arXiv subjects

G. Kaya

Publications and source records attributed to G. Kaya.

5 recordsLinked to original sources

arXiv2016

Thermal behavior of the mass and residue of hyperons

We investigate the mass and residue of the $Σ$, $Λ$ and $Ξ$ hyperons at finite temperature in the framework of thermal QCD sum rules. In our calculation, we take into account the additional operators coming up at finite temperature. We find the temperature-dependent continuum threshold for each hyperon using the obtained sum rules for their mass and residue. The numerical results demonstrate that the mass and residue of the particles under consideration remain stable up to a certain temperature, after which they decrease by increasing the temperature.

hep-ph↗

arXiv2015

Modifications on nucleon parameters at finite temperature

Taking into account the additional operators coming up at finite temperature, we investigate the mass and residue of the nucleon in the framework of thermal QCD sum rules. We observe that the mass and residue of the nucleon are initially insusceptible to increase of temperature, however after a certain temperature, they start to fall increasing the temperature.

hep-ph↗

arXiv2014

Filament propagation length of femtosecond pulses with different transverse modes

We experimentally studied intense femtosecond pulse filamentation and propagation in water for Gaussian, Laguerre-Gaussian, and Bessel-Gaussian incident beams. These different transverse modes for incident laser pulses were created from an initial Gaussian beam by using a computer generated hologram technique. We found that the length of the filament induced by the Bessel-Gaussian incident beam was longer than that for the other transverse modes under the conditions of the same peak intensity, pulse duration, and the size of the central part of the beam. To better understand the Bessel-Gaussian beam propagation, we performed a more detailed study of the filament length as a function of the number of radial modal lobes. The length increased with the number of lobes, implying that the radial modal lobes serve as an energy reservoir for the filament formed by the central intensity peak.

physics.optics↗

arXiv2012

Spectrum of the heavy axial vector χ_b1(1P) and χ_c1(1P) mesons in thermal QCD

Using the additional operators coming up at finite temperature, we calculate the masses and decay constants of the P wave heavy axial-vector χ_b1 and χ_c1 quarkonia in the framework of thermal QCD sum rules. In the calculations, we take into account the perturbative two loop order alpha_s corrections and nonperturbative effects up to the dimension four condensates. It is observed that the masses and decay constants almost remain unchanged with respect to the variation of the temperature up to T \simeq 100 MeV, however after this point, the decay constants decrease sharply and approach approximately to zero at critical temperature. The decreasing in values of the masses is also considerable after T \simeq 100 MeV .

hep-ph↗

arXiv2011

Thermal QCD Sum Rules Study of Vector Charmonium and Bottomonium States

We calculate the masses and leptonic decay constants of the heavy vector quarkonia, $J/ψ$ and $Υ$ mesons at finite temperature. In particular, considering the thermal spectral density as well as additional operators coming up at finite temperature, the thermal QCD sum rules are acquired. Our numerical calculations demonstrate that the masses and decay constants are insensitive to the variation of temperature up to $T\cong 100 ~MeV$, however after this point, they start to fall altering the temperature. At deconfinement temperature, the decay constants attain roughly to 45% of their vacuum values, while the masses are diminished about 12%, and 2.5% for $J/ψ$ and $Υ$ states, respectively. The obtained results at zero temperature are in good consistency with the existing experimental data as well as predictions of the other nonperturbative models. Considerable decreasing in the values of the decay constants can be considered as a sign of the quark gluon plasma phase transition.

hep-ph↗