Description
The chemistry expected to take place in astrophysical ice mantles exposed to radiation and cosmic rays, and also the physical processes such us desorption, must be influenced by the intrinsic ice properties. Among the physical properties of relevance are the ice density, the amorphous/crystalline ice structure, and the ice optical constants. We developed a method to measure the propagation of ultrasonic pulses through the ice, aiming to estimate the net porosity of ice samples grown under different conditions. The porosity of ice mantles in interstellar and circumstellar regions is a relevant and yet unknown ice property that affects the chemistry. Indeed, due to its large effective surface, a highly porous water-dominated ice is expected to enhance chemical reactions with other species and radicals hosted in the micropores upon energetic processing of the ice. Our experimental configuration and first results will be presented.
