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arXiv · 1803.01185

Tetrahedral hydrocarbon nanoparticles in space: X-ray spectra

G. Bilalbegovic·A. Maksimovic·L. A. Valencic
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Abstract

It has been proposed, or confirmed, that diamond nanoparticles exist in various environments in space: close to active galactic nuclei, in the vicinity of supernovae and pulsars, in the interior of several planets in the Solar system, in carbon planets and other exoplanets, carbon-rich stars, meteorites, in X-ray active Herbig Ae/Be stars, and in the interstellar medium. Using density functional theory methods we calculate the carbon K-edge X-ray absorption spectrum of two large tetrahedral nanodiamonds: C26H32 and C51H52. We also study and test our methods on the astrophysical molecule CH4, the smallest C-H tetrahedral structure. A possible detection of nanodiamonds from X-ray spectra by future telescopes, such as the project Arcus, is proposed. Simulated spectra of the diffuse interstellar medium using Cyg X-2 as a source show that nanodiamonds studied in this work can be detected by Arcus, a high resolution X-ray spectrometer mission selected by NASA for a Phase A concept study.

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G. Bilalbegovic, A. Maksimovic, L. A. Valencic. 2018-03-03. Tetrahedral hydrocarbon nanoparticles in space: X-ray spectra. https://doi.org/10.1093/mnras%2Fsty607

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