Alexander Smirnov

Achievement of Necessary Vacuum Conditions in the NICA Accelerator Complex

NICA is the accelerator collider complex under construction at the Joint Institute for Nuclear Research in Dubna. The facility is aimed at providing collider experiments with heavy ions up to Gold in a center of mass energy range from 4 to 11 GeV/u and an average luminosity up to 10 27 cm -2 s -1 . The collisions of polarized deuterons are also foreseen. The facility includes two injector chains, a new superconducting booster synchrotron, the existing superconducting synchrotron Nuclotron, and a new superconducting collider consisting of two rings, each of about 500 m in circumference [1]. Vacuum volumes of the accelerator booster and Nuclotron and the superconducting collider are divided into volumes of superconducting elements thermal enclosure and beam chambers. The beam chambers consist regular cold periods, which are at a temperature of 4.2K to 80K, and warm irregular gaps at room temperature. Operating pressure in thermal enclosure vacuum volumes have to maintained in the range of 1×10 to 1×10 mbar, in the beam chamber cold and warm areas – not more than 2×10 mbar. The description of way to achievement and maintenance of the working vacuum in the NICA project

Commissioning of New Light Ion RFQ Linac and First Nuclotron Run with New Injector

In the frames of the NICA project development [1] the old HV fore-injector of the LU-20 linac, which was in operation from 1974, was replaced by the new RFQ accelerator in spring 2016. The first Nuclotron technological run with the new LU-20 fore-injector was performed in June 2016. During the following two runs of total duration of about 2500 hours the proton and deuteron (polarized and unpolarized), lithium and carbon beams were successfully injected and accelerated in the Nuclotron ring. Main results of the RFQ commissioning and experience of its operation are presented in this paper.