Gluon saturation search using direct $\gamma$+hadron correlations in LHCb

Previous DIS results from HERA show a fast increasing of the gluon density in protons towards small Bjorken-$x$ fractional momentum. The size of gluons is inversely proportional to the $Q^2$ momentum transfer of the process. Hence, gluons from processes where $Q^2(x)$ is smaller than $Q_S^2(x)$ are supposed to be saturated. The scale $Q^2_S(x)$ in proton and nucleus are still to be determined experimentally. The LHCb experiment is a single arm detector in LHC with vertexing, tracking, $p$, $K$, $pi$, $e$, $\mu$ identification and calorimetry in the region 1.6$< \eta <$ 4.9, which can access $x \sim 10^{-6}-10^{-4}$, up to two orders of magnitude smaller than HERA. A direct probing of small-$x$ and small $Q^2$ gluons can be performed with direct $\gamma$+hadron correlation measurements. This talk is going to report the status of the analysis efforts aimed of finding evidences of gluon saturation and its scale $Q^2_S(x)$ at LHCb. Future detector improvements in gluon saturation and heavy ion measurements with real-time analysis and a soft particle tracker in LHCb are also going to be discussed.