نوع مقاله : مقاله پژوهشی

نویسندگان

1 پژوهشکده فیزیک و شتابگرها، پژوهشگاه علوم فنون هسته‌ای، سازمان انرژی اتمی، صندوق پستی: 8486-11365، تهران- ایران

2 دانشکده فیزیک و انرژی، دانشگاه امیرکبیر، صندوق پستی: 4413-15875، تهران- ایران

چکیده

در این مقاله پلاسمای چشمه یونی کوچک مقیاس تشدید سیکلوترونی الکترون آهنربا دائم با فرکانس 45/2 گیگاهرتز شبیه‌سازی و بررسی شده است. این چشمه با محفظه پلاسما به شعاع 50 میلی‌متر، طول 50 میلی‌متر و بیشینه توان ورودی 1 کیلووات، مولد جریان باریکه پروتونی 10 میلی‌آمپر با انرژی 50 کیلوولت است. به دلیل ابعاد کوچک مقیاس محفظه و طول موج بلند میکروموج (mm 4/122= ˳λ) تزریق شده در این چشمه، انتشار و انتقال میکروموج به داخل محفظه در شرایط عادی امکان‌پذیر نمی‌باشد. برای انتقال توان میکروموج به داخل محفظه و تشکیل پلاسما، دی‌الکتریک با جنس آلومینا با ضریب‌گذردهی نسبی 9 در ورودی محفظه استفاده شده است. این مقاله، به طراحی و شبیه‌سازی خط انتقال و جفت شدگی میکروموج به محفظه چشمه یونی کوچک مقیاس پرداخته است. در این راستا، شدت میدان مغناطیسی پیچه‌ها، میدان الکتریکی میکروموج و تحولات زمانی و مکانی کمیت‌های مهم هم‌چون، چگالی توان جذبی، لایه تشدید هیبرید بالا، چگالی و دمای الکترونی در زمان‌های اولیه تزریق میکروموج به داخل چشمه یونی پلاسما مورد ارزیابی قرار گرفته است.

کلیدواژه‌ها

عنوان مقاله [English]

Simulation study of the over dense plasma in an electron cyclotron resonance miniature ion source

نویسندگان [English]

  • H.R. Mirzaei 1
  • M. Yarmohammadi Satri 1
  • H. Rahimpour 1
  • S. Fasih 2

1 Physics and Accelerators Research School, Nuclear Science and Technology Research Institute, AEOI, P.O.Box:11365-8486, Tehran - Iran

2 Department of the Energy Engineering and Physics, Amirkabir University of Technology, P.O.Box: 15875-4413, Tehran - Iran

چکیده [English]

In this paper, the plasma of a 2.45 GHz permanent magnet miniature ECR ion source has been simulated and discussed. The source with a cylindrical plasma chamber of 50 mm in radius, 50 mm in length, and a maximum input power of 1kW generates a 10 mA, 50 kV proton beam. Considering the long wavelength of the microwave generator (λ0 = 122.4 mm) and the miniature size of the plasma chamber, an alumina window with a relative permittivity of 9 is hired at the entrance of the plasma chamber. Microwave power is injected into the chamber through the window. Microwave power transfer and coupling to the miniaturized plasma chamber of the ion source is the focus of this study. In this way, the strength of the magnetic field, microwave electric field, and spatial and temporal variations of the essential parameters like the density of the microwave power absorption, the Upper Hybrid Resonance (UHR) layer, density, and temperature of the plasma at the starting time of the microwave injection to the ion source chamber are investigated.

کلیدواژه‌ها [English]

  • Miniature ion source
  • Electron cyclotron resonance
  • Plasma
  • COMSOL software
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