PoS(ICHEP2016)703 A scintillation counter consisting of a pure CsI crystal, WLS and APD for Belle II H. Aihara The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan D. A. Epifanov Budker Institute of Nuclear Physics, akademika Lavrentieva prospect, Novosibirsk, 630090, Russian Federation Y. Jin * The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan E-mail: jin@hep.phys.s.u-tokyo.ac.jp K. Wan The University of Tokyo, 7-3-1 Hongo Bunkyo-ku, Tokyo 113-0033, Japan Belle II, as the upgrade of Belle, aims to search for New Physics with 40 times higher lumi- nosity. In order to cope with such a high luminosity, an electromagnetic calorimeter using pure CsI scintillation crystals, whose scintillation time are around 30 nanoseconds, has been proposed. Silicon avalanche photodiodes (APD), making up for the low light yield of pure CsI, are consid- ered as photosensors. The application of the innovative wavelength shifter (WLS) that perfectly matches the emission spectrum of pure CsI and the quantum efficiency of APD maximizes the light collection. The equivalent noise energy of the counter is determined using cosmic rays. 38th International Conference on High Energy Physics 3-10 August 2016 Chicago, USA * Speaker. c  Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/