OSQAR Annual Report 2016

In 2016, no OSQAR experimental run has been conducted at the CERN SM18 hall mostly because of the unavailability of cryogenic power to cool down the spare LHC superconducting dipole. Activities have been reoriented and focused in two other directions. In the first one, preparatory phases for the improvement of the sensitivity of the OSQAR-LSW experiment have been pursued. Studies, developments and preliminary tests of short and long Fabry-Perot cavities have been made in collaboration with the ALPS collaboration. The ground vibrations of the SM18 hall have also been thoroughly characterized to prepare the installation of the 20 m long cavity. This preparatory phase will continue in 2017 following the workplan defined in both proposals submitted to funding agencies for 2017-2019 (ANR-DFG and Czech Science Foundation). In the second direction, the analysis of data coming from the 2015 OSQAR-CHASE run dedicated the chameleon afterglow search has been performed. To fully understand some of the results obtained as well as to further improve the sensitivity and the experimental conditions of OSQAR-CHASE, several developments will be implemented prior to the next experimental run planned for 2017.