Gluon saturation search using photon+hadron correlations in LHCb

Gluon saturation in high-energy collisions is expected to explain several observations in nuclear collisions such as particle collectivity and depleted yields of particle coming from soft gluons. Previous DIS results from HERA show a fast increase of gluons as their fractional momentum x decreases. The size of gluons is inversely proportional to the Q^2 scale of the process. The saturation scale Qs^2(x) is still to be determined experimentally.

The LHCb experiment is a forward spectrometer with vertexing, tracking, p, K, pi, e, mu identification and calorimetry in the region 1.6<eta<4.9. LHCb is the only experiment in the world which can probe x between 1e-6 and 1e-4, up to two orders of magnitude smaller than HERA. A direct probe of gluons can be performed with photon+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 Qs^2(x) at LHCb. Future improvements in these measurements with additional triggers and a soft particle tracker in LHCb are also going to be discussed.