UPGRADE OF THE NUCLOTRON EXTRACTED BEAM DIAGNOSTIC SUBSYSTEM.

The subsystem is intended for the Nuclotron extracted beam parameters measurements. Multiwire proportional chambers are used for transversal beam profiles measurements in four points of the beam transfer line. Gas amplification values are tuned by high voltage power supplies adjustments. The extracted beam intensity is measured by means of ionization chamber, variable gain current amplifier DDPCA-300 and voltage-to-frequency converter. The data is processed by industrial PC with National Instruments DAQ modules. The client-server distributed application written in LabView environment allows operators to control hardware and obtain measurement results over TCP/IP network. THE PROBLEM STATEMENT The project to construct a new accelerator complex NICA (Nuclotron-based Ion Collider fAcility) on the basis of the modernized existing Nuclotron accelerating facility is under active development at JINR. The modernization of the Nuclotron set the task to develop and put into operation a modern data acquisition and control systems. It is important to keep the existing functionality during accelerator runs while improving the graphic user interface, hardware control convenience, operation speed and stability. Fundamental principles of the control system organization are as follows:  the client-server distributed model of data exchange,  equipment operation reliability,  applications operation stability in the long accelerator run. The wide range of the acquisition electronics and software produced by National Instruments is quite satisfactory to solve the above tasks. A wide range of functions available in NI multifunction data acquisition modules allows to use only a few hardware modules to realize all necessary tasks. The software is based on .NET Framework, NI-DAQmx universal driver set and powerful graphics.