نوع مقاله : مقاله پژوهشی
نویسندگان
پژوهشکده پلاسما و گداخت هسته‌ای، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی، صندوق پستی: 51113-14399، تهران- ایران
چکیده
در این کار، ابتدا یک پلاسمای میکروموج آرگون با فرکانس 45/2 گیگا هرتز در فشار پایین به صورت تجربی به‌دست می‌آید. سپس سعی میشود مشخصات پلاسمای تشکیل شده (دما و چگالی الکترونها) در حضور و بدون حضور میدان مغناطیسی با استفاده از بیناب‌نمایی نشر نوری محاسبه و مقایسه شود. از آهنرباهای دایمی جهت محصورسازی پلاسما و تأمین میدان مغناطیسی در مکانیزم تشدید سیکلوترونی الکترونی استفاده شده و به کمک شبیهسازی، چیدمان مناسب آهن‌رباها برای تولید میدان مغناطیسی مورد نظر به‌دست می‌آید. در ادامه با استفاده از مدلهای فیزیکی مربوطه، دما و چگالی الکترونها محاسبه میشود. نتایج به‌دست آمده نشان می‌دهد میدان مغناطیسی اثر
قابل توجه روی مشخصات پلاسما داشته و حدود 125 درصد افزایش دما و 200 درصد افزایش چگالی الکترونها را در پی دارد. هم‌چنین نشان داده میشود طبق انتظار با کاهش فشار، دمای الکترونها افزایش و چگالی آن ها کاهش مییابد که این، صحت آزمایش و نتایج به‌دست آمده را تأیید میکند.
کلیدواژه‌ها
عنوان مقاله [English]
Characterization of microwave source plasma in the presence of a magnetic field caused by a permanent magnet
نویسندگان [English]
- Z. Dehghani
- E. Khalilzadeh
- N Razavinia
- A. Chakhmachi
Plasma and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, AEOI, P.O. Box: 14399-51113, Tehran - Iran
چکیده [English]
In this work, an argon microwave plasma with a frequency of 2.45 GHz at low pressure is experimentally demonstrated. Then, the characteristics of the formed plasma (temperature and density of electrons) in the presence and without the presence of a magnetic field are calculated and compared by optical emission spectroscopy. Permanent magnets are used to confine the plasma and supply the magnetic field in the electron cyclotron resonance mechanism. With the help of simulation, the proper arrangement of the magnets to produce the desired magnetic field is obtained. Then, using the relevant physical models, the temperature and density of the electrons are calculated. The results show that the magnetic field has a significant effect on the plasma characteristics and causes about 125% increase in temperature and 200% increase in electron density. It is also shown that, as expected, as the pressure decreases, the temperature of the electrons increases and their density decreases. This confirms the accuracy of the experiment and the obtained results
کلیدواژه‌ها [English]
- Microwave plasma
- Plasma characterization
- Electron cyclotron resonance mechanism
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