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TY - CONF AU - Shimosaki, Y. AU - Soutome, K. AU - Takao, M. AU - Tanaka, H. ED - Koscielniak, Shane ED - Satogata, Todd ED - Schaa, Volker RW ED - Thomson, Jana TI - Simulation Studies of Beam Commissioning and Expected Performance of the SPring-8-II Storage Ring J2 - Proc. of IPAC2018, Vancouver, BC, Canada, April 29-May 4, 2018 C1 - Vancouver, BC, Canada T2 - International Particle Accelerator Conference T3 - 9 LA - english AB - In the SPring-8 upgrade project, the 5-bend achromat lattice is adopted for achieving a very low emittance of 157 pm.rad at 6 GeV. Since the dynamic aperture (DA) and the beam performance become sensitive against errors due to the strong quadrupoles and sextupoles, we carried out tracking simulations to evaluate the tolerance of machine imperfections such as the misalignment, magnetic field errors, the BPM offset, etc. It is found that the first-turn-steering (FTS) with the use of single-pass BPM's is indispensable because even under strict (but attainable) tolerances the beam cannot be stored without steering kicks. We then confirmed that after the FTS a sufficiently large DA can be obtained for accumulating the beam by the off-axis injection. By performing the orbit and optics corrections for the stored beam, we can finally achieve an emittance value of 160 ~ 180 pm.rad, being close to the design value. We also found that a naive application of the SVD algorithm to orbit corrections yields unwanted local bumps between BPM's and this deteriorates the vertical emittance. A possible scheme to avoid such local bumps by effectively interpolating the measured orbit will be discussed. PB - JACoW Publishing CP - Geneva, Switzerland SP - 4203 EP - 4205 KW - emittance KW - quadrupole KW - lattice KW - simulation KW - sextupole DA - 2018/06 PY - 2018 SN - 978-3-95450-184-7 DO - 10.18429/JACoW-IPAC2018-THPMF059 UR - http://jacow.org/ipac2018/papers/thpmf059.pdf ER -