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Васильев, Александр Николаевич

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Институт нанотехнологий в электронике, спинтронике и фотонике
Институт ИНТЭЛ занимается научной деятельностью и подготовкой специалистов в области исследования физических принципов, проектирования и разработки технологий создания компонентной базы электроники гражданского и специального назначения, а также построения современных приборов на её основе. ​Наша основная цель – это создание и развитие научно-образовательного центра мирового уровня в области наноструктурных материалов и устройств электроники, спинтроники, фотоники, а также создание эффективной инновационной среды в области СВЧ-электронной и радиационно-стойкой компонентной базы, источников ТГц излучения, ионно-кластерных технологий материалов.​
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  • Публикация
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    Вывод пучка протонов варьируемой интенсивности из ускорителя У-70 с помощью изогнутых кристаллов
    (2025) Решетников, С. Ф.; Афонин, А. Г.; Барнов, Е. В.; Васильев, А. Н.; Маишеев, В. А.; Мочалов, В. В.; Семенов, П. А.; Чесноков, Ю. А; Мочалов, Василий Вадимович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    Представлены результаты работ по управлению интенсивности пучка протонов, выводимого из ускорителя У-70 с помощью изогнутых монокристаллов кремния. Продемонстрирована устойчивая работа вывода пучка, с помощью кристаллов, для двух экспериментов, где требовалась плавная регулировка интенсивности пучка в большом динамическом диапазоне.
  • Публикация
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    Магниты эксперимента СПАСЧАРМ на ускорительном комплексе У-70
    (2023) Мещанин, А. П.; Васильев, А. Н.; Гончаренко, Ю. М.; Кормилицын, В. А.; Минаев, Н. Г.; Мочалов, В. В.; Рыков, В. Л.; Рябов, А. Д.; Рябова, Т. Д.; Рязанцев, А. В.; Семенов, П. А.; Сёмин, С. А.; Симонова, З. Г.; Рыков, Владимир Львович; Мочалов, Василий Вадимович; Васильев, Александр Николаевич; Семенов, Павел Александрович
    Описана система из четырех магнитов, являющаяся частью экспериментальной установки СПА-СЧАРМ на ускорительном комплексе У-70 для исследования спиновых эффектов в адронных взаимодействиях. Уникальный магнит с полем 2.4 Тл и однородностью поля на уровне 10–4 в рабочем объеме 60 см3 служит для накачки и удержания поляризации в поляризованной протон-ной замороженной мишени. Специальный широкоапертурный магнит является центральной ча-стью спектрометра установки на основе дрейфовых трубок. Для прецизионного наведения пучка на центр мишени были изготовлены и введены в состав установки два небольших корректирующих магнита разработки НИИЭФА им. Д.В. Ефремова.
  • Публикация
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    Proposal of the complete experiment for elastic pp and p(bar)p scattering at SPASCHARM program at U70 accelerator
    (2019) Chetvertkova, V. A.; Kalugin, N. K.; Ladygin, V. P.; Bogdanov, A. A.; Mochalov, V. V.; Nurusheva, M. B.; Okorokov, V. A.; Semenov, P. A.; Vasiliev, A. N.; Zherebtsova, L. S.; Богданов, Алексей Александрович; Мочалов, Василий Вадимович; Нурушева, Марина Борисовна; Окороков, Виталий Алексеевич; Семенов, Павел Александрович; Васильев, Александр Николаевич
    © Published under licence by IOP Publishing Ltd.Newly developing SPASCHARM (SPin Asymmetry in CHARMonia) experiment at U70 accelerator will give the unique possibility to measure spin effects with the use of polarized proton and antiproton beams and polarized target. We suggest to carry out the measurements of the pp and p(bar)p elastic scattering spin observables at 16 GeV/c (direct reconstruction of elastic pp and p(bar)p elastic scattering amplitudes at SPASCHARM experiment). To date the direct reconstruction of amplitudes for pp elastic scattering was performed up to 6 GeV/c only, meanwhile there is no available data for p(bar)p elastics scattering. New measurements at SPASCHARM will significantly extend the energy range of the spin studies and will give unique possibility to compare elastic pp and p(bar5)p scattering.
  • Публикация
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    Analytical reconstruction of pp elastic scattering amplitudes from the complete sets of experiments at the SPASCHARM facility at U70
    (2020) Chetvertkova, V. A.; Kozelov, A. V.; Ladygin, V. P.; Bogdanov, A. A.; Mochalov, V. V.; Nurusheva, M. B.; Okorokov, V. A.; Oreshkov, A. O.; Rykov, V. L.; Semenov, P. A.; Vasiliev, A. N.; Богданов, Алексей Александрович; Мочалов, Василий Вадимович; Нурушева, Марина Борисовна; Окороков, Виталий Алексеевич; Рыков, Владимир Львович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    © Published under licence by IOP Publishing Ltd.The direct reconstruction of the pp elastic scattering amplitudes at the energy of 16 GeV is discussed. At the SPASCHARM experiment, the 19 different spin dependent observables will be measured in pp elastic scattering. The suggested selection of observables allows a complete analytical reconstruction of elastic scattering amplitudes as a solution of the system of bilinear equations. A set of physical observables, which are necessary for model independent reconstruction of all five complex elastic pp scattering amplitudes, is defined.
  • Публикация
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    Definition of the NV-center orientations relative to the diamond crystal plane
    (2020) Kukin, N. S.; Kargin, N. I.; Korchevaya, I. O.; Muradova, A. R.; Semenov, P. A.; Vasiliev, A. N.; Каргин, Николай Иванович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    © Published under licence by IOP Publishing Ltd.We investigate the electron spin resonance of an ensemble of Nitrogen-Vacancy color centers in a bulk diamond crystal obtained by CVD-method. The diamond crystal had 1 ppm concentration of nitrogen. The four possible orientations of the NV-center in the crystal lattice lead to different dependences of a magnitude and an orientation of the external static magnetic field. We used the field of 35 Gauss with the vector in the plane of the crystal. We could rotate it to a certain angle within almost 360 degrees around the normal vector to the plane of the crystal. The goal was to define the unknown orientations of the four axes of the NV-centers relatively to the crystal plane. Experimental results obtained at room temperature with a continuous microwave excitation and presented in this paper are in a good agreement with our simulations.
  • Публикация
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    Measurement of single-spin asymmetry for charged pions in the SPASCHARM experiment at U70 accelerator
    (2020) Abramov, V. V.; Kalugin, N. K.; Moiseev, V. V.; Morozov, D. A.; Mochalov, V. V.; Nurusheva, M. B.; Oreshkov, A. O.; Rykov, V. L.; Semenov, P. A.; Vasiliev, A. N.; Мочалов, Василий Вадимович; Нурушева, Марина Борисовна; Рыков, Владимир Львович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    © Published under licence by IOP Publishing Ltd.The SPASCHARM experiment at U70 aims an exploration of a fundamental problem in modern particle physics, the role of spin in strong interactions. At present, the first physics data have been accumulated at a negative 28 GeV beam, interacting with a frozen polarized proton target. The SPASCHARM wide-Aperture spectrometer can detect both charged and neutral particles in the large solid angle with 2π azimuthal coverage in the fragmentation region of beam-particles. It covers the kinematic region of non-perturbative quantum chromodynamics (QCD), where the theoretical predictions are difficult and unreliable due to the full strength quark confinement at low and medium momentum transfers. In this report, the current status of the experiment is presented. The algorithm for reconstructing charged tracks is discussed along with its results on real data and the comparison with the Monte Carlo (MC) simulations. Based on a real track reconstruction, the statistical errors for the measurements of single-spin asymmetries in inclusive charged pion production are estimated. The data analysis is in progress.
  • Публикация
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    Feasibility studies for the measurement of single-spin asymmetry in inclusive K0sproduction at pion beam at U-70
    (2020) Kalugin, N. K.; Moiseev, V. V.; Morozov, D. A.; Mochalov, V. V.; Nurusheva, M. B.; Rykov, V. L.; Semenov, P. A.; Vasiliev, A. N.; Мочалов, Василий Вадимович; Нурушева, Марина Борисовна; Рыков, Владимир Львович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    © Published under licence by IOP Publishing Ltd.In the Spring 2018, the first physics data was accumulated in the new SPASCHARM experiment at U-70 accelerator of IHEP, Protvino. The first stage of SPASCHARM's physics programs prursues the goal of studying spin effects in the beam fragmentation region at an unpolarized negative 28 GeV beam, interacting with a frozen polarized proton target. In this resport, the feasibility of measuring the single spin asymmetry AN in the reaction: π - + p↑→K 0 S + X is evaluated by Monte-Carlo simulations. We present estimates of the detection efficiency as well as for expected event statistics. It is shown that, in the process of interest above, the attainable statistical errors for AN would be at the scale of a few percents.
  • Публикация
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    Study of excited Ξ baryons with the P¯ ANDA detector
    (2021) Barucca, G.; Davi, F.; Lancioni, G.; Mengucci, P.; Mochalov, V.; Semenov, P.; Vasiliev, A.; Мочалов, Василий Вадимович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    © 2021, The Author(s).The study of baryon excitation spectra provides insight into the inner structure of baryons. So far, most of the world-wide efforts have been directed towards N∗ and Δ spectroscopy. Nevertheless, the study of the double and triple strange baryon spectrum provides independent information to the N∗ and Δ spectra. The future antiproton experiment P¯ANDA will provide direct access to final states containing a Ξ¯ Ξ pair, for which production cross sections up to μb are expected in p¯p reactions. With a luminosity of L= 10 31 cm- 2 s- 1 in the first phase of the experiment, the expected cross sections correspond to a production rate of ∼106events/day. With a nearly 4 π detector acceptance, P¯ANDA will thus be a hyperon factory. In this study, reactions of the type p¯p → Ξ¯ +Ξ∗ - as well as p¯p → Ξ¯ ∗ +Ξ- with various decay modes are investigated. For the exclusive reconstruction of the signal events a full decay tree fit is used, resulting in reconstruction efficiencies between 3 and 5%. This allows high statistics data to be collected within a few weeks of data taking.
  • Публикация
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    The potential of Λ and Ξ- studies with PANDA at FAIR
    (2021) Barucca, G.; Davi, F.; Lancioni, G.; Mengucci, P.; Mochalov, V.; Semenov, P.; Vasiliev, A.; Мочалов, Василий Вадимович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    © 2021, The Author(s).The antiproton experiment PANDA at FAIR is designed to bring hadron physics to a new level in terms of scope, precision and accuracy. In this work, its unique capability for studies of hyperons is outlined. We discuss ground-state hyperons as diagnostic tools to study non-perturbative aspects of the strong interaction, and fundamental symmetries. New simulation studies have been carried out for two benchmark hyperon-antihyperon production channels: p¯ p→ Λ¯ Λ and p¯ p→ Ξ¯ +Ξ-. The results, presented in detail in this paper, show that hyperon-antihyperon pairs from these reactions can be exclusively reconstructed with high efficiency and very low background contamination. In addition, the polarisation and spin correlations have been studied, exploiting the weak, self-analysing decay of hyperons and antihyperons. Two independent approaches to the finite efficiency have been applied and evaluated: one standard multidimensional efficiency correction approach, and one efficiency independent approach. The applicability of the latter was thoroughly evaluated for all channels, beam momenta and observables. The standard method yields good results in all cases, and shows that spin observables can be studied with high precision and accuracy already in the first phase of data taking with PANDA.
  • Публикация
    Только метаданные
    PANDA Phase One
    (2021) Barucca, G.; Davi, F.; Lancioni, G.; Mengucci, P.; Mochalov, V.; Semenov, P.; Vasiliev, A.; Мочалов, Василий Вадимович; Семенов, Павел Александрович; Васильев, Александр Николаевич
    The Facility for Antiproton and Ion Research (FAIR) in Darmstadt, Germany, provides unique possibilities for a new generation of hadron-, nuclear- and atomic physics experiments. The future antiProton ANnihilations at DArmstadt (PANDA or PANDA) experiment at FAIR will offer a broad physics programme, covering different aspects of the strong interaction. Understanding the latter in the non-perturbative regime remains one of the greatest challenges in contemporary physics. The antiproton-nucleon interaction studied with PANDA provides crucial tests in this area. Furthermore, the high-intensity, low-energy domain of PANDA allows for searches for physics beyond the Standard Model, e.g. through high precision symmetry tests. This paper takes into account a staged approach for the detector setup and for the delivered luminosity from the accelerator. The available detector setup at the time of the delivery of the first antiproton beams in the HESR storage ring is referred to as the Phase One setup. The physics programme that is achievable during Phase One is outlined in this paper.