Manual Calibration System for Daya Bay Reactor Neutrino Experiment

Abstract

The Daya Bay Reactor Neutrino Experiment has measured the last unknown neutrino mixing angle, {\theta}13, to be non-zero at the 7.7{\sigma} level. This is the most precise measurement to {\theta}13 to date. To further enhance the understanding of the response of the antineutrino detectors (ADs), a detailed calibration of an AD with the Manual Calibration System (MCS) was undertaken during the summer 2012 shutdown. The MCS is capable of placing a radioactive source with a positional accuracy of 25 mm in R direction, 20 mm in Z axis and 0.5{\deg} in {\Phi} direction. A detailed description of the MCS is presented followed by a summary of its performance in the AD calibration run.