arXiv subjects

A. S. Bakry

Publications and source records attributed to A. S. Bakry.

8 recordsLinked to original sources

arXiv2023

Strings of diquark-quark (QQ)Q baryon before phase transition

We explore the limit at which the effective baryonic Y-string model of the junction approaches the mesonic stringlike behavior. We calculate and compare the numerical values of the static potential and energy-density correlators of diquark-quark and quark-antiquark configurations. The gauge model is pure Yang-Mills $SU(3)$ lattice gauge theory at coupling $β=6.0$ and finite temperature. The diquark setup is approximated as two quarks confined within a sphere of radius $0.1$ fm. The lattice data of the potential and energy show that the string binding the diquark-quark configuration displays an identical behavior to the quark-antiquark confining string. However, with the temperature increase to a small enough neighborhood of the critical point $T_{c}$, the gluonic similarities between the two systems do not manifest neither at short nor intermediate distance scales $R<1.0$ fm. The comparison between the potential and the second moment of the action-density correlators for both systems shows significant splitting. This suggests that subsisted baryonic decoupled states overlap with the mesonic spectrum. The baryonic junction's model for the potential and the profile returns a good fit to the numerical lattice data of the diquark-quark arrangement. However, near the critical point, the mesonic string displays large deviations compared to fits of the corresponding quark-antiquark data.

hep-lat↗

arXiv2023

Intermediate-Distance String Effects in Wilson Loops\\ via Boundary Action

The density profile of the QCD flux tube is investigated within the framework of the Lüscher-Weisz (LW) string action with two boundary terms. The transverse action profile and potential between static quarks are considered using Wilson's loop overlap formalism at zero temperature in SU(2) Yang-Mills theory. We find the predictions of the LW string matching the lattice data for the width of the energy-density and $Q\bar{Q}$ potential up to a small color-source separation of $R=0.32$\,fm.

hep-th↗

arXiv2023

Boundary action and profile of effective bosonic strings

The mean-square width of the energy profile of bosonic string is calculated considering two boundary terms in the effective action. The perturbative expansion of the Lorentz-invariant boundary terms at the second and the fourth order in the effective action is taken around the free Nambu-Goto string. The calculation are presented for open strings with Dirichlet boundary condition on cylinder.

hep-th↗

arXiv2022

Perturbative width of open rigid strings

We present perturbative calculation of the width of the energy profile of rigid strings up to two loops in D dimensions. The perturbative expansion of the extrinsic curvature term signifying the rigidity/smoothness of the string in Polyakov-Kleinert action is taken around the free Nambu-Goto string. The mean-square width of the string field is derived for open strings with Dirichlet boundary condition. We compare the broadening of the smooth Polyakov-Kleinert string to the lattice Mont-Carlo data of the QCD flux tube just before the deconfinement point and find a good match at the intermediate and large color source separation.

hep-th↗

arXiv2020

Quantum delocalization of strings with boundary action in Yang-Mills theory

The width of the quantum delocalization of the QCD strings is investigated in effective string models beyond free Nambu-Goto approximation. We consider two Lorentzian-invariant boundary-terms in the Lüscher-Weisz string action in addition to self-interaction term equivalent to two loop order in the (NG) string action. The geometrical terms which realize the possible rigidity of the QCD string is scrutinized as well. We perform the numerical analysis on the 4-dim pure $SU(3)$ Yang-Mills lattice gauge theory at two temperature scales near deconfinement point. The comparative study with this QCD string model targets the width of the energy profile of a static quark-antiquark system for color sources separation $0.5 \le R \le 1.2$ fm. We find the inclusion of rigidity properties and symmetry effects of the boundary action into the string paradigm to reproduce a good match with the profile of the Mont-Carlo data of QCD flux-tube on this distance scale.

hep-lat↗

arXiv2020

On QCD strings beyond non-interacting model

We investigate the implications of Nambu-Goto (NG), Lüscher-Weisz (LW) and Polyakov-Kleinert (PK) string actions for the Casimir energy of the QCD flux-tube at one and two loop order at finite temperature. We perform our numerical study on the 4-dim pure SU(3) Yang-Mills lattice gauge theory at finite temperature $β=6.0$. The static quark-antiquark potential is calculated using link-integrated Polyakov loop correlators. At a high temperature-close to the critical point- We find that the rigidity and self-interactions effects of the QCD string to become detectable. The remarkable feature of this model is that it retrieves a correct dependency of the renormalized string tension on the temperature. Good fit to static potential data at source separations $R \ge 0.5$ fm is obtained when including additional two-boundary terms of (LW) action. On the other-hand, at a lower temperature-near the QCD plateau- We detect signatures of two boundary terms of the Lüscher-Weisz (LW) string action. The (LW) string with boundary action is yielding a static potential which is in a good agreement with the lattice data, however, for color source separation as short as $R=0.3$ fm.

hep-lat↗

arXiv2015

Non-monopole magnetic solutions in the Weinberg-Salam model

The structure of finite energy non-monopole solutions with azimuthal magnetic flux of topological origin is studied in the pure bosonic sector of the Weinberg-Salam model. Applying a variational method we have found simple magnetic field configurations which minimize the energy functional and possess energies of order 1 TeV. Such configurations correspond to composite bound states of W, Z and Higgs bosons with essentially less energy in comparison to monopole like particles supposed to be found at LHC.

hep-ph↗

arXiv2010

String effects and the distribution of the glue in mesons at finite temperature

The distribution of the gluon action density in mesonic systems is investigated at finite temperature. The simulations are performed in quenched QCD for two temperatures below the deconfinment phase. Unlike the gluonic profiles displayed at T=0, the action density iso-surfaces display a prolate-spheroid like shape. The curved width profile of the flux-tube is found to be consistent with the prediction of the free Bosonic string model at large distances.

hep-lat↗