On June 23, the Frank Laboratory of Neutron Physics held a Memorial Seminar devoted to the 60th anniversary of the start-up of the IBR reactor. The Seminar was held both in the FLNP Conference Hall and in a video-conference format.

The Seminar was opened with a short historical review delivered by FLNP Director V.N. Shvetsov. He also conveyed greetings from the Bulgarian colleagues, cooperation with whom has been continuing for many years. Professor P. Petrov, Director of the Institute of Electronics, BAS, congratulated the FLNP employees on the glorious date and wished them new remarkable scientific achievements.

On June 23, 1960, exactly 60 years ago, the first FLNP pulsed reactor reached pulsed criticality, about which a corresponding historical note was made in the Laboratory’s logbook and evidenced by the signatures of all participants in the power start-up. The IBR started a dynasty of pulsed reactors at JINR, later continued by IBR-30 and IBR-2. Next, Yu.N. Pepelyshev presented the concept of a pulsed reactor, further developing the ideas embodied in the IBR-2 (co-authors A.V. Vinogradov, A.D. Rogov, S.F. Sidorkin). The authors assume that it will be possible to minimize the amount of design and development work and use previous successful developments and solutions. The main difference from the IBR-2 reactor is that the units of the reactor control and safety system will be moved inside the core, as is done in the BOR-60, MBIR and BN-600 reactors. This will make it possible to place neutron moderators maximally close to the reactor vessel and improve the level of protection. Also, among the advantages of the project is the possibility of using the reactivity module developed for the modernized IBR-2 reactor and part of its spectrometers.

The report raised many questions, which resulted in discussions in the Conference Hall and on the Internet. V.N. Shvetsov, thanking the speaker, noted that this speech does not mean that the FLNP has not chosen a project for a new neutron source.