Shatilov, D.N. JACoW Publishing Geneva, Switzerland 978-3-95450-216-5 10.18429/JACoW-eeFACT2018-TUYBA02 English 106-111 TUYBA02 luminosity resonance betatron ECR collider Contribution to a conference proceedings 2019 2019-04 https://doi.org/10.18429/JACoW-eeFACT2018-TUYBA02 http://jacow.org/eefact2018/papers/tuyba02.pdf One of the main requirements for future e⁺e⁻ colliders is high luminosity. If the energy per beam does not exceed 200 GeV, the optimal choice will be a circular collider with "crab waist" collision scheme. Here, to achieve maximum luminosity, the beams should have a very high density at the IP. For this reason, radiation in the field of a counter bunch (BS - beamstrahlung) becomes an appreciable factor affecting the dynamics of particles. In particular, in the simulation for FCC-ee, new phenomena were discovered: 3D flip-flop and coherent X-Z instability. The first is directly related to BS. The second can manifest itself at low energy (where BS is negligible), but at high energies BS substantially changes the picture. In the example of FCC-ee, we will consider the features of beam-beam interaction at high-energy crab waist colliders, and optimization of parameters for high luminosity.