We have studied the effects of the substrate, namely amorphous olivine (MgFeSiO4) cosmic dust analogues (CDAs), in synthesis of molecules obtained after 200 keV proton irradiation of formamide (NH2COH). Formamide has been deposited on the olivine substrate at 20 K. The abundances of new molecular species formed after an irradiation dose of 12 eV/16 amu in formamide pure (i.e. deposited on an inert silicon substrate) and deposited on CDAs have been compared. Specifically, MgFeSiO4 amorphous olivine is a selective catalyst preventing formation of NH3 and CN- molecules and changing the relative abundances of {text{NH}}^{ + }4 {text{OCN}}^{ - } , CO2, HNCO, CO. We have shown that the role of CDAs has to be taken into account in experiments simulating processes occurring in astronomical environments.
Cryogenic Synthesis of Molecules of Astrobiological Interest: Catalytic Role of Cosmic Dust Analogues
ROTUNDI, Alessandra;
2006-01-01
Abstract
We have studied the effects of the substrate, namely amorphous olivine (MgFeSiO4) cosmic dust analogues (CDAs), in synthesis of molecules obtained after 200 keV proton irradiation of formamide (NH2COH). Formamide has been deposited on the olivine substrate at 20 K. The abundances of new molecular species formed after an irradiation dose of 12 eV/16 amu in formamide pure (i.e. deposited on an inert silicon substrate) and deposited on CDAs have been compared. Specifically, MgFeSiO4 amorphous olivine is a selective catalyst preventing formation of NH3 and CN- molecules and changing the relative abundances of {text{NH}}^{ + }4 {text{OCN}}^{ - } , CO2, HNCO, CO. We have shown that the role of CDAs has to be taken into account in experiments simulating processes occurring in astronomical environments.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
