Whitworth, Anthony Peter ![]() |
Abstract
It is assumed that grains can only nucleate in stellar mass loss events. Hence, the only carbon which can contribute to graphite nuclei is 'virgin' carbon, i.e. carbon which was overabundant relative to oxygen in its last mass-loss event. Models for the evolution of elemental abundances in the interstellar medium predict that virgin carbon constitutes at most about 10 percent of the total interstellar carbon. Thus, unless graphite nuclei can grow significantly by selective accretion in interstellar space, there is probably not enough graphite to explain the 2175-A peak in the extinction curve. It is also shown that secondary nitrogen formed from carbon seed nuclei can appear primary relative to oxygen, and that Larson's (1986) prescription for bimodal star formation can only produce the mass of dark remnants he requires at the expense of producing too much metallicity.
Item Type: | Conference or Workshop Item (Paper) |
---|---|
Date Type: | Publication |
Status: | Published |
Schools: | Physics and Astronomy |
Subjects: | Q Science > QB Astronomy |
Publisher: | Cambridge University Press |
ISBN: | 9780521355803 |
Last Modified: | 28 Oct 2022 09:27 |
URI: | https://orca.cardiff.ac.uk/id/eprint/74581 |
Actions (repository staff only)
![]() |
Edit Item |