English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

We present a new Spitzer Infrared Spectrograph (IRS) spectrum of the carbon star IRAS 04496-6958 in the Large Magellanic Cloud, which exhibits a fairly broad absorption feature at ~11 μm. This feature is consistent with SiC absorption, as seen in a few Galactic sources. Furthermore, the C2H2 (and other molecular) absorption bands are the deepest ever observed, indicative of a very high column density. While the Galactic sources with SiC absorption have cool colors (continuum temperature ≈300 K), IRAS 04496-6958 is much bluer, with a continuum temperature of ≈600 K. Based on the Galactic sample, SiC dust at this temperature should still display an emission feature at ~11 μm. If SiC is the cause of the absorption feature, it suggests a subtly different evolutionary path and a change to a different condensation sequence than assumed for Galactic carbon stars. An alternative explanation for this feature is molecular line absorption; however, currently available line lists are not sufficient to properly assess this hypothesis.

The UnusualSpitzerSpectrum of the Carbon Star IRAS 04496−6958: A Different Condensation Sequence in the LMC?