First data at Belle II and Dark Sector physics

Sumitted to PubDB: 2018-07-23

Category: Proceeding, Visibility: Public

Tags: -

Authors	Giacomo De Pietro
Date	July 21, 2018
Belle II Number	BELLE2-CONF-PROC-2018-012
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.