Bounds on the Z\gamma\gamma couplings from HERA
  The possibility of testing trilinear neutral gauge boson couplings in radiative neutral current scattering at HERA is analyzed using a Monte Carlo program that includes the Standard Model at tree level and the anomalous vertices. Acceptance and isolation cuts are applied as well as optimized cuts to enhance the signal from new physics. The bounds on Z\gamma\gamma couplings that can be achieved are not so stringent as present bounds, even for high luminosities, but probe a different kinematical region almost unsensitive to form factors. 
F. Cornet (1), R. Graciani (2) and J.I. Illana (1) ((1) Universidad de   Granada, Spain, (2) U.A.M., Madrid, Spain)