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171:. The ring for electrons, having energy of 8 GeV, is called the high-energy ring (HER), while the ring for positrons, having energy of 3.5 GeV, is called low-energy ring (LER). The HER and LER are constructed side by side in the tunnel, which has been excavated already in the past for the former TRISTAN accelerator. TRISTAN was the first site to confirm
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on each of its accelerating beams to rotate the bunches of accelerating electrons or positrons, hoping to further increase its luminosity. However, the improvement is not clear and currently under tuning.
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experiment, which is an upgrade of the Belle experiment (located at the same site as Belle). The Belle experiments studied b-quark hadrons to research CP violation.
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around an electron and operated at center-of-mass energies between 50 and 61.4 GeV. There were three experiments at the old TRISTAN accelerator: Venus, Topaz, and
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of each ring is 3016 m, having four straight sections. In the KEKB, there is only one interaction point in the "Tsukuba area", where the
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A section of the KEKB accelerator. The left-hand ring (blue) is for electrons, and the right-hand ring (green) is for positrons.
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upgrade of KEKB. SuperKEKB had its first particle collisions in 2018. The SuperKEKB accelerator produces particle beams for the
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K. Akai et al., "RF systems for the KEK B-Factory", Nuclear
Instruments and Methods in Physics Research A 499 (2003) 45–65
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KEKB's leading finite crossing angle interaction design provides its high luminosity. In the last upgrade, KEKB installed
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Levine, I.; TOPAZ Collaboration (1997). "Measurement of the
Electromagnetic Coupling at Large Momentum Transfer".
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is located. The other areas (called "Fuji", "Nikko" and "Oho") are currently not actively used by an experiment.
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technology, whereas the RF cavities in the LER use a normal conducting design denoted ARES. The
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Particle accelerator at the High Energy
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due to its property of decaying into other lighter mesons. KEKB was basically an
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23:A schematic of the KEKB accelerator complex.
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179:. The RF cavities in the HER use
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330:Particle physics facilities
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283:10.1103/PhysRevLett.78.424
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141:having the energy of 8
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