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For decades, synchrotron radiation facilities have provided powerful research tools for a variety of photon sciences, industrial use, and other purposes. In [[9]], we discussed the suppression of emittance variation in extremely low emittance light sources and demonstrated that the emittance variation could be reduced to less than 1% and passively maintained by carefully optimizing the operating condition of insertion devices. The electron energy was optimized at 6 GeV to reduce the natural electron emittance, while covering the same range of X-rays with shorter period undulators. There is no such magnet for NanoTerasu and, more importantly, the LGB magnets are expected to be made using a permanent magnet for SPring-8-II that does not exist for NanoTerasu. [Extracted from the article]

The CeB6(001) single crystal used as a cathode in a low‐emittance electron gun and operated at the free‐electron laser facility SACLA was investigated using cathode lens electron microscopy combined with X‐ray spectroscopy at SPring‐8 synchrotron radiation facility. Multilateral analysis using thermionic emission electron microscopy, low‐energy electron microscopy, ultraviolet and X‐ray photoemission electron microscopy and hard X‐ray photoemission spectroscopy revealed that the thermionic electrons are emitted strongly and evenly from the CeB6 surface after pre‐activation treatment (annealing at 1500°C for >1 h) and that the thermionic emission intensity as well as elemental composition vary between the central area and the edge of the old CeB6 surface. [ABSTRACT FROM AUTHOR]

For many years, scientists around the world have sought an ultra-low-emittance ring-based light source that offers greater performance than existing third-generation light sources. Pioneering work on the seven-bend lattice for MAX IV [1] initiated these efforts. Another significant development was the scheme for nonlinearity control based on “phase-matched” sextupole pairs. This configuration, first introduced in a light source design by the ESRF design group [2], efficiently suppresses strong nonlinear resonances induced by sextupoles for chromaticity correction. Since a small dynamic aperture due to the strong nonlinearities mentioned earlier presents a great obstacle when we attempt to lower the beam emittance of a high-energy light source using individual bending magnets with small deflection angles, the ESRF scheme contributes significantly to the emittance reduction that can be practically achieved. [ABSTRACT FROM PUBLISHER]