History of Science and Engineering Annotation << Back THE FIRST OUR COUNTRY`S HARD FOCUSING LINEAR PROTON ACCELERATOR I-2 – 5 0 YEARS IN ACTION A.M. Kozodaev, N.V. Lazarev, V.S. Stolbunov It is told about the 50-year path of the first in the country linear proton accelerator with a hard focus of I-2 for 25 MeV energy from the origin of the idea of its creation until today. Information is provided on the numerous upgrades of the accelerator, the modes of its operation, the use of a proton synchrotron as an injector, and an independent installation for applied work. It is informed about the received experience and the carried out researches and workings out which can be actual now. Keywords: rigid-focusing accelerator; proton; injector; Linear accelerator. Contacts: E-mail: A.Kozodaev@itep.ru Pp. 31-44.