Kuriki, M. Hayano, H. Jin, X.J. Kashiwagi, S. Konomi, T. Piot, P. Power, J.G. Sakaue, K. Seimiya, Y. Washio, M. Yamamoto, N. Zhao, H.W. JACoW Publishing Geneva, Switzerland 2226-0366 978-3-95450-194-6 10.18429/JACoW-LINAC2018-THPO005 English 685-687 THPO005 emittance gun collider simulation linear-collider Contribution to a conference proceedings 2019 2019-01 https://doi.org/10.18429/JACoW-LINAC2018-THPO005 http://jacow.org/linac2018/papers/thpo005.pdf Linear colliders is the only way to realize e⁺ e⁻ collision at higher energy beyond the limit of ring colliders by the huge synchrotron radiation energy loss. In the linear collider, the beam current should be much smaller comparing to the ring collider to save the required electricity. A way to realize an enough luminosity with the small beam current and less energy spread by Beamstrahlung, is collision in flat beam. This high aspect ratio beam can be made by phase-space rotation technique instead of the conventional way with DR (Damping Ring). We present a simulation of this technique and pilot experiments at KEK-STF and ANL WFA.