Recent progress in opto-mechanical design of cavity developed for the OSQAR experiment

Two optical methods are used in the laser-based experiment OSQAR at CERN for the search of axions and axion-like particles. The first method looks as light shining through the wall. The second one wants to measure the ultra-fine vacuum magnetic birefringence. Both methods have reached its attainable limits of sensitivity. Present work is focused on increasing the number of photons and their endurance time within the magnetic field using a laser cavity. Presented paper covers recent state of development of a prototype of a 1 meter long laser cavity which is the prerequisite of further development of the experiment.