Giacomo De Pietro

21 July 2018

Abstract: Belle II is a major upgrade of the Belle experiment that operates at the $B$-factory SuperKEKB in Japan. Since SuperKEKB has a design luminosity of 8$\;\times\;$10$^{35}$ cm$^{-2}$s$^{-1}$, about 40 times larger that of KEKB, Belle II aims to collect $50$ ab$^{-1}$ of data over a period of 8 years. The first data taking runs for physics analyses have started in April 2018, with a lower luminosity than the designed one for commissioning purposes. Even with the early dataset (having an integrated luminosity up to 20 fb$^{-1}$), Belle II can improve the searches for Dark Sector candidates. In this paper we will present the expected sensitivity of Belle II for invisibly decaying Dark Photons, for Axion-Like Particles and for invisibly decaying $Z^{\prime}$ assuming a $L_{\mu}-L_{\tau}$ model.

Note: Proceeding of "The International Conference on B-Physics at Frontier Machines - BEAUTY2018", held in La Biodola (Elba island, Italy) from May 6th to May 11th, 2018