Molecular synthesis in hypervelocity impact plasmas on the primitive Earth and in interstellar clouds
Molecular synthesis in hypervelocity impact plasmas on the primitive Earth and in interstellar clouds
复制标题
超高速冲击等离子体中的分子合成原始地球和星际云
DOI：
--
复制
发表时间：
2003
期刊：
影响因子：
--
通讯作者：
A. Chumikov
中科院分区：
文献类型：
--
作者：
G. Managadze;W. Brinckerhoff;A. Chumikov
当撞击速度超过15-20 km s-1的临界范围时，产生的等离子体羽流非常迅速地从几个eV激发，当速度达到50-100 km s-1时高达30-50 eV，并且可以完全雾化和电离。在撞击后绝热扩散期间，电离度下降。剩下的离子主要是原子，采样碰撞体的元素组成，但也形成了一些分子离子。我们在这里介绍的实验结果，其中的物理和化学条件的羽状物的超高速微陨石的影响远远超过20公里的s-1的模拟与Q开关激光烧蚀。使用能够区分等离子体合成与表面解吸物质的飞行时间（TOF）质量反射器分析形成的分子离子。单电荷和多电荷有机小分子被确定为在无机含碳物质诱导的激光等离子体中形成。结果表明，在重轰击期间流星对原始地球的超高速撞击和星际云中的尘埃粒子的超高速撞击中，有机分子的非生物合成是可能的。
When impact speeds exceed a critical range of ∼15–20 km s−1, the resulting plasma plume energizes very rapidly from a few eV, to as high as 30–50 eV when speeds reach 50–100 km s−1, and can be completely atomized and ionized. During post‐impact adiabatic dispersion, the degree of ionization drops. The remaining ion population is mostly atomic, sampling the elemental composition of the colliding bodies, but some molecular ions are also formed. We present here results of experiments in which the physical and chemical conditions in the plume of a hypervelocity micrometeorite impact well above 20 km s−1 were modeled with Q‐switched laser ablation. The formed molecular ions were analyzed with a time‐of‐flight (TOF) mass reflectron capable of distinguishing plasma‐synthesized from surface‐desorbed species. Singly‐ and multiply‐charged small organic molecules were identified as having formed in laser plasmas induced from inorganic carbonaceous substances. The results show the possibility of abiogenic synthesis of organic molecules in hypervelocity impacts of meteors on the primitive Earth during heavy bombardment and of dust particles in interstellar clouds.