Magnetic linear birefringence measurements using pulsed fields

In this paper we present the realization of further steps toward the measurement of the magnetic birefringence of a vacuum using pulsed fields. After describing our experiment, we report the calibration of our apparatus using nitrogen gas and discuss the precision of our measurement giving a detailed error budget. Our best present vacuum upper limit is ${Δ}n{{0.16em}{0ex}}{}{{0.16em}{0ex}}5.0{{0.16em}{0ex}}×{}{{0.16em}{0ex}}{10}^{{-}20}T{}^{{-}2}$ per 4 ms acquisition time. We finally discuss the improvements necessary to reach our final goal.