Irradiation of Condensed Gases by Fast Ions: Physical Mechanisms and Astrophysical Implications

有许多天体物理现象的例子，其中关于带电粒子轰击冰的影响的知识至关重要。银河系中的宇宙射线粒子改变了凝结在星际冰粒外壳上的气体和有机物。太阳风和太阳耀斑中的离子在太阳系演化的早期阶段轰击冰粒和冰冷物质，改变了这些物质的化学性质，然后聚集形成彗星等物体。外行星磁层中的等离子体离子的轰击会改变这些行星卫星和光环表面的光谱特性。有了这笔赠款，弗吉尼亚大学的约翰逊和枯燥博士将与AT&P；T贝尔实验室的同事合作，继续他们的实验室研究，研究高能带电粒子轰击冰层表面时产生的光谱和化学性质的变化。实验结果将用于了解星际介质中冰粒的光谱变化和大分子的产生，外行星卫星和环表面的修改，以及长期离子轰击对彗星碎片和彗前物质的影响。

There are numerous examples of astrophysical phenomena where knowledge of the effect of bombardment of ices by charged particles is crucial. Cosmic ray particles in the Galaxy modify gases and organics which are condensed on the mantles of interstellar ice grains. Ions in the solar wind and from solar flares, which bombarded ice grains and icy materials in the early stages of the evolution of the Solar System, altered the chemical nature of those materials which then accreted to form objects such as comets. Bombardment by plasma ions in the magnetospheres of the outer planets can alter the spectral characteristics of the surfaces of the satellites and rings of these planets. With this grant, Drs. Johnson and Boring, at the University of Virginia, in collaboration with colleagues at AT&T Bell Laboratories will continue their laboratory study of the changes produced in the spectral and chemical properties of icy surfaces when bombarded by energetic, charged particles. The experimental results will be used to understand the spectral alteration of icy grains and the production of large molecules in the interstellar medium, the modification of the surfaces of the satellites and rings of the outer planets, and the effect of long term ion bombardment on cometary debris and pre-cometary materials.