Abstract Alpha-decay propulsion technology, a microthrust technology based on thin spontaneous-alpha-decay films, is proposed in this paper. A large quantity of decayed alpha particles emitted from the upper surface of thin films would generate thrust statistically. Simulations were executed using the Monte Carlo N-Particle Transport Code (MCNP) to acquire the energy and angular distributions of escaping alpha particles, as well as the key parameters of alpha-decay films. A 22.40-μm 210Po film combined with a 20-μm aluminum film was able to generate an average thrust of 29.5 nN/cm2 in half-life time. The remaining charges and thermal energies of the decay films were considered. Directional-generated alpha particles were simulated to analyze the influence of angular scattering on escaped alpha-particle distributions. Alpha particles with low energy, with large scattering angles, or with large generated angles contributed less to thrust value. With the assumptions of no scattering, constant stopping power, and no range struggling, a set of analytic formulas were derived. Comparisons of the distributions and typical parameters between simulations and the analytic model were conducted. Discrepancies were mostly caused by the three assumptions and were less than 3.7% for thrust and less than 3.9% for the proportion of escaped alpha-particles.

中文翻译：

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一种基于自发α衰变的核衰变微推进技术

摘要 本文提出了一种基于自发α衰变薄膜的微推力技术——α衰变推进技术。大量从薄膜上表面发射的衰变α粒子会产生统计推力。使用蒙特卡罗 N 粒子传输代码 (MCNP) 执行模拟，以获取逃逸 alpha 粒子的能量和角度分布，以及 alpha 衰变膜的关键参数。22.40-μm 210Po 薄膜与 20-μm 铝薄膜结合能够在半衰期内产生 29.5 nN/cm2 的平均推力。考虑了衰变膜的剩余电荷和热能。模拟定向生成的 alpha 粒子以分析角散射对逃逸的 alpha 粒子分布的影响。低能量的阿尔法粒子，大的散射角或大的产生角对推力值的贡献较小。在无散射、恒定制动力、无距离挣扎的假设下，推导出一组解析公式。对模拟和解析模型之间的分布和典型参数进行了比较。差异主要由三个假设引起，推力小于 3.7%，逃逸的 α 粒子比例小于 3.9%。