Gerhard, P. Barth, W.A. Bevcic, M. Düllmann, Ch.E. Groening, L. Horn, K.P. Jäger, E. Khuyagbaatar, J. Krier, J. Maier, M.T. Scharrer, P. Yakushev, A. JACoW Publishing Geneva, Switzerland 2226-0366 978-3-95450-194-6 10.18429/JACoW-LINAC2018-FR1A05 English 982-987 FR1A05 target operation heavy-ion injection linac Contribution to a conference proceedings 2019 2019-01 https://doi.org/10.18429/JACoW-LINAC2018-FR1A05 http://jacow.org/linac2018/papers/fr1a05.pdf The GSI UNILAC together with SIS18 will serve as injector for the future FAIR. A modified 1.4~MeV/u gas stripper setup has been developed, aiming at an increased yield into the particular desired charge state. The setup delivers short pulses of high gas density in synchronization with the beam pulse. This provides a higher gas density. Different gases as stripping targets were tested. Measurements with various isotopes and gas densities were conducted to investigate the stripping properties. High intensity beams of ²³⁸U⁴⁺ were successfully stripped using hydrogen as stripping gas. The stripping efficiency was significantly increased while the beam quality remained suitable. The new stripper setup and major results achieved during the development are presented. Problems with the fast valves arose while they were used for a longer duration. Another revision of the setup took place to exchange the valves. In parallel, the installation of the required infrastructure for regular operation of the gas stripper using hydrogen was planned.