement of meson properties. Recent results on progress in $\gamma\gamma$ studies, decays of $\eta$ meson in $\pi^+\pi^-$ and $\pi^0\gamma\gamma$ channels and searches for leptophobic dark boson...
We present a data-driven analysis of the resonant S-wave $\pi\pi \to \pi\pi$ and $\pi K \to \pi K$ reactions using the partial-wave dispersion relation. The contributions from the left-hand cuts are accounted for in a model-independent way using the Taylor expansion in a suitably constructed conformal variable. The fits are performed to experimental and lattice data as well as Roy analyses....
We evaluated recent CLAS Collaboration measurements for the 90 deg meson photoproduction off the nucleon using a tagged photon beam spanning the energy interval s = 3 - 11 GeV^2. The results are compared with the Quark Counting Rules (QCR). predictions. Since Sudakov form factor is absent in the case of photoproduction these processes allows a better check/study of the QCR.
We present results on the measurement of transverse momentum spectra, integrated yields, and angular distributions for light flavor hadrons with a focus on meson production in pp, p-Pb, Xe-Xe, and Pb-Pb collisions. Resonance particles with very short lifetimes probe the rescattering and regeneration processes in the hadronic phase of the system produced in high-energy collisions. The...
The HADES experiment at the GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany
is measuring systematicly hadron properties in $\pi$+A, p+A and A+A collisions at energies of a few GeV.
The versatility of HADES allows to address the medium-modifications of hadrons with a huge variety of different observables: ranging from direct line-shape modifications via the dilepton decay,...
The Functional Renormalization Group (FRG) can be used to calculate spectral functions from analytically continued FRG flow equations for two-point correlation functions. Here we report on the current status of applying this aFRG framework to the calculation of vector and axial-vector meson spectral functions in effective hadronic theories at finite temperature and density. Their medium...
In this talk I shall review how the S-matrix formalism can be applied to study the thermal properties of interacting hadrons.
The central idea of this approach is to compute an effective density of state from the scattering phase shifts.
As the phase shifts encode a wealth of information on the hadronic interactions, e.g. the resonance widths and masses,
the method can robustly handle...
This talk will give a short overview of recent experimental progress in using meson as probes to study nuclear matter effects, such as the probes of initial cold nuclear matter effects and the intermediate hot and dense nuclear medium in proton-ion and ion-ion collisions at LHC. If no dedicated talks on ultra-peripheral collisions (UPC) in the conference, recent meson production results in UPC...
Exploring the 3 dimensional structure of the nucleon can help to understand several fundamental questions of nature, such as the origin of the nucleon spin and the charge and density distributions inside the nucleon. In QCD, the 3-dimensional structure of the nucleon is described by Wigner functions. However, experimentally momentum and coordinate space have to be assessed independently. The...
The quest for the neutron electric dipole moment (neutron EDM) started more than sixty years ago and is still one of the most important tasks faced by experimental physicists. The reason is that a non-zero value of this observable would break both parity and time reversal symmetries. Such a symmetry violation can help us to explain why the Universe is essentially made of matter and not of...
One of the main problems of modern particle physics is the inability of the Standard Model (SM) of Particle Physics to explain the matter-antimatter asymmetry in the Universe. The pursuit of physics beyond the SM is required and one way to achieve it is to strive for the highest precision in the search for electric dipole moments. Permanent electric dipole moments (EDMs) of particles violate...
Two new extremely high precision measurements of the proton rms charge radius performed in 2010-2013 with muonic hydrogen atom demonstrated up to six standard deviations smaller values than the accepted average from all previous experiments performed with different methods (scattering and atomic spectroscopy) on ordinary hydrogen. This discrepancy triggered the well-known “proton radius...
The investigation of the low-energy strong interaction between antikaons and nucleons is crucial for a better understanding of the QCD in non-perturbative regime, with implications going from the domain of particle and nuclear physics to astrophysics. Precise experimental information on the K$^-$N scattering at the energy threshold can be extracted exploiting kaonic atoms. SIDDHARTA-2, which...
The antikaon-nucleon interaction close to threshold provides crucial information on the interplay between spontaneous and explicit chiral symmetry breaking in low-energy QCD. The unique feature of DAFNE, namely the production of low-energy kaons, as well as J-PARC with its high intensity kaon beam, has led to a series of successfully conducted experiments with light kaonic atoms, which have...
In this talk, we will show how the study of two-particle correlations at small relative momentum can be used to give a direct insight into short-range hadron-hadron strong interactions.
Our experimental knowledge on hadron-hadron interactions is based mostly on scattering data and, in the case of systems with strangeness, the study of exotic atoms and the characterization of hypernuclei. We...
Many of the most intriguing questions in contemporary physics manifest themselves in the nucleon puzzles: despite being known for more than a century, basic properties like its mass, spin, structure, radius and abundance are to this day subjected to intense discussions and research. One approach to shed light on a system one wants to learn more about is to replace one of its building blocks...
Over the last few years the Julich-Bonn-Munich Group has performed
extensive studies of the baryon-baryon interaction involving strange
baryons ($\Lambda$, $\Sigma$, $\Xi$) within chiral effective field theory. An
overview of the achieved results will be presented, with emphasis on
baryon-baryon scattering in the strangeness S=-1 sector. Predictions
for few- and many-body systems...
Hadron-hadron interactions are the basic inputs to discuss hadronic molecules and hadronic nuclei. Flavored hadron interactions, however, are generally difficult to access in standard scattering experiments. Recent research activities on hadron-hadron correlation functions open a systematic way to access flavored hadron interactions such as $\Omega N$, $\Xi N$, $\bar{K}N$ and even $DN$...
This contribution reports on our recently developed microscopic model for an antikaon absorption on two nucleons in nuclear matter [1]. The absorption is described within a meson-exchange picture and the primary $K^-N$ interaction strength is derived from the state-of-the-art chiral coupled channel meson-baryon interaction models. The medium modification of the $K^-N$ scattering amplitudes...
Historically important to build the Standard Model (SM) of particle physics, rare kaon decays are still a privileged tool to look beyond it. Current research focuses mostly on $ K \to \pi \nu \bar{\nu}$ decays which are predicted with good accuracy within the SM and beyond. NA62 is the CERN experiment at the SPS built to study precisely $ K^+ \to \pi^+ \nu \bar{\nu}$ and other rare decays. The...
A lot of progress has recently been made in a field of hadron spectroscopy. Intense photon beams complemented by high-resolution hermetic 4pi detectors, supplied with linearly or circularly polarised photons, polarised nuclear targets and ability to detect recoil nucleon polarisation improved our knowledge on excited nucleon states considerably. Most of the progress has been achieved in N* and...
I will review the relevance and the implications of strangeness production in compact stars. In particular, I will discuss kaon condensation, hyperons’ production, strange quark matter production and Witten’s hypothesis on the absolute stability of strange quark matter. I will also outline which are the most promising ways to tests these possibilities in the next 20 years.
The first PET tomograph based on plastic scintillators was designed and built at the Institute of Physics of the Jagiellonian University. Jagiellonian PET (J-PET) is optimized for the detection of photons originating from positron-electron annihilation. It is a unique research device that allows studying decays of positronium in a whole available phase-space. Moreover, it enables to determine...
Magnetic moments of light charged leptons $(\ell$), the electron and the muon, have figured prominently in the early development and evolution of the Standard Model (SM) of elementary particles and interactions. The magnetic anomaly, $a_{\ell} \equiv (g_{\ell} - 2)/2$, continues to provide unique sensitivity to contributions from virtual heavy particle loops. This coupling typically scales...
The first new experimental results on the anomalous magnetic moment of the muon from Fermilab, published in April 2021, confirm the tension with the Standard Model prediction, now at $4.2\sigma$. The uncertainty in the theory prediction is by far dominated by hadronic effects. I discuss how different important contributions can be made more precise by using rigorous theoretical constraints,...
Dark Matter is currently one of the greatest unsolved mysteries in physics. Our current knowledge is encompassed in the Standard Model (SM) of particle physics. While the SM is phenomenally successful in describing the physics of familiar matter to high precision, it is also known to be incomplete. In particular, new physics must be responsible for the dark matter. This discovery triggered an...
