On September 18-22, 2023, the XIV International Symposium “Radiation from Relativistic Electrons in Periodic Structures” and VIII International Conference “Electron, Positron, Neutron and X-ray Scattering under External Influences” will take place. in the city of Tsaghkadzor, Republic of Armenia, the symposium-conference is organized by the Institute of Applied Problems of Physics of the National Academy of Sciences of the Republic of Armenia and Yerevan State University.