Ostroumov, P.N. Bultman, N.K. Ikegami, M. Lidia, S.M. Lund, S.M. Machicoane, G. Maruta, T. Plastun, A.S. Pozdeyev, G. Rao, X. Wei, J. Wong, C.Y. Xu, T. Yoshimoto, T. Zhao, Q. JACoW Publishing Geneva, Switzerland 978-3-95450-184-7 10.18429/JACoW-IPAC2018-THYGBF4 English 2950-2952 THYGBF4 cavity linac MMI ECR ECRIS Contribution to a conference proceedings 2018 2018-06 https://doi.org/10.18429/JACoW-IPAC2018-THYGBF4 http://jacow.org/ipac2018/papers/thygbf4.pdf This paper presents recent developments of accelerator physics related topics for the Facility for Rare Isotope Beams (FRIB) being built at Michigan State University. While extensive beam dynamics simulations including all known errors do not show uncontrolled beam losses in the linac, ion beam contaminants extracted from the ECR ion source together with main ion beam can produce significant losses after the charge stripper. These studies resulted in development of beam collimation system at relatively low energy of 16 MeV/u and room temperature bunchers instead of originally planned superconducting ones. Commissioning of the Front End enabled detailed beam physics studies accompanied with the simulations using several beam dynamics codes. Settings of beam optics devices from the ECR to MEBT has been developed and applied to meet important project milestones. Similar work is planned for the beam commissioning of the first 3 cryomodules in the superconducting linac.