Infrared complex refractive index of N-containing astrophysical ices free of water processed by cosmic-ray simulated in laboratory

Author(s)

Rocha, W. R. M. ^{[1, 2, 3]} ; Pilling, S. ^{[1, 4]} ; Domaracka, A. ^[5] ; Rothard, H. ^[5] ; Boduch, P. ^[5]

Affiliation

^[1] Univ Vale Paraiba UNIVAP, LASA, Av Shishima Hifumi 2911, BR-12244000 Sao Jose Dos Campos, SP - Brazil

^[2] Univ Copenhagen, Niels Bohr Inst, Oster Voldgade 5-7, DK-1350 Copenhagen K - Denmark

^[3] Univ Copenhagen, Ctr Star & Planet Format, Oster Voldgade 5-7, DK-1350 Copenhagen K - Denmark

^[4] ITA, DCTA, Dept Fis, BR-12228900 Sao Jose Dos Campos, SP - Brazil

^[5] Normandie Univ, Ctr Rech Ions Mat & Photon, CEA, ENSICAEN, UNICAEN, CNRS, CIMAP, F-14000 Caen - France

• Document type: Journal article
• Source: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY; v. 228, MAR 5 2020.
• Web of Science Citations: 0

Abstract

Several nitrogen-containing molecules have been unambiguously identified in the Solar System and in the Interstellar Medium. It is believed that such a rich inventory of species is a result of the energetic processing of astrophysical ices during the interaction with ionizing radiation. An intrinsic parameter of matter, the complex refractive index, stores all the ``chemical memory{''} triggered by energetic processing, and therefore might be used to probe ice observations in the infrared. In this study, four N-containing ices have been condensed in an ultra-high vacuum chamber and processed by heavy ions (O and Ni) with energies between 0.2 and 15.7 MeV at the Grand Accelerateur National d'Ions Lourds (GANIL), in Caen, France. All chemical changes were monitored in situ by Infrared Absorption Spectroscopy. The complex refractive index was calculated directly from the absorbance spectrum, by using the Lambert-Beer and Kramers-Kroning relations, and the values are available in an online database: https://www1.univap.br/gaa/nkabs-database/data.htm. As a result, other than the database, it was observed that non-polar ices are more destroyed by sputtering than polar ones. Such destruction and chemical evolution lead to variation in the IR albedo of samples addressed in this paper. (c) 2019 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 16/11334-5 - Experimental simulation of the effects of energetic particles (ions and electrons) on the surface of icy bodies in the Solar System: physicochemical transformation of ices mixtures containing H2O,CO2,CH4 (10:1:1)
• Grantee: Marina Gomes Rachid
• Support Opportunities: Scholarships in Brazil - Master
• FAPESP's process: 16/22018-7 - Production of complex organic molecules on Solar System icy moons induced by swift ions (cosmic ray analogs).
• Grantee: Sergio Pilling Guapyassu de Oliveira
• Support Opportunities: Scholarships abroad - Research
• FAPESP's process: 13/07657-5 - Computational modeling of circumstellar environment of protostars by employing data of bombarded ices with cosmic rays simulated in laboratory.
• Grantee: Will Robson Monteiro Rocha
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 17/07283-9 - Processing of warm ices by low energy ions: probing the effects of solar wind and low energy magnetospheric ions on frozen Solar System bodies
• Grantee: Marina Gomes Rachid
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree