Fast scintillator strip position detector with R7400 photomultiplier readout used in ZEUS experiment at HERA II

A position-sensitive scintillator strip detector used for the Luminosity Monitor of the ZEUS experiment is described. The detector readout based on Hamamatsu R7400 photomultipliers is presented. The detector offers a satisfactory spatial resolution of 3 mm and a good signal to noise ratio that allows to run at a rate of up to 10 MHz. The data obtained with the position detector are used for the luminosity measurement in ZEUS and also for the monitoring and on-line correction of the HERA II beams.