نوع مقاله : مقاله پژوهشی

نویسنده

1. پژوهشکده‌ی لیزر و اپتیک، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی 2. گروه فیزیک، دانشکده‌ی علوم پایه، دانشگاه تربیت مدرس

چکیده

سازوکار شتاب­دهی پروتون از غلاف تشکیل شده در پشت هدف آلومینیم در برهم­کنش لیزر با قطبش P، با پهنای زمانی fs 40 < و شدت Wcm-2  3.6×1019به طور تجربی و شبیه­سازی مطالعه شده است.نتایج نشان دادند که انرژی ماکزیمم و هم­چنین تعداد پروتون­های شتاب گرفته با اِعمال چِرپ مثبت در مقایسه با حالت برهم­کنش بدون چِرپ و چِرپ منفی افزایش می­یابد. سپس فرایند گرم شدن الکترون­ها در برهم­کنش با پالس لیزر با چِرپ مثبت و منفی بررسی، و رابطه­ی بین پارامتر چِرپ و میدان الکترواستاتیکی تولید شده در پشت هدف مطالعه شده است. نتایج شبیه­سازی نشان دادند که در برهم­کنش لیزر با چِرپ مثبت در مقایسه با چِرپ منفی و حالت بدون چِرپ، فرایند گرم شدن الکترون­ها و هم­چنین میدان الکتریکی ایجاد شده به منظور شتاب­دهی پروتون­ها، افزایش چشم­گیری می­یابد.

کلیدواژه‌ها

عنوان مقاله [English]

Proton Acceleration Enhancement in Frequency Chirped Laser Pulse Interaction with Plasma

نویسنده [English]

  • E Yazdani

چکیده [English]

Proton acceleration process by the generated sheath in the rear-side of an Al target in the interaction of P polarized laser with the pulses duration of  ≥40 fs and intensity of 3.6×1019 W cm-2 has been experimentally and  numerically studied. The results show that by employing the positively chirped pulse, the proton cut off energy and the number of the accelerated protons are increaesd in comparison with an unchirped and negatively chirped pulse interactions. After that, the electron heating process in interaction of positivly and negativly chirped  pulse is investigated and correlation between the chirped parameter and produced electrostatic field in the backside of the target is studied. Particle- in-cell simulation results show that the electron heating process and consequently the electrostatic field for proton acceleration goal are significantly increased by employing the positively chirped pulse campared to negativly unchirped conditions.

کلیدواژه‌ها [English]

  • Laser Plasma Interaction
  • Proton Acceleration
  • Simulation
  • Chirp

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