Optical Emission Spectroscopy diagnostic on MITICA - System Description

In PRIMA test bed both SPIDER and MITICA experiments will be equipped with Optical Emission Spectroscopy diagnostics whose aim is to measure the homogeneity, the divergence and the stripping losses of the beam after the acceleration grids (Beam Emission Spectroscopy), and to monitor the plasma inside the source (Source Emission Spectroscopy). MITICA and SPIDER OES diagnostics must share as much as possible their hardware components for cost savings. SPIDER OES design has been already finalised in reports RFX_SPIDER_TN_116 and RFX_SPIDER_TN_124, while the report RFX_MITICA_TN_106 proved that SPIDER BES can fit also for MITICA, with a proper choice of the diagnostic setup. This document reports on system requirements of BES on MITICA, system design with functional specifications based on the signal estimate derived from physics principles of the measurements and from the constraints of the experimental layout and available technology, system layout, interfaces with the vacuum vessel and the PRIMA buildings. It also discusses the system requirements, preliminary design and layout of SES in MITICA, according to the present status of MITICA source design.