Search

In a mixture of molecular gases with compositions (CO2–N2–H2O and CO–N2–H2O) and total pressure close to that of the Earth’s early atmospheres, a centimeter-sized plasma was created by focusing a single 85-J, 450-ps near-infrared laser pulse in a center of 15-L gas cell. Chemical consequences of the laser-produced plasma generation in such a mixture were investigated using high-performance liquid chromatography with mass-spectrometric detection (HPLC/MS). Amino acids were identified in the reaction mixture containing CO2 as well as in that one based on CO, both exposed to 10 laser shots. [Copyright &y& Elsevier]

Abstract: A large-scale plasma was created in CO–N2–H2O gas mixtures by high-power laser-induced dielectric breakdown. The composition of the mixtures used corresponded to a cometary and/or meteoritic impact into the Earth’s early atmosphere. A multiple-centimeter-sized fireball was created by focusing near-infrared laser pulse into the centre of cell. The laser–plasma formation in the mixtures mainly leads to a production of CO2. The competition of the CO+CO→CO2 +C and CO+OH→CO2 +H reactions in the CO2 production was investigated using 18O labeled water. An analysis of the isotopomers was carried out by means of high-resolution FTIR spectroscopy. [Copyright &y& Elsevier]