JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Beznosov, O. AU - Barber, D.P. AU - Crittenden, J.A. AU - Ellison, J.A. AU - Heinemann, K.A. AU - Hoffstaetter, G.H. AU - Sagan, D. ED - Zimmermann, Frank ED - Tanaka, Hitoshi ED - Sudmuang, Porntip ED - Klysubun, Prapong ED - Sunwong, Prapaiwan ED - Chanwattana, Thakonwat ED - Petit-Jean-Genaz, Christine ED - Schaa, Volker R.W. TI - Spin Matching and Monte-Carlo Simulation of Radiative Spin Depolarization in e⁺e⁻ Storage Rings with Bmad J2 - Proc. of IPAC2022, Bangkok, Thailand, 12-17 June 2022 CY - Bangkok, Thailand T2 - International Particle Accelerator Conference T3 - 13 LA - english AB - The Bmad/Tao software toolkit has been extended to estimate the rate of radiative spin depolarization in e⁺/e⁻ storage rings. First estimates are made using the SLIM algorithm of linearized spin-orbit motion. The extension implements the effects on s-o motion of stochastic photon emission using a Monte-Carlo tracking algorithm. Spins are tracked in 3-D along particle trajectories with the aid of Taylor expansions of quaternions provided by PTC*. The efficiency of long-term tracking is guarantied by the use of a sectioning technique that was exploited in previous-generation software**. Sectioning is the construction of the deterministic s-o maps for sections between the dipoles during the initialization phase. Maps can be reused during the tracking. In a simulation for a realistic storage ring, the computational cost of initial map construction is amortized by the multi-turn tracking computational cost. The use of 1st-order terms in the quaternion expansions to construct the s-o coupling matrices in the matrices of the SLIM algorithm. These matrices are then available for an extension of the optimization facilities in Bmad to minimize depolarizing effects by spin matching. PB - JACoW Publishing CP - Geneva, Switzerland SP - 2383 EP - 2386 KW - polarization KW - resonance KW - storage-ring KW - electron KW - lattice DA - 2022/07 PY - 2022 SN - 2673-5490 SN - 978-3-95450-227-1 DO - doi:10.18429/JACoW-IPAC2022-WEPOMS056 UR - https://jacow.org/ipac2022/papers/wepoms056.pdf ER -