Files in this item

FilesDescriptionFormat

application/vnd.openxmlformats-officedocument.presentationml.presentation

application/vnd.openxmlformats-officedocument.presentationml.presentation1445613.pptx (9MB)
PresentationMicrosoft PowerPoint 2007

application/pdf

application/pdf3939.pdf (16kB)
AbstractPDF

Description

Title:FORMATION OF INTERSTELLAR C60 FROM SILICON CARBIDE CIRCUMSTELLAR GRAINS
Author(s):Bernal, Jacob
Contributor(s):Amari, Sachiko ; Zega, Thomas J.; Howe, Jane ; Haenecour, Pierre ; Ziurys, Lucy M.
Subject(s):Astronomy
Abstract:The positive detection of buckminsterfullerene (C$_{60}$) in circumstellar and interstellar environments has changed paradigms of chemical complexity in the hostile conditions of space. While C$_{60}$ is a significant sink of interstellar carbon, the formation mechanism is still the subject of speculation. To examine C$_{60}$ formation, we have conducted shock-heating experiments on synthetic, 3C-SiC grains, the most common polytype generated by stars. Measurements of the heated grains, conducted with transmission electron microscopy (TEM) and electron energy-loss spectroscopy (EELS) techniques, show the formation of graphite and carbon nanobuds on the sample surface. The nanobud diameters are nearly identical to that of C$_{60}$, indicating that spherical structures may be forming as well. These data suggest that C$_{60}$ is formed by the shock-heating of common SiC grains at the end of the asymptotic giant branch (AGB) phase. In addition, TEM measurements of actual pre-solar grains extracted from meteorites show a central SiC core, surrounded by graphite, confirming our proposed formation mechanism.
Issue Date:2019-06-19
Publisher:International Symposium on Molecular Spectroscopy
Genre:Conference Paper / Presentation
Type:Text
Language:English
URI:http://hdl.handle.net/2142/104376
DOI:10.15278/isms.2019.WA01
Rights Information:Copyright 2019 Jacob Bernal
Date Available in IDEALS:2019-07-15
2020-01-25


This item appears in the following Collection(s)

Item Statistics