Survival of gas phase amino acids and nucleobases in space radiation conditions

• Published in: arXiv.org
• Main Authors: Pilling, S, Andrade, D P P, de Castilho, R B, Cavasso-Filho, R L, Lago, A F, Coutinho, L H, G G B de Souza, Boechat-Roberty, H M, A Naves de Brito
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 26.03.2008
• Subjects: Amino acids; Comets; Extraterrestrial radiation; High vacuum; Interstellar matter; Ions; Mass spectra; Photodissociation; Photoelectrons; Photoionization; Photons; Physics - Astrophysics of Galaxies; Physics - Cosmology and Nongalactic Astrophysics; Physics - Earth and Planetary Astrophysics; Physics - High Energy Astrophysical Phenomena; Physics - Instrumentation and Methods for Astrophysics; Physics - Solar and Stellar Astrophysics; Polycyclic aromatic hydrocarbons; Soft x rays; Stellar radiation; Survival; Vapor phases
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.0803.3751

We present experimental studies on the photoionization and photodissociation processes (photodestruction) of gaseous amino acids and nucleobases in interstellar and interplanetary radiation conditions analogs. The measurements have been undertaken at the Brazilian Synchrotron Light Laboratory (LNLS), employing vacuum ultraviolet (VUV) and soft X-ray photons. The experimental set up basically consists of a time-of-flight mass spectrometer kept under high vacuum conditions. Mass spectra were obtained using photoelectron photoion coincidence technique. We have shown that the amino acids are effectively more destroyed (up to 70-80%) by the stellar radiation than the nucleobases, mainly in the VUV. Since polycyclic aromatic hydrocarbons have the same survival capability and seem to be ubiquitous in the ISM, it is not unreasonable to predict that nucleobases could survive in the interstellar medium and/or in comets, even as a stable cation.