Titre :

Characterization of interstellar carbon dust analogues synthesized by dielectric barrier discharge and evolution after irradiation with 3 MeV H+

Auteur(s) :

Gerber, Ioana Cristina [Auteur]
Mihaila, Ilarion [Auteur]
Alexandru Ioan Cuza University of Iași = Universitatea Alexandru Ioan Cuza din Iași [UAIC]
Pohoata, Valentin [Auteur]
Sandu, Andrei [Auteur]
Agheorghiesei, Catalin [Auteur]
Soroaga, Laurentiu Valentin [Auteur]
Iancu, Decebal [Auteur]
Horia Hulubei National Institute of Physics and Nuclear Engineering [NIPNE]
Andrei, Radu Florin [Auteur]
Burducea, Ion [Auteur]
Horia Hulubei National Institute of Physics and Nuclear Engineering [NIPNE]
Straticiuc, Mihai [Auteur]
Duca, Dumitru [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Egorov, Dmitrii [Auteur]
Physique Moléculaire aux Interfaces [PMI]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Carpentier, Yvain [Auteur]
Physique Moléculaire aux Interfaces [PMI]
Chazallon, Bertrand [Auteur]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Physique Moléculaire aux Interfaces [PMI]
Faccinetto, Alessandro [Auteur]
Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 [PC2A]
Nuns, Nicolas [Auteur]
Institut Michel Eugène Chevreul - FR 2638 [IMEC]
Focsa, Cristian [Auteur]
Physique Moléculaire aux Interfaces [PMI]
Pirim, Claire [Auteur]
Centre d'Etudes et de Recherches Lasers et Applications [CERLA]
Physique Moléculaire aux Interfaces [PMI]
Laboratoire de Physique des Lasers, Atomes et Molécules - UMR 8523 [PhLAM]
Topala, Ionut [Auteur]

Titre de la revue :

Monthly Notices of the Royal Astronomical Society

Pagination :

266-279

Éditeur :

Oxford University Press (OUP): Policy P - Oxford Open Option A

Date de publication :

2025-03-28

ISSN :

0035-8711

Discipline(s) HAL :

Physique [physics]/Physique [physics]/Chimie-Physique [physics.chem-ph]

Résumé en anglais : [en]

ABSTRACT ‘Fluffy’ hydrogenated amorphous carbon (a-C:H) was synthesized using a dielectric barrier discharge plasma, driven by nanosecond high voltage pulses at 1 kHz frequency in a helium–butane mixture. The a-C:H samples ...
Lire la suite >ABSTRACT ‘Fluffy’ hydrogenated amorphous carbon (a-C:H) was synthesized using a dielectric barrier discharge plasma, driven by nanosecond high voltage pulses at 1 kHz frequency in a helium–butane mixture. The a-C:H samples were characterized by scanning and transmission electron microscopy, laser-assisted and secondary ion mass spectrometry, and Raman and Fourier-transform infrared spectroscopy. We find that a-C:H samples exhibit infrared absorption features in good agreement with those observed for carbonaceous dust in IRAS 08572 + 3915 galaxy. We discuss their nano- to microscale structure and derive their hydrogen to carbon (H/C) ratios from the results obtained by three distinct experimental characterization techniques. Relying on the average H/C value determined by mass spectrometry and Raman spectroscopy, we can then constrain the absorption strengths values to those best corresponding to our dust analogue, and calculate the H/C ratio from the infrared spectra. Altogether, we find that our dust analogue consists of a dominant hydrogen-rich aliphatic network, with small, isolated, aromatic regions. The a-C:H dust analogue was then irradiated with 3 MeV H+ and subsequently analysed ex situ. Morphological and chemical changes, including the evolution of H/C, CH2/CH3, and sp2/sp3 ratios, were observed with increasing proton fluence, indicating dehydrogenation and graphitization. Proton bombardment shifted the initial location of a-C:H in the hydrocarbon ternary phase diagram toward the central region defined by IRAS 08572 + 3915 observations. The decay of the 3.4 $\mu$m band with proton fluence was used to calculate CH destruction cross-sections, results consistent with a direct effect of cosmic rays on the disappearance of the 3.4 $\mu$m band.Lire moins >

Langue :

Anglais

Comité de lecture :

Oui

Audience :

Internationale

Vulgarisation :

Non

Collections :

• Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) - UMR 8523

Source :

Harvested from HAL

Date de dépôt :

2025-04-04T02:47:56Z