تحریک و تقویت مُدهای هیبریدی در موجبرهای پلاسمایی ترکیبی دایروی- بیضوی شامل باریکه الکترونی نسبیتی

نوع مقاله : مقاله پژوهشی

نویسندگان

1 دانشجوی دکترا، دانشکده فیزیک، دانشگاه کاشان، کاشان، ایران

2 استادیار، دانشکده فیزیک، دانشگاه کاشان، کاشان، ایران

3 دانشیار، دانشکده فیزیک، دانشگاه کاشان، کاشان، ایران

چکیده

معادله پاشندگی و نرخ رشد امواج الکترومغناطیسی هیبریدی منتشره در دو نوع موجبر ترکیبی با دیواره رسانای کامل شامل ستون پلاسمای سرد همسانگرد که توسط باریکه الکترونی نسبیتی تغذیه می‏شوند، مورد مطالعه قرار می‏گیرد. دیواره رسانای موجبر نخست دارای سطح مقطع بیضوی است که ستون پلاسما با مقطع دایره در مرکز آن قرار گرفته و بقیه نواحی داخلی از مرز پلاسما تا مرز موجبر با ماده دی‏الکتریک پر شده است. اما موجبر دوم دارای سطح مقطع دایروی است که ستون پلاسمای بیضوی در مرکز آن قرار گرفته است. باریکه‏های الکترونی بعنوان چشمه انرژی بصورت هم محور با ستون پلاسما به داخل آن تزریق می‏شوند. با محاسبه مؤلفه‏های میدان‏های الکترومغناطیسی در هر یک از نواحی پیکربندی های مورد مطالعه و اعمال شرایط مرزی، فرکانس کار و نرخ رشد بدست می‏آیند. نتایج محاسبات عددی به صورت نمودار ارائه می‏گردد.

کلیدواژه‌ها


عنوان مقاله [English]

Excitation and amplification of hybrid modes in circular-elliptic combined plasma waveguides including relativistic electron beam

نویسندگان [English]

  • Moslem Alizadehfar 1
  • Zeinab Rahmani 2
  • Abbas Abdoli Arani 3
1 PhD student, Faculty of Physics, Kashan University, Kashan, Iran
2 Assistant Professor, Faculty of Physics, Kashan University, Kashan, Iran
3 Associate Professor, Faculty of Physics, Kashan University, Kashan, Iran
چکیده [English]

The dispersion relation and the growth rate of the hybrid electromagnetic waves propagating in the two types of combined waveguides with complete conductor walls including isotropic cold plasma column that powered by relativistic electron beam, have been studied.The conducting wall cross section of the first waveguide is elliptical that plasma column with circular cross section is located in its core and the rest of interior regions is filled with dielectric material from the plasma boundary to the waveguide boundary. But the second waveguide has acircular cross section that elliptical plasma column is situated in its center. Electron beams as source energy are injected inside it coaxially with plasma column. By calculation of electromagnetic fields components in each of regions in the considered configurations, applying the boundary conditions, operating frequency and growth rate are obtained. The results of numerical computations are graphically presented.

کلیدواژه‌ها [English]

  • Relativistic electron beam
  • Cold plasma
  • Dispersion relation
  • Combined waveguide
  • Time growth rate

Smiley face

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دوره 11، شماره 1 - شماره پیاپی 26
شماره پیاپی 26، دوفصلنامه بهار و تابستان
خرداد 1402
صفحه 61-73
  • تاریخ دریافت: 10 آذر 1400
  • تاریخ بازنگری: 24 دی 1400
  • تاریخ پذیرش: 15 تیر 1401
  • تاریخ انتشار: 01 خرداد 1402