arXiv subjects

G. Bozkır

Publications and source records attributed to G. Bozkır.

5 recordsLinked to original sources

arXiv2026

Probing the $B^{0}$ meson in a hot medium with finite baryon chemical potential

We perform a quantitative analysis of the $B^{0}$ meson spectroscopic parameters in a hot and dense medium. Within the framework of QCD two-point sum rules, we calculate the mass and decay constant of the $B^{0}$ meson with the help of the perturbative spectral density and nonperturbative contributions up to mass dimension five as functions of temperature $T$ and baryon chemical potential $μ_B$. For various fixed values of the baryon chemical potential, our numerical results indicate that both the mass and decay constant of the $B^{0}$ meson initially increase with temperature, reach a maximum, and then gradually decrease before eventually vanishing at sufficiently high temperatures. The corresponding vanishing points are found to be in the temperature intervals $(0.182-0.273)~\mathrm{GeV}$ and $(0.118-0.173)~\mathrm{GeV}$, for the mass and decay constant, respectively. Moreover, these temperatures move toward lower values as the baryon chemical potential increases. On the other hand, for various fixed temperatures, both the mass and decay constant exhibit a slight initial increase with increasing baryon chemical potential, followed by a subsequent decrease, eventually vanishing at sufficiently high chemical potentials. The vanishing points for the decay constant is determined to be in baryon chemical potential interval $(0.23-0.83)~\mathrm{GeV}$. For the mass, the decrease at $T=0$ is much weaker than at finite temperatures; excluding this case, the vanishing points for the mass are determined to be in baryon chemical potential interval $(0.38-1.43)~\mathrm{GeV}$ for different fixed temperatures. It is further observed that the baryon chemical potential values corresponding to the vanishing of both the mass and decay constant move to lower values as the temperature increases. In the $T \to 0$ and $μ_B \to 0$ limit ...

hep-ph↗

arXiv2026

Kaons in hot and dense QCD

We present a systematic QCD sum-rule analysis of the in-medium properties of the charged kaon doublet $K^{\pm}$ over the full $(T,ρ)$ plane relevant to current and forthcoming heavy-ion experiments. Working within the QCD sum-rule framework and incorporating temperature-and density-dependent quark, gluon, and mixed condensates, we derive Borel-transformed sum rules for the effective masses $m_{K^{\pm}}$, the pseudoscalar decay constants $f_{K^{\pm}}$, and the vector self-energy $Σ_{v}$ of both charged states simultaneously. Our vacuum results, $m_{K^{-}} = 494.6^{+4.9}_{-6.9}$~MeV and $f_{K^{-}} = 157.3^{+4.1}_{-2.9}$~MeV (with near-degenerate $K^{+}$ values), are in excellent agreement with Particle Data Group values at the sub-percent level. In the medium, $m_{K^{\pm}}$ decreases monotonically with increasing baryon density and temperature, signalling progressive partial restoration of chiral symmetry. A pronounced mass splitting $Δm = m_{K^{-}} - m_{K^{+}}$ develops in baryonic matter, driven by the opposite sign of the Weinberg--Tomozawa vector interaction for the two charge states; it reaches $|Δm| \sim 0.35$~GeV near $ρ\simeq 3.2\,ρ_{\rm sat}$ at $T = 0$ and is partially quenched by thermal fluctuations. A central outcome of this study is the extraction of the critical onset density $ρ_c$, defined as the threshold beyond which the in-medium modifications of $K^{-}$ properties signal the onset of the transition toward the chirally restored phase. We stress that $ρ_c(T)$ should not be interpreted as a precise determination of the QCD critical point-a task beyond the reach of any current effective framework-but rather as an indicator ....

hep-ph↗

arXiv2024

Analysis of the resonance X(4630) at non-zero temperature

We calculate the spectroscopic parameters of resonance $X(4630)$ observed in the process $B^{+}\rightarrow J/ΨϕK^{+}$ by at the LHCb experiments at CERN by means of thermal QCD sum rule method at non-zero temperature. The exotic vector $X(4630)$ is assigned as the diquark-antidiquark state $[cs][\overline{cs}]$ with spin-parity $J^{PC}=1^{-+}$. Employing the two-point QCD sum rule approach up to the sixth order of the operator dimension by including non-perturbative contribution, we calculate the mass and decay constant of $X(4630)$ at $T\neq0$. The numerical analyses demonstrate that the values of the mass and decay constant of $X(4630)$ near the deconfinement temperature decrease up to $9.8\%$ and $60\%$ of their vacuum values. At $T\rightarrow0$, the obtained results for the mass $m_{X(4630)}=(4649\pm40)$ MeV and decay constant $λ_{X(4630)}=(10.07\pm0.8)\times10^{-3} $ MeV are in excellent agreement with the results reported by LHCb experiments and other theoretical predictions.

hep-ph↗

arXiv2023

Properties of kaon at non-zero temperature and baryon chemical potential

We investigate the spectroscopic properties of the strange particle kaon in the framework of hot and dense QCD. To this end, first, we find the perturbative spectral density, which is connected with both the temperature $T$ and the baryon chemical potential $μ_{B}$. We include the non-perturbative operators as functions of temperature and baryon chemical potential up to mass dimension five. We perform the calculations in momentum space and use the quark propagator in the hot and dense medium. The numerical results at non-zero temperature and baryon chemical potential demonstrate that the mass of the particle rises considerably by increasing the baryon chemical potential at a fixed temperature (for both the zero and non-zero temperatures) up to approximately $μ_{B}=0.4$ GeV. After this point, it starts to fall by increasing the baryon chemical potential and it apparently vanishes at $μ_{B}=(1.03-1.15)$ GeV for finite temperatures: The point of apparent vanishing moves to lower baryon chemical potentials by increasing the temperature. At zero temperature, the mass reaches to roughly a fixed value at higher baryon chemical potentials. On the other hand, the decay constant decreases considerably with respect to baryon chemical potential up to roughly $μ_{B}=0.4$ GeV, but after this point, it starts to increase in terms of the baryon chemical potential at finite temperatures. At $T=0$, the decay constant reaches to a fixed value at higher chemical potentials, as well. Regarding the dependence on the temperature we observe that, at fixed values of baryon chemical potentials, the mass and decay constant remain roughly unchanged up to $T=50$ MeV and $T=70$ MeV respectively, but after these points, the mass starts to fall and the decay constant starts to rise up to a critical temperature $T=155$ MeV, considerably.

hep-ph↗

arXiv2021

Properties of spin-1/2 heavy baryons at nonzero temperature

The spectroscopic properties of single heavy spin-1/2 $Λ_{Q}$, $Σ_{Q}$, $Ξ^{(\prime)}_{Q}$ and $ Ω_{Q}$ baryons are investigated at finite temperature in the framework of thermal QCD sum rule. We discuss the behavior of the mass and residue of these baryons with respect to temperature taking into account contributions of non-perturbative operators up to dimension eight. We include additional operators coming from the Wilson expansion due to breaking the Lorentz invariance at non-zero temperature. The obtained results show that the mass of these baryons remain stable up to roughly $T=108$ MeV while their residue are unchanged up to $T=93$ MeV. After these points, the mass and residue start to diminish by increasing the temperature. The shifts in the mass and residue for both the bottom and charm channels are considerably large and we observe the melting of these baryons near to the pseudo-critical temperature determined by recent lattice QCD calculations. We present our results for the mass of these baryons with both the positive and negative parity at $ T\rightarrow 0 $ limit, which are consistent with the existing theoretical predictions as well as experimental data.

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