Speaker
Description
Unlike the situation under the third-generation light sources, we will have to pay more attention to control electron beam loss under the fourth-generation ones. The main causes of the beam loss are (i) a beam dumped by switching off RF cavities and (ii) electrons lost by electron-electron scattering (the Touschek effect). Due to the low emittance, if the highly-dense dumped beam directly hits a chamber, that will induce a vacuum accident. Due to the short beam lifetime, the number of scattered electrons hitting insertion devices (IDs) increases, and demagnetization would severely shorten the ID lifetime to be less than 10 years. Here we evaluate and elucidate how a dumped beam and scattered electrons are lost in the storage ring. To investigate the process of Touschek loss, we developed an analytical method following Piwinski’s formulation and calculated the spatial and energy distributions along the ring. Taking SPring-8-II as an example, our calculation indicates that a beam shaker is effective to reduce beam power density, and the installation of vertical scrapers in the long straight sections and shielding materials in the IDs can prevent the component damage of the ring.
Region represented | Asia |
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