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In 1965, the electron linear accelerator (Linac) with the beam energy of up to 2 GeV was put into operation at the Kharkov Institute of Physics and Technology (KIPT), thus becoming the largest electron accelerator in Europe at the time. Among the initiators of construction of the facility was Anton K. Valter (1905 – 1965), whereas Pavel V. Sorokin (1930 – 2017) headed the research program on nuclear and particle physics with this accelerator. Over the quarter-century of the accelerator operation, fundamental experimental studies were carried out that have got their due place in the worldwide research activities on electromagnetic processes with nucleons and nuclei. Advanced methods for studying nuclear reactions with photon and electron beams were developed. Particular attention was paid to polarization measurements: the polarized photon beam was obtained and used in numerous experiments, targets of polarized hydrogen and deuterium nuclei were created using superconducting magnets, and particle detection systems were developed (enabling, in particular, proton polarization measurements). The results obtained by Kharkiv physicists on the single pion photoproduction on the proton have been included in the Particle Data Group (PDG) compilations. With the closure of the 2 GeV Linac, the priority in the experimental nuclear and particle physics research carried out at the institute shifted towards extension of the international collaboration. In the early 1990s, in particular, the KIPT group had developed the project of the Møller polarimeter, which was then constructed at the Hall A of the Jefferson Lab (USA) to measure the electron beam polarization. While working on this project, the effect of a substantial impact of the target atomic electron motion on the beam polarization measured with the Møller polarimetry was discovered. Furthermore, the R&D studies were carried out within preparation for the CMS experiment at the LHC – the institute participated in the development of the CMS endcap hadron calorimeter (HCAL), and, later on, it took part in the mass production of the HCAL scintillator tiles. In the early 2000s, preparations started at the NSC KIPT for participation in processing of CMS data. Based on computer simulations, the possibility was estimated to observe a massive Higgs boson in the CMS experiment. Also, a computing facility was constructed, which became the first Ukrainian WLCG site and then (in 2009) was commissioned (under the name of T2_UA_KIPT) as the Tier-2 (T2) center of the CMS grid infrastructure. At present, this facility is the only Ukrainian site that gets the LHC data and provides its processing in the 24/7 regime. After the LHC startup, more than 25 PB of CMS experimental information have been transferred to the T2_UA_KIPT center for processing, and a high level of the site stability and reliability has been provided. In addition to the experiment’s computing infrastructure, the NSC KIPT is also involved in work on the support and upgrades of the CMS hadron calorimetry. Furthermore, the institute takes part in the physics analysis of the data obtained in the experiment. Last years, this work has been mainly focused on searching for supersymmetry signals based on the analysis of proton-proton collision samples recorded in the LHC Run 2 through selection of the events with a large missing transverse momentum and two high transverse-momentum leptons.