arXiv subjects

Yan F. Ferreira

Publications and source records attributed to Yan F. Ferreira.

5 recordsLinked to original sources

arXiv2026

Non linear Regge trajectories of quarkonia from holography

We propose a holographic model for quarkonia using the WKB approximation with the Langer correction to properly reproduce nonlinear Regge trajectories of the form $m_n^2 = β(n + c_0)^{2/3} + c_1$. This form is expected from previous studies involving the solution of Cornell potential for heavy quark-antiquark interactions using a model based on the quadratic form of the spinless Salpeter-type equation (QSSE). The model fits experimental masses with very good accuracy. The corresponding decay constants also show a reasonable agreement with the results obtained from experimental data.

hep-ph↗

arXiv2025

Holography and the internal structure of charmonium

Holographic models that consider classical vector fields in a 5-d background provide successful effective descriptions for heavy vector meson spectra. This holds both in the vacuum and in a thermal medium, like the quark gluon plasma. However, it is somehow mysterious the way that these phenomenological models work. In particular, what is the role of the fifth dimension and what is the relation between the holographic 5-d background and the physical (4-d) heavy mesons. Hadrons, in contrast to leptons, are composite particles with some internal structure, that depends on the energy at which they are observed. In this work, a static meson is represented by a heavy quark-antiquark pair with an interaction described by a Nambu Goto string living in the same 5-d background that provides field solutions leading to masses and decay constants of charmonium states. The interaction potential that shows up is linear for large distances with a string tension consistent with the effective Cornell potential. Introducing temperature $T$ in the background it is found, for the $J/ψ$ case, that there is a deconfining transition at some critical value of $T$. The results obtained indicate that the 5-d background is effectively representing the internal structure of the (static) charmonium (quasi) states.

hep-ph↗

arXiv2025

Holography and charmonium structure in a finite density plasma

It has recently been proposed that the extra dimension in holographic models for charmoniun is related to its internal structure. Representing the interaction between the quark anti-quark pair by a string inside the background used in these models, the linear term of the Cornell potential was obtained. More than that, the dissociation in the thermal medium is also described in a consistent way. Here we extend this study to the case of a plasma with finite density. The combined effects of density and temperature are analyzed from the point of view of quark anti-quark interaction and the results obtained are consistent with the ones derived previously using spectral functions.

hep-ph↗

arXiv2023

Bottomonium Dissociation in a Rotating Plasma

Heavy vector mesons provide important information about the quark gluon plasma (QGP) formed in heavy ion collisions. This happens because the fraction of quarkonium states that are produced depends on the properties of the medium. The intensity of the dissociation process in a plasma is affected by the temperature, the chemical potential and the presence of magnetic fields. These effects have been studied by many authors in the recent years. Another important factor that can affect the dissociation of heavy mesons, and still lacks of a better understanding, is the rotation of the plasma. Non central collisions form a plasma with angular momentum. Here we use a holographic model to investigate the thermal spectrum of bottomonium quasi-states in a rotating medium in order to describe how a non vanishing angular velocity affects the dissociation process.

hep-ph↗

arXiv2022

Configuration entropy and stability of bottomonium radial excitations in a plasma with magnetic fields

Heavy vector mesons produced in a heavy ion collision are important sources of information about the quark gluon plasma (QGP). For instance, the fraction of bottomonium states observed in such a collision is altered by the dissociation effect caused by the plasma. So, it is very important to understand how the properties of the plasma, like temperature $(T)$, density and the presence of background magnetic fields $(eB)$, affect the dissociation of bottomonium in the thermal medium. AdS/QCD holographic models provide a tool for investigating the properties of heavy mesons inside a thermal medium. The meson states are represented by quasinormal modes in a black hole geometry. In this work we calculate the quasinormal modes and the associated complex frequencies for the four lowest levels of radial excitation of bottomonium inside a plasma with a magnetic field background. We also calculate the differential configuration entropy (DCE) for all these states and investigate how the dissociation effect produced by the magnetic field is translated into a dependence of the DCE on $eB$. An interesting result obtained in this study is that the DCE increases with the radial excitation level $n$. Also, a nontrivial finding of this work is that the energy density associated with the bottomonium quasinormal modes presents a singularity near the black hole horizon for some combination of values of $T, eB$ and $n$. As we show here, it is possible to separate the singular factor and define a square integrable quantity that provides a DCE that is always finite. In addition, we discovered that, working with the potentially singular energy density, one finds a very interesting way to use the DCE as a tool for determining the dissociation temperature of the meson quasisates.

hep-th↗