Experimental set-up for multiplication coefficient fluctuation study vs. accelerator parameter deviations on the JINR pulsed accelerator driven neutron source

The conception of an electron beam-driven subcritical molten salt safety reactor (MSR) was presented at the International Conference on Accelerator-Driven Transmutation Technologies and Application (ADTT) [1]. The essence of the concept is the use of the MSR cascade system to reduce the driving power. The cascade reactor could allow diminishing of the beam power down to a value where the electron accelerator could be used. The question is how much the neutron multiplication coefficient may be used in the ultimate safety reactor design. The Joint Institute for Nuclear Research (Dubna) has a facility, which could be named as a prototype of the future accelerator driven subcritical reactor. It is the 1BR-30 pulse reactor driven by the S-band electron linac (LUE-40). Here the neutron multiplication coefficient of ≈200 (the same as the value of subcriticality k_eff=0.995) from the coupled facilities allows an integral yield of 0.5×10¹⁵ neutrons per second at a pulse width of 4 microseconds. These facilities form the JINR experimental set-up for the study on multiplication coefficient fluctuations vs. deviation of accelerator driven parameters, as well as for the steady state and transient regimes. The experimental set-up for these studies and the first results will be presented