1. Radioresistance of Adenine to Cosmic Rays
- Author
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Alicja Domaracka, R. Martinez, B. Augé, Christian F Mejía, Hermann Rothard, Gabriel S. Vignoli Muniz, Philippe Boduch, Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Federal University of Amapà, Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Astrochemistry ,010504 meteorology & atmospheric sciences ,Spectrophotometry, Infrared ,Cosmic ray ,01 natural sciences ,Ionizing radiation ,Nucleobase ,Ion ,0103 physical sciences ,Stopping power (particle radiation) ,Heavy Ions ,Irradiation ,Spectroscopy ,010303 astronomy & astrophysics ,0105 earth and related environmental sciences ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,Chemistry ,Adenine ,Radiochemistry ,Ice ,Temperature ,Water ,Agricultural and Biological Sciences (miscellaneous) ,13. Climate action ,Space and Planetary Science ,ddc:520 ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Cosmic Radiation - Abstract
International audience; The presence of nucleobases in carbonaceous meteorites on Earth is an indication of the existence of this class of molecules in outer space. However, space is permeated by ionizing radiation, which can have damaging effects on these molecules. Adenine is a purine nucleobase that amalgamates important biomolecules such as DNA, RNA, and ATP. Adenine has a unique importance in biochemistry and therefore life. The aim of this work was to study the effects of cosmic ray analogues on solid adenine and estimate its survival when exposed to corpuscular radiation.Adenine films were irradiated at GANIL (Caen, France) and GSI (Darmstadt, Germany) by 820 MeV Kr33+, 190 MeV Ca10+, 92 MeV Xe23+, and 12 MeV C4+ ion beams at low temperature. The evolution of adenine molecules under heavy ion irradiation was studied by IR absorption spectroscopy as a function of projectile fluence.It was found that the adenine destruction cross section (σd) follows an electronic stopping power (Se) power law under the form: CSen; C is a constant, and the exponential n is a dimensionless quantity. Using the equation above to fit our results, we determined σd = 4 × 10−17Se1.17, with Se in kiloelectronvolts per micrometer (keV μm−1). New IR absorption bands arise under irradiation of adenine and can be attributed to HCN, CN-, C2H4N4, CH3CN, and (CH3)3CNC.These findings may help to understand the stability and chemistry related to complex organic molecules in space. The half-life of solid adenine exposed to the simulated interstellar medium cosmic ray flux was estimated as (10 ± 8) × 106 years. Key Words: Heavy ions—Infrared spectroscopy—Astrochemistry—Cosmic rays—Nucleobases—Adenine. Astrobiology 17, 298–308.
- Published
- 2017