The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
TY - CONF AU - Soutome, K. AU - Kaneki, K.K. AU - Shimosaki, Y. AU - Takao, M. AU - Tanaka, H. ED - Schaa, Volker RW ED - Petit-Jean-Genaz, Christine ED - Ko, In Soo ED - Kim, Dong Eon ED - Kim, Kyung Sook TI - Non-linear Optimization of Storage Ring Lattice for the SPring-8 Upgrade J2 - Proc. of IPAC2016, Busan, Korea, May 8-13, 2016 C1 - Busan, Korea T2 - International Particle Accelerator Conference T3 - 7 LA - english AB - A project of upgrading the SPring-8 facility is ongoing to convert the present storage ring to a high-coherence hard X-ray source (SPring-8-II). To achieve the emittance value of less than 0.2 nmrad at 6 GeV, we adopted a 5-bend achromat lattice with dipoles having longitudinal field gradient. In this lattice the betatron phase between the two dispersion arcs was set to (2n+1)PI to suppress dominant harmful effects of chromaticity-correcting sextupoles. By detuning this phase, optimizing sextupole strengths in a cell and introducing octupoles, we obtained a sufficient dynamic aperture (DA) for beam injection even for the symmetry-broken ring having four long straight sections and a high-beta injection section. However, the off-momentum behavior such as the non-linear chromaticity still needs to be optimized to achieve the momentum acceptance (MA) of 3% or larger. We have thus been investigating the possibility to increase both the DA and MA by introducing several phase-matched sextupole pairs. The presentation will report the obtained results by this approach. PB - JACoW CP - Geneva, Switzerland SP - 3440 EP - 3442 KW - sextupole KW - lattice KW - betatron KW - optics KW - injection DA - 2016/06 PY - 2016 SN - 978-3-95450-147-2 DO - 10.18429/JACoW-IPAC2016-THPMR022 UR - http://jacow.org/ipac2016/papers/thpmr022.pdf ER -