Status of SuperKEKB Project: Accelerator Design and Construction Progress

by Yukiyoshi Ohnishi (KEK)

Tuesday 7 Jul 2015, 11:00 → 12:30 Europe/Rome

Aula Divisione Acceleratori (LNF INFN)

The SuperKEKB project is a positron-electron collider built to explore new phenomena in particle physics. The physics program of the next B- factory delivering ultra high statistics is almost independent of, and/or complementary to, the high energy experiments at the LHC. The target luminosity is 8x10^35 cm^-2s^-1, which is 40 times the performance of the previous KEKB accelerator, which has been operated during 11 years until 2010. The consideration of SuperKEKB began in 2001. The strategy for the luminosity upgrade was a high-current scheme in the early stage. However,difficulties such as a bunch lengthening due to coherent synchrotron radiation and the need for a huge reinforcement of the RF system were encountered. As a result, in 2009 we have changed the strategy from the previous high-current to a novel "nano-beam" scheme. The nano-beam scheme was first proposed by P. Raimondi in Italy. Here the collision of low emittance beams under a large crossing angle allows squeezing the beta function at IP to values much smaller than the bunch length. Consequently, the 40 times higher target luminosity can be achieved with only twice the beam current of KEKB. The commissioning of SuperKEKB will start in early next year. In this seminar the latest upgrade schedule and the recent progress of the accelerator construction will be presented.

Slides Status_of_SuperKEKB_Frascati.pdf