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The redshift ($z$) evolution of the Extragalactic Background Light (EBL)photon density is very important to understand the history of cosmologicalstructure formation of galaxies and stars since the epoch of recombination. TheEBL photons with the characteristic spectral energy distribution ranging fromultraviolet/optical to far-infrared provide a major source of opacity of theUniverse to the GeV-TeV $\gamma$-rays travelling over cosmological distances.The effect of the EBL is very significant through $\gamma \gamma \rightarrowe^- e^+$ absorption process on the propagation of the $\gamma$-ray photons withenergy $E >$ 50 GeV emitted from the sources at $z \sim 1$. This effect ischaracterized by the optical depth ($\tau$) which strongly depends on $E$, $z$and density of the EBL photons. The proper density of the EBL photons increaseswith $z$ due to expansion of the Universe whereas evolution of radiationsources contributing to the EBL leads to a decrease in the density withincreasing $z$. Therefore, the resultant volumetric evolution of the EBL photondensity is approximated by a modified redshift dependence. In this work, weprobe evolution of the EBL photon density predicted by two prominent modelsusing cosmic gamma-ray horizon ($\tau (E,z)=$ 1) determined by the measurementsfrom the \emph{Fermi}-Large Area Telescope (LAT) observations. The modifiedredshift dependence of the EBL photon density is optimized for a given EBLmodel by estimating the same gamma-ray horizon as predicted by the\emph{Fermi}-LAT observations. We further compare the optical depth estimatesin the energy range $E =$ 4 GeV-1 TeV and redshift range $z =0.01-1$ from the\emph{Fermi}-LAT observations with the values derived from the two EBL modelsto further constrain the evolution of the EBL photon density in the $z~\sim 1$Universe.

Probing the evolution of the EBL photon density out to $z~\sim 1$ via $\gamma$-ray propagation measurements with Fermi