Discrete and Continuous Models and Applied Computational ScienceDiscrete and Continuous Models and Applied Computational ScienceDiscrete and Continuous Models and Applied Computational Science2658-46702658-7149Peoples' Friendship University of Russia named after Patrice Lumumba (RUDN University)3220310.22363/2658-4670-2022-30-3-217-230ArticlesСтатьиResearch ArticleNumerical simulation of cold emission in coaxial diode with magnetic isolationЧисленное моделирование холодной эмиссии в коаксиальном диоде с магнитной изоляциейhttps://orcid.org/0000-0002-0918-9263BelovAlexandr A.БеловА. А.

Candidate of Physical and Mathematical Sciences, Researcher of Faculty of Physics, M. V. Lomonosov Moscow State University; Assistant professor of Department of Applied Probability and Informatics of Peoples’ Friendship University of Russia

aa.belov@physics.msu.ruhttps://orcid.org/0000-0003-4676-6303LozaOleg T.ЛозаО. Т.

Doctor of Physical and Mathematical Sciences, Professor of Institute of Physical Research and Technology

loza-ot@rudn.ruhttps://orcid.org/0000-0002-3645-1060LovetskiyKonstantin P.ЛовецкийК. П.

Candidate of Physical and Mathematical Sciences, Associate professor of Department of Applied Probability and Informatics

lovetskiy-kp@rudn.ruhttps://orcid.org/0000-0001-5696-1546KarnilovichSergey P.КарниловичС. П.

Candidate of Physical and Mathematical Sciences, Assistant professor of Institute of Physical Research and Technology

karnilovich-sp@rudn.ruhttps://orcid.org/0000-0002-1856-4643SevastianovLeonid A.СевастьяновЛ. А.

Doctor of Physical and Mathematical Sciences, Professor of Department of Applied Probability and Informatics

sevastianov-la@rudn.ruLomonosov Moscow State UniversityМосковский государственный университет им. М.В. ЛомоносоваPeoples’ Friendship University of Russia (RUDN University)Российский университет дружбы народов05102022303VOL 30, NO3 (2022)ТОМ 30, №3 (2022)21723005102022Copyright ©; 2022, Belov A.A., Loza O.T., Lovetskiy K.P., Karnilovich S.P., Sevastianov L.A.Copyright ©; 2022, Белов А.А., Лоза О.Т., Ловецкий К.П., Карнилович С.П., Севастьянов Л.А.2022Belov A.A., Loza O.T., Lovetskiy K.P., Karnilovich S.P., Sevastianov L.A.Белов А.А., Лоза О.Т., Ловецкий К.П., Карнилович С.П., Севастьянов Л.А.https://creativecommons.org/licenses/by-nc/4.0https://journals.rudn.ru/miph/article/view/32203

Due to the emergence and active development of new areas of application of powerful and super-powerful microwave vacuum devices, interest in studying the behavior of ensembles of charged particles moving in the interaction space has increased. An example is an electron beam formed in a coaxial diode with magnetic isolation. Numerical simulation of emission in such a diode is traditionally carried out using particle-in-cell methods. They are based on the simultaneous calculation of the equations of motion of particles and the Maxwell’s equations for the electromagnetic field. In the present work, a new computational approach called the point macroparticle method is proposed. In it, the motion of particles is described by the equations of relativistic mechanics, and explicit expressions are written out for fields in a quasi-static approximation. Calculations of the formation of a relativistic electron beam in a coaxial diode with magnetic isolation are performed and a comparison is made with the known theoretical relations for the electron velocity in the beam and for the beam current. Excellent agreement of calculation results with theoretical formulas is obtained.

В связи с появлением и активным развитием новых областей применения мощных и сверхмощных электровакуумных приборов СВЧ возрос интерес к изучению особенностей поведения ансамблей заряженных частиц, движущихся в пространстве взаимодействия. Примером является пучок электронов, формируемый в коаксиальном диоде с магнитной изоляцией. Численное моделирование эмиссии в таком диоде традиционно проводится с помощью методов типа «частица в ячейке». Они основаны на одновременном расчете уравнений движения частиц и уравнений Максвелла для электромагнитного поля. В данной работе предложен новый вычислительный подход, названный методом точечных макрочастиц. В нем движение частиц описывается уравнениями релятивистской механики, а для полей выписываются явные выражения в квазистатическом приближении. Выполнены расчеты формирования релятивистского электронного пучка в коаксиальном диоде с магнитной изоляцией и проведено сравнение с известными теоретическими соотношениями для скорости электронов в пучке и для тока пучка. Получено отличное согласование результатов расчета с теоретическими формулами.

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