Measuring the photo-ionization rate, neutral fraction and mean free path of HI ionizing photons at $4.9 \leq z \leq 6.0$ from a large sample of XShooter and ESI spectra

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We measure the mean free path ($\lambda_{\rm mfp,HI}$), photo-ionization rate ($\langle \Gamma_{\rm HI} \rangle$) and neutral fraction ($\langle f_{\rm HI} \rangle$) of hydrogen in 12 redshift bins at $4.85<z<6.05$ from a large sample of moderate resolution XShooter and ESI QSO absorption spectra.

• The fluctuations in ionizing radiation field are modeled by post-processing simulations from the Sherwood suite using our new code &#34;EXtended reionization based on the Code for Ionization and Temperature Evolution&#34; (EX-CITE).
• EX-CITE uses efficient Octree summation for computing intergalactic medium attenuation and can generate large number of high resolution $\Gamma_{\rm HI}$ fluctuation models.
• Our simulation with EX-CITE shows remarkable agreement with simulations performed with the radiative transfer code Aton and can recover the simulated parameters within $1\sigma$ uncertainty.