Spectroscopic characterization of nine binary star systems as well as HIP107136 and HIP107533.

We present the results of our 2nd radial velocity monitoring campaign, carried out with the Echelle spectrograph FLECHAS at the University Observatory Jena in the course of the Grosschwabhausen binary survey between December 2016 and June 2018. The aim of this project is to obtain precise radial velocity measurements for spectroscopic binary stars in order to redetermine, verify, improve and constrain their Keplerian orbital solutions. In this paper we describe the observations, data reduction and analysis and present the results of this project. In total, we have taken 721 RV measurements of 11 stars and derived well determined orbital solutions for 9 systems (7 single-, and 2 double-lined spectroscopic binaries) with periods in the range between 2 and 70 days. In addition, we could rule out the orbital solutions for the previously classified spectroscopic binary systems HIP107136 and HIP107533, whose radial velocities are found to be constant on the km/s-level over a span of time of more than 500 days. In the case of HIP2225 a significant change of its systematic velocity is detected between our individual observing epochs, indicating the presence of an additional companion, which is located on a wider orbit in this system.