1 February 1947 – The Bulgarian National Assembly voted a new law, which restored the old name – BAS. The Academy was defined as “the highest scientific institution in the country”, “a state institution with its own creative, organizational and administrative life”, which was under the authority of Council of Ministers.

27-28 February 1947 – adoption of the Statute of BAS

On 4 March 1947, Todor Pavlov was elected President of the Academy.

In September 1949, the structure of BAS was changed. The departments and branches were replaced by 7 divisions for: physics, mathematics and technical sciences; geological-geographic and chemical sciences; biological and medical sciences; history, archaeology and philosophy; legal and economic sciences; linguistics, ethnography and literature; fine arts and culture. The institutes of the Academy were defined as the main research bodies of BAS.

New regulations for the PhD degree at BAS were adopted in 1951.

1957 – Agreements were concluded with the Polish Academy of Sciences, the German Academy of Sciences at Berlin, the German Academy of Agricultural Sciences, the Czechoslovak Academy of Sciences and the Academy of the People’s Republic of Romania.

1960 – a Technical Sciences division was established at BAS with the following institutes: Institute of Energetics, Technical Institute, Institute of Urban Planning and Architecture. The division of Technical Sciences also had separate sections on automation and telemechanics and on metal science and metal technology.

In the picture: Academician Todor Pavlov

On 28 August 1961, the Council of Ministers issued a decree on the establishment of an independent Academy of Agricultural Sciences under the Ministry of Agriculture.

In 1961, the first nuclear reactor in Bulgaria was put into operation under the guidance of the then Director of JINR in Dubna, Prof. Dmitry Blokhintsev.

A separate chemical sciences division, including an Institute of General and Inorganic Chemistry, Institute of Organic Chemistry and Institute of Physical Chemistry was established in 1961.

In 1961, the method of gas counter pressure casting was approved, created by Acad. Angel Balevski and corr.-mem. Ivan Dimov which was designed for obtaining materials with optimal structure, without defects in the metal. Counter pressure casting has been widely used in the automotive industry, especially in the production of wheel rims, and has been used with outstanding success by leading automotive companies in 25 countries.

In 1962, the first Bulgarian digital electronic tube computerized machine with the program “Vitosha” was created and installed.

At the end of 1962, the Institute of Physics of BAS was renamed the Institute of Physics with Atomic Scientific Experimental Base at BAS.

In the picture: The Reactor in the building of the Institute of Nuclear Research and Nuclear Energy

1964 – a new institute in the field of historical sciences – Institute of Balkan Studies – was set up to study the past of the Balkan peoples and to promote their cooperation.

In 1964, the first Bulgarian and the fourth in the world electronic calculator “Elka” was implemented in production.

In September 1967, a Central Laboratory of Photographic Processes was established at the Institute of Physical Chemistry, aiming at exploring new phenomena in photography. A Research Center for Africa and Asia was also set up to explore the economic and political processes in developing countries in this region. In order to strengthen the research of the social processes in society and to clarify the regularities of its development, an Institute of Sociology is established at the Academy.

In 1969, the 100th jubilee from the establishment of BAS was celebrated.

In the period 1969-1970, an experimental model for integration between the Faculty of Mathematics of Sofia University and the Institute of Mathematics and Mechanics of BAS was created.

In the picture: The first Bulgarian electronic calculator “Elka”, weighing 8.5 kilograms, with 3 registers and working with 12 decimal numbers

On 21 April 1972, a Decree of the Council of Ministers was issued, according to which the divisions of BAS were replaced by Unified Centers for Science and Training of Staff (UCSTS). Thus, functional integration with Sofia University was sought.

21 December 1972 – The General Assembly of BAS adopted a new Statute of the Academy. A new reorganization of the institution was made on the basis of it. The Statute was approved by State Council Decree No 1029 of 4 May 1973.

In 1972, the Institute of Thracology at BAS was founded, with print editions: Orpheus, Journal of Indo-European and Thracian Studies and Studia Thracica.

1977 – the technical units (Institute of Technical Cybernetics, Institute of Metal Science and Metal Technology, Institute of Water Problems, Central Laboratory of Physical and Chemical Mechanics) came out of UCSTS and formed a new Scientific Union on basic problems of the technical sciences.

In 1975, in the automotive industry of the Eastern European countries, the wide implementation of the bright acid copper plating B-7211 began. It was created by a team of scientists at the Institutes of Organic Chemistry and Physical Chemistry of BAS and in the following years it was used in the production of over 1 500 000 cars.

1979 – The Central Laboratory of Applied Physics at BAS which works in the field of theory and application of optoelectronics and semiconductor sensors became a subsidiary of the laboratory of the Nobel laureate Academician Joris Alferov at the Physico-Technical Institute “A. F. Joffe” in Leningrad.

In the picture: The first edition of Studia Thracica

In 1981, the so-called Golden Book of Discoverers and Inventors in Bulgaria was established.

On 14 July 1988, in accordance with the project “Basic Guidelines and Tasks for the Reconstruction of the Scientific Front”, the Politburo of the Bulgarian Communist Party decided to close down the nine existing Unified Centers of BAS, as well as the Scientific Unions and the independent institutes.

On 25 July 1988, the General Assembly of Academicians and Corresponding Members, as the supreme governing body of the Academy, elected Academician Blagovest Sendov President of BAS.

In the picture: Acad. Blagovest Sendov