Photon and neutral pion reconstruction

The reconstruction of neutral particles is performed by LHCb calorimeters. The photons are reconstructed from neutral clusters in ECAL which are not associated with reconstructed tracks. For precise determination of photon parameters in addition the information from Prs and Spd detectors are used. Neutral pions are reconstructed either from 2 photons (``resolved'' $\pi^0$) or from single cluster in ECAL (``merged'' $\pi^0$). The note describes in detail the reconstruction, energy and position correction techniques and identification procedure for photons, the reconstruction of ``resolved'' $\pi^0$ from pair of photons and the reconstruction of ``merged'' $\pi^0$ from single cluster in ECAL using dedicated iterative techniques.