Schönfeldt, P. Blomley, E. Bründermann, E. Caselle, M. Funkner, S. Hiller, N. Kehrer, B. Müller, A.-S. Nasse, M.J. Niehues, G. Rota, L. Schedler, M. Schuh, M. Weber, M. JACoW Geneva, Switzerland 978-3-95450-182-3 10.18429/JACoW-IPAC2017-MOPAB055 English 227-230 MOPAB055 electron wakefield laser storage-ring radiation Contribution to a conference proceedings 2017 2017-05 http://dx.doi.org/10.18429/JACoW-IPAC2017-MOPAB055 http://jacow.org/ipac2017/papers/mopab055.pdf For electron accelerators, electro-optical methods in the near-field have been shown to be a powerful tool to detect longitudinal bunch profiles. In 2013, we demonstrated for the first time, electro-optical bunch profile measurements in a storage ring at the accelerator test facility and synchrotron light source ANKA at the Karlsruhe Institute of Technology (KIT). To study possible bunch-bunch interactions and its effects on the longitudinal dynamics, these measurements need to be performed in a multi-bunch environment. Up to now, due to long-ranging wake-fields the electro-optical monitoring was limited to single-bunch operation. Here, we present our new in-vacuum setup to overcome this limitation. First measurements show reduced wake-fields in particular around 2 ns, where the subsequent bunch can occur in a multi-bunch environment at ANKA.