224 citations · 1.6k across the 72 of their papers we have counts for
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Quark mass functions in Minkowski space
Elmar P. Biernat, Franz Gross, M. T. Peña +1
Using the Covariant Spectator Theory (CST), we calculate the dressed quark mass function and wave-function renormalization for the five quark flavors from up/down to bottom in both…
Five-body systems with Bethe-Salpeter equations
Gernot Eichmann, M. T. Peña, Raul D. Torres
We extend the Bethe-Salpeter formalism to systems made of five valence particles. Restricting ourselves to two-body interactions, we derive the subtraction terms necessary to preve…
Electromagnetic Transition Form Factors of Baryon Resonances
G. Ramalho, M. T. Peña
Recent experimental and theoretical advancements have led to significant progress in our understanding of the electromagnetic structure of nucleons (), nucleon excitations ($N^\…
Heavy baryon spectroscopy in a quark-diquark approach
A. Torcato, A. Arriaga, G. Eichmann +1
We report progress on calculations of the heavy-light baryons and and their excitations with using functional methods. We employ a covariant quark-diquark…
Covariant model for the Dalitz decay of the resonance
G. Ramalho, M. T. Peña
We develop a covariant model for the transition in the timelike kinematical region, the region where the square momentum transfer is positive. Our star…
Hyperon electromagnetic timelike elastic form factors at large
G. Ramalho, M. T. Peña, K. Tsushima
We present estimates of the hyperon elastic form factors for the baryon octet and the baryon for large four-momentum transfer squared, , in the timelike region ()…
Scattering amplitudes and contour deformations
Gernot Eichmann, Pedro Duarte, M. T. Peña +1
We employ a scalar model to exemplify the use of contour deformations when solving Lorentz-invariant integral equations for scattering amplitudes. In particular, we calculate the o…
Quark mass function from a one-gluon-exchange-type interaction in Minkowski space
Elmar P. Biernat, Franz Gross, M. T Peña +2
We present first results for the quark mass function in Minkowski space in both the spacelike and timelike regions calculated from the same quark-antiquark interaction kernel used…
Heavy and heavy-light mesons in the Covariant Spectator Theory
Alfred Stadler, Sofia Leitão, M. T. Peña +1
The masses and vertex functions of heavy and heavy-light mesons, described as quark-antiquark bound states, are calculated with the Covariant Spectator Theory (CST). We use a kerne…
Heavy and heavy-light mesons and the Lorentz structure of the quark-antiquark interaction
Sofia Leitão, Alfred Stadler, M. T. Peña +1
We solve a Minkowski-space integral equation, derived in the Covariant Spectator Theory, for quark-antiquark bound states describing heavy and heavy-light mesons. The equation's ke…
Covariant spectator theory of quark-antiquark bound states: Mass spectra and vertex functions of heavy and heavy-light mesons
Sofia Leitão, Alfred Stadler, M. T. Peña +1
We use the covariant spectator theory with an effective quark-antiquark interaction, containing Lorentz scalar, pseudoscalar, and vector contributions, to calculate the masses and…
Comparison of two Minkowski-space approaches to heavy quarkonia
Sofia Leitão, Yang Li, Pieter Maris +4
In this work we compare mass spectra and decay constants obtained from two recent, independent, and fully relativistic approaches to the quarkonium bound-state problem: the Hamilto…
Relativistic phenomenology of meson spectra with a covariant quark model in Minkowski space
Sofia Leitão, Alfred Stadler, M. T. Peña +1
In this work, we perform a covariant treatment of quark-antiquark systems. We calculate the spectra and wave functions using a formalism based on the Covariant Spectator Theory (CS…
Application of the Covariant Spectator Theory to the study of heavy and heavy-light mesons
Sofia Leitão, Alfred Stadler, M. T. Peña +1
As an application of the Covariant Spectator Theory (CST) we calculate the spectrum of heavy-light and heavy-heavy mesons using covariant versions of a linear confining potential,…
Covariant Spectator Theory of heavy-light and heavy mesons and the predictive power of covariant interaction kernels
Sofia Leitão, Alfred Stadler, M. T. Peña +1
The Covariant Spectator Theory (CST) is used to calculate the mass spectrum and vertex functions of heavy-light and heavy mesons in Minkowski space. The covariant kernel contains L…
Chiral-symmetry breaking and pion structure in the Covariant Spectator Theory
Elmar P. Biernat, M. T. Peña, Franz Gross +2
We introduce a covariant approach in Minkowski space for the description of quarks and mesons that exhibits both chiral-symmetry breaking and confinement. In a simple model for the…
Rôle of the pion electromagnetic form factor in the timelike transition
G. Ramalho, M. T Pena, J. Weil +2
The magnetic dipole form factor () is described here within a new covariant model that combines the valence quark core together with the pion cloud…
Quarkonia and heavy-light mesons in a covariant quark model
Sofia Leitão, Alfred Stadler, M. T. Peña +1
Preliminary calculations using the Covariant Spectator Theory (CST) employed a scalar linear confining interaction and an additional constant vector potential to compute the mesoni…
Quark model with chiral-symmetry breaking and confinement in the Covariant Spectator Theory
Elmar P. Biernat, M. T. Peña, J. E. Ribeiro +2
We propose a model for the quark-antiquark interaction in Minkowski space using the Covariant Spectator Theory. We show that with an equal-weighted scalar-pseudoscalar structure fo…
Chiral-symmetry breaking and confinement in Minkowski space
Elmar P. Biernat, M. T. Peña, J. E. Ribeiro +2
We present a model for the quark-antiquark interaction formulated in Minkowski space using the Covariant Spectator Theory. The quark propagators are dressed with the same kernel th…
A covariant constituent-quark formalism for mesons
S. Leitão, A. Stadler, M. T. Peña +1
Using the framework of the Covariant Spectator Theory (CST) [1] we are developing a covariant model formulated in Minkowski space to study mesonic structure and spectra. Treating m…
Linear confinement in momentum space: singularity-free bound-state equations
Sofia Leitão, Alfred Stadler, M. T. Peña +1
Relativistic equations of Bethe-Salpeter type for hadron structure are most conveniently formulated in momentum space. The presence of confining interactions causes complications b…
Chiral symmetry and pi-pi scattering in the Covariant Spectator Theory
Elmar P. Biernat, M. T. Peña, J. E. Ribeiro +2
The pi-pi scattering amplitude calculated with a model for the quark-antiquark interaction in the framework of the Covariant Spectator Theory (CST) is shown to satisfy the Adler ze…
A covariant model for the reaction
G. Ramalho, M. T. Pena
We apply the covariant spectator quark model to the study of the electromagnetic structure of the state (), an important resonance from the sec…