In physics,our expectations for system behavior are often guided by intuitive arithmetic.For systems composed of identical units,we anticipate synergy of the contributions from these units,where 1+1=2.Conversely,for s...In physics,our expectations for system behavior are often guided by intuitive arithmetic.For systems composed of identical units,we anticipate synergy of the contributions from these units,where 1+1=2.Conversely,for systems built from opposing units,we expect cancellation of their contributions,where 1-1=0.This intuitive arithmetic has long underpinned our understanding of physical properties of materials,from electronic transport to optical responses.However,scientific breakthroughs often occur when nature reveals ways to circumvent these seemingly fundamental rules,opening new possibilities that challenge our deepest assumptions about material behavior.展开更多
166.6-MHz quarter-waveβ=1 superconducting cavities have been adopted for the High Energy Photon Source,a 6-GeV diffraction-limited synchrotron light source currently under construction.A large helium jacket was requi...166.6-MHz quarter-waveβ=1 superconducting cavities have been adopted for the High Energy Photon Source,a 6-GeV diffraction-limited synchrotron light source currently under construction.A large helium jacket was required to accommodate the enlarged cavity beam pipe for the heavy damping of higher-order modes;the original electric-probe pickup thus becomes inevitably long with unfavorable mechanical properties.Relocated to an existing high-pressure-rinsing port,a magnetic-loop pickup was designed,characterized by low radio-frequency and cryogenic losses and being multipacting-free and insensitive to manufacturing and assembly tolerances.The consequent removal of the original pickup port from the cavity largely simplified the helium jacket fabrication and may also reduce cavity contamination.This paper presents a comprehensive design of a low-loss magnetic-coupling pickup for quarter-waveβ=1 superconducting cavities.The design can also be applied to other non-elliptical structures.展开更多
基金supported by the National Natural Science Foundation of China (Grant No.12374109)the National Key Research and Development Program of China (Grant No.2023YFA1406600)。
文摘In physics,our expectations for system behavior are often guided by intuitive arithmetic.For systems composed of identical units,we anticipate synergy of the contributions from these units,where 1+1=2.Conversely,for systems built from opposing units,we expect cancellation of their contributions,where 1-1=0.This intuitive arithmetic has long underpinned our understanding of physical properties of materials,from electronic transport to optical responses.However,scientific breakthroughs often occur when nature reveals ways to circumvent these seemingly fundamental rules,opening new possibilities that challenge our deepest assumptions about material behavior.
基金supported by High Energy Photon Source(HEPS)projecta major national science and technology infrastructure。
文摘166.6-MHz quarter-waveβ=1 superconducting cavities have been adopted for the High Energy Photon Source,a 6-GeV diffraction-limited synchrotron light source currently under construction.A large helium jacket was required to accommodate the enlarged cavity beam pipe for the heavy damping of higher-order modes;the original electric-probe pickup thus becomes inevitably long with unfavorable mechanical properties.Relocated to an existing high-pressure-rinsing port,a magnetic-loop pickup was designed,characterized by low radio-frequency and cryogenic losses and being multipacting-free and insensitive to manufacturing and assembly tolerances.The consequent removal of the original pickup port from the cavity largely simplified the helium jacket fabrication and may also reduce cavity contamination.This paper presents a comprehensive design of a low-loss magnetic-coupling pickup for quarter-waveβ=1 superconducting cavities.The design can also be applied to other non-elliptical structures.
