On Friday, 26 February 2021, a jubilee seminar of the department “Relativistic nuclear physics and polarization phenomena” will take place in honor of the 95th anniversary of the birth of Academician Alexander Mikhailovich Baldin.

The seminar will be held online on the Webex platform. The event will start at 10:00 AM.

Link to join online seminar

More details about reports

Moreover, the JINR Science and Technology Library invites to the literature exhibition dedicated to the 95th anniversary of the birth of Academician A. M. Baldin. Alexander Mikhailovich Baldin founded a new scientific realm called relativistic nuclear physics. The Nuclotron, a superconducting accelerator of a new type, was created under his leadership. The library will exhibit scientific papers and biographical materials about A. M. Baldin. The exhibition will open on 25 February.

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On 95th anniversary of Academician Alexander Mikhailovich Baldin
(1926-2001)

Academician Alexander Mikhailovich Baldin, an outstanding scientist in the field of elementary particle physics and the atomic nucleus, was born on 26 February 1926 in Moscow in the Krasnaya Presnya district. The youth and student life of Alexander Mikhailovich fell on the harsh, hungry years of the war and post-war reconstruction. He became a student of the Moscow Institute of Transport Engineers. In 1946, among other excellent students, he had been invited to continue his education at the newly established Moscow Mechanical Institute of Ammunition, later the Moscow Engineering and Physics Institute. In 1949, after graduating from the Moscow Engineering Physics Institute, he went to the Lebedev Physical Institute of the USSR Academy of Sciences, where he rose from a junior researcher to the head of the theoretical sector, became a doctor of science and professor.

Back in the early 1950s, in connection with the development of work at the FIAN electronic synchrotron and at the initiative of M. A. Markova, A. M. Baldin (in collaboration with V. V. Mikhailov) carried out pioneering calculations of the cross-sections for the production of mesons on nucleons and nuclei which were irradiated with high-energy photons. Works in this direction were awarded the USSR State Prize for 1973.

In 1968, Alexander Mikhailovich, on the initiative and with the support of academician M. A. Markova was elected director of the Laboratory of High Energies of the Joint Institute for Nuclear Research (Dubna). The young man was responsible for the formulation of the actual scientific programme of the team, founded by V. I. Veksler, and preserving and increasing the research base, first of all, the “Veksler heritage” – the synchrophasotron.

The interactions of nuclei at relativistic energies were chosen as the first priority study. For this purpose, under the leadership of Alexander Mikhailovich, the synchrophasotron was transformed into an original accelerator complex of relativistic and polarized nuclei.

In the early 70s, Alexander Mikhailovich defined long-term research goals in relativistic nuclear physics as a priority area for domestic science based on the intersection of atomic nucleus and elementary particle physics. This direction immediately turned out to be aimed to establish the limits of applicability of the proton-neutron model of the atomic nucleus and to develop a physical picture of nuclear matter at the level of the subnucleon components – quarks and gluons.

Following Dubna, relativistic nuclear physics became an essential part of the programs of the largest accelerator centres in the USA, Europe, Russia, and the JINR member states. At the same time, the Laboratory dynamically developed an extensive experimental program of cooperation in high energy physics with the Institute of High Energy Physics (Protvino), FNAL (USA) and the European Organization for Nuclear Research (Switzerland).

The first success in this direction was Baldin’s prediction of the nuclear cumulative effect. As shown by the first experiments in Dubna (at energies of several GeV) the production of particles in nuclear collisions enters the asymptotic regime. In the parton model language, this circumstance indicated the presence of multiquark (multinucleon) states in nuclei.

The discovered empirical regularities allowed A. M. Baldin to introduce a universal momentum distribution of partons in nuclei – the quark-parton structure function of the nucleus which sharply intensified interest in the development of a theory for describing the nucleus at distances less than the nucleon size (models of fluctons, short-range nucleon correlations, multiquark states in nuclei, etc.).

A. M. Baldin proposed universal approaches to describing not only the spectra of single particles but also to describe the whole picture of the multiparticle production in nuclear collisions. He proposed a description of the process of nuclear interactions in 4-dimensional velocity space based on the principles of symmetry – self-similarity symmetry. The picture of multiparticle production has found an analogy in the macroscopic process of a “point explosion”. This universal law was discovered and studied and it makes it possible to describe the cumulative, subthreshold processes, the processes of antinuclear formation, as well as processes in the transition region from nucleon to quark-gluon variables.

The results of this new direction (relativistic nuclear physics), together with the fundamental works of the N. N. Bogoliubov theoretician school compiled a unified set of works to identify the dynamic role of the new quantum number “colour” and the corresponding symmetry in the implementation to observed the scale-invariant behaviour of hadronic and nuclear interactions with large momentum transfer. They were awarded the 1988 Lenin Prize.

Under the leadership of Alexander Mikhailovich the new accelerator base of the Laboratory of High Energies was developed. The new ion sources and experimental zones of accelerated beams were created. The unique beams of polarized deuterons and neutrons were created. Experiments with beams of polarized deuterons were formed in a special direction of research. They obtained unique information about the spin structure of the deuteron (this “hydrogen atom of nuclear physics) at internucleon distances less than the nucleon radius.

With the launch and development of the Nuclotron in the 90s qualitatively new opportunities arose for studying the properties of atomic nuclei. Domestic physics, the science of the JINR member countries received a powerful basis for first-class research in the physics of strong interactions.

The scientific and organizational activities of Alexander Mikhailovich were extremely multifaceted. He was the chairman of the Council for Electromagnetic Interactions of the Russian Academy of Sciences, the member of the Bureau of the Department of Nuclear Physics of the Russian Academy of Sciences, editor-in-chief of the journals “Physics of elementary particles and the atomic nucleus” (PEPAN) and “Letters to PEPAN”, a member of the editorial boards of many scientific publications.

Achievements of the outstanding scientist and major organizer of science academician A. M. Baldin were awarded the State Prize, the V. I. Veksler Prize of the Russian Academy of Sciences, orders and medals of Russia, Bulgaria, Vietnam, Mongolia, Poland, Czech Republic, awards of other countries. Alexander Mikhailovich was awarded the title of honorary citizen of Dubna.