A5034665552- Quantum Chromodynamics and Particle Interactions
- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Black Holes and Theoretical Physics
- Cold Atom Physics and Bose-Einstein Condensates
- Quantum Mechanics and Applications
- Physics of Superconductivity and Magnetism
- Cosmology and Gravitation Theories
- Nuclear physics research studies
- Quantum, superfluid, helium dynamics
- Quantum Information and Cryptography
- Atomic and Subatomic Physics Research
- Dark Matter and Cosmic Phenomena
- Advanced Thermodynamics and Statistical Mechanics
- Neutrino Physics Research
- Theoretical and Computational Physics
- Radioactive Decay and Measurement Techniques
- Atomic and Molecular Physics
- Quantum chaos and dynamical systems
- Particle accelerators and beam dynamics
- Advanced NMR Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- High-pressure geophysics and materials
- Pulsars and Gravitational Waves Research
- Radiation Therapy and Dosimetry
Jan Kochanowski University
2016-2025
Goethe University Frankfurt
2016-2025
Instituto de Física Teórica
2011-2025
Institute of Physics
2016-2024
Goethe Institute
2009-2024
Universidad de Salamanca
2018
Kielce University of Technology
2016
Joint Institute for Nuclear Research
2016
University Hospital Frankfurt
2013
Universidad Nacional de La Plata
2012
We study scalar, pseudoscalar, vector, and axial-vector mesons with non-strange strange quantum numbers in the framework of a linear sigma model global chiral $U(N_f)_L \times U(N_f)_R$ symmetry. perform fit meson masses, decay widths, as well amplitudes. The quality is, for hadronic that does not consider isospin-breaking effects, surprisingly good. also investigate question whether scalar $\bar{q}q$ states lie below or above 1 GeV find to be preferred states. Additionally, we describe resonances
We present a two-flavor linear sigma model with global chiral symmetry and vector axial-vector mesons. calculate $\ensuremath{\pi}\ensuremath{\pi}$ scattering lengths the decay widths of scalar, vector, It is demonstrated that meson degrees freedom play an important role in these low-energy processes reasonable theoretical description requires globally chirally invariant terms other than vector-meson mass term. An question for vacuum phenomenology quark content physical scalar ${f}_{0}(600)$...
We study the three-flavor chirally and dilatation invariant extended linear sigma model with (pseudo)scalar (axial-)vector mesons as well a scalar dilaton field whose excitations are interpreted glueball. The successfully describes masses decay widths of quark-antiquark in low-energy region up to 1.6 GeV. Here we detail vacuum properties scalar-isoscalar ${J}^{PC}={0}^{++}$ channel find that (i) narrow glueball is only possible if expectation value (at tree level) quite large (i.e. larger...
When the quark masses are lighter than those in QCD, standard lore is that a chiral transition of first order must emerge for three light flavors. Recently, however, numerical simulations on lattice suggest second limit. Using an extended linear sigma model mean field approximation, we study relation between terms which break anomalous, <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi>U</a:mi><a:mo stretchy="false">(</a:mo><a:mn>1</a:mn><a:msub><a:mo...
We study the strong and electromagnetic decay properties of scalar mesons above 1 GeV within a chiral approach. The scalar-isoscalar states are treated as mixed quarkonia glueball configurations. A fit to experimental mass rates listed by Particle Data Group is performed extract phenomenological constraints on nature resonances issue decays. comparison other results theoretical approaches in meson sector discussed.
We investigate a linear sigma model with global chiral $U(2)_{R} \times U(2)_{L}$ symmetry. The mesonic degrees of freedom are the standard scalar and pseudoscalar mesons vector axial-vector mesons. baryonic nucleon, $N$, its partner, $N^{*}$, which is usually identified N(1535). partner incorporated in so-called mirror assignment, where nucleon mass not solely generated by condensate but also chirally invariant term, $m_{0}$. presence (axial-) fields modifies expressions for axial coupling...
We present a two-flavor linear sigma model with global chiral symmetry and (axial-)vector mesons as well an additional glueball degree of freedom. study the structure well-established scalar resonances ${f}_{0}(1370)$ ${f}_{0}(1500)$: by fit to experimentally known decay widths we find that is predominantly $\overline{q}q$ state ${f}_{0}(1500)$ state. The overall phenomenology these two can be described. Other assignments for our mixed quarkonium-glueball states are also tested, but turn out...
A chiral invariant Lagrangian describing the tetraquark-quarkonia interaction is considered at leading and subleading order in large-${N}_{c}$ expansion. Spontaneous symmetry breaking generates mixing of scalar tetraquark quarkonia states nonvanishing condensates. In particular, strength related to decay strengths into pseudoscalar mesons. The results show that below 1 GeV are mainly four-quark scalars between 2 quark-antiquark states, probably mixed with glueball isoscalar sector.
We study a chiral Lagrangian that describes the two- and three-body decays of pseudoscalar glueball into scalar mesons. The various branching ratios are parameter-free prediction our approach. compute decay channels for with mass 2.6 GeV, as predicted by lattice QCD in quenched approximation, which is reach PANDA experiment at upcoming Facility Antiproton Ion Research. For completeness, we also repeat calculation 2.37 GeV corresponds to resonance $X(2370)$ measured BESIII experiment.
In this paper we present a novel method to extract information on hadron-hadron interactions using for the first time femtoscopic data constrain low-energy constants of QCD effective Lagrangian. This offers new way investigate nonperturbative regime in sectors where scattering experiments are not feasible, such as multistrange and charm ones. As an example its application, use very precise <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:msup><a:mrow><a:mi...
In this work we study the spectral functions of scalar mesons in one- and two-channel cases by using nonlocal interaction Lagrangian(s). When propagators satisfy K\"allen-Lehman representation, a normalized function is obtained, allowing one to take into account finite-width effects evaluation decay rates. one-channel case, suitable light $\ensuremath{\sigma}$ $k$ mesons, can deviate consistently from Breit-Wigner shape. case with subthreshold channel, evaluated well approximated Flatt\'e...
The by now well-established scalar-isoscalar resonance ${f}_{0}(500)$ (the $\ensuremath{\sigma}$ meson) seems potentially relevant in the evaluation of thermodynamic quantities a hadronic gas since its mass is low. However, we recall that contribution to isospin-averaged observables is, surprising accuracy, canceled repulsion from pion-pion scalar-isotensor channel. As result, practice one should not incorporate standard resonance-gas models for studies quantities. In our analysis use...
Light scalar hadrons can be understood as dynamically generated resonances. These arise `companion poles' in the propagators of quark-antiquark seed states when accounting for meson-loop contributions to self-energies latter. Along this line, we extend previous calculations T\"ornqvist and Roos Boglione Pennington, where resonance $a_{0}(980)$ appears companion pole propagator $a_{0}(1450)$ which is predominantly a state. We also construct an effective Lagrangian couples pseudoscalar mesons...
We study the light scalar sector up to $1.8$ GeV by using a quantum field theoretical approach which includes single kaonic state in Lagrangian with both derivative and non-derivative interactions. By performing fit $πK$ phase shift data $I=1/2,$ $J=0$ channel, we show that $K_{0}^{\ast}(800)$ (or $κ$) emerges as dynamically generated companion pole of $K_{0}^{\ast }(1430)$. This is result investigating fluctuations one kaon pion circulating loops dressing $K_{0}^{\ast}(1430)$. determine...
An excess of charged versus neutral kaons has been recently reported by the NA61/SHINE collaboration. Similar excesses were also present in previous experiments, even if with larger errors. Models for hadron productions heavy ion collisions systematically underestimate measured charge-toneutral kaon ratio. In this report, we comment on role charge-symmetry as a specific isospin transformation. particular, show that ensemble initial colliding nuclei being charge-symmetric is sufficient...
We demonstrate how chiral oscillations of a massive Dirac field can be described within quantum theory using finite-time interaction picture approach, where the mass term in Lagrangian is treated as perturbative coupling between massless fields definite chirality. derive formula for at fourth order expansion, obtaining result consistent with derived by means other methods. Furthermore, we illustrate framework effectively describe production processes an electron must exhibit both left...
The study of two-pseudoscalar and two-photon decays for the scalar meson nonet below 1 GeV is performed within an effective approach in which resonances are described as (Jaffe's) tetraquark states. dominant (fall apart decay) subdominant (one transverse gluon intermediate state) decay amplitudes systematically taken into account. latter improves agreement with experimental data. Possible scenarios concerning scalar-isoscalar mixing discussed.
The strong and electromagnetic decays of the ground-state tensor mesons are studied in an effective field approach. A fit to well-known experimental data is performed. decay ratios glueball evaluated possible candidates discussed.
We analyze the mixing of scalar glueball with scalar-isoscalar quarkonia states above 1 GeV in a nonlocal covariant constituent approach. Similarities and differences to point-particle Klein-Gordon limit quantum mechanical case are elaborated. Model predictions for two-photon decay rates scheme indicated.