| | |
| | |
Stat |
Members: 3645 Articles: 2'506'133 Articles rated: 2609
27 April 2024 |
|
| | | |
|
Article overview
| |
|
Dust Processing and Grain Growth in Protoplanetary Disks in the Taurus-Auriga Star-Forming Region | B.A. Sargent
; W.J. Forrest
; C. Tayrien
; M.K. McClure
; Dan M. Watson
; G.C. Sloan
; A. Li
; P. Manoj
; C.J. Bohac
; E. Furlan
; K.H. Kim
; J.D. Green
; | Date: |
21 Nov 2008 | Abstract: | Mid-infrared spectra of 65 T Tauri stars (TTS) taken with the Infrared
Spectrograph (IRS) on board the Spitzer Space Telescope are modeled using dust
at two temperatures to probe the radial variation in dust composition in the
uppermost layers of protoplanetary disks. Most spectra indicating crystalline
silicates require Mg-rich minerals and silica, but a few suggest otherwise.
Spectra indicating abundant enstatite at higher temperatures also require
crystalline silicates at temperatures lower than those required for spectra
showing high abundance of other crystalline silicates. A few spectra show 10
micron complexes of very small equivalent width. They are fit well using
abundant crystalline silicates but very few large grains, inconsistent with the
expectation that low peak-to-continuum ratio of the 10 micron complex always
indicates grain growth. Most spectra in our sample are fit well without using
the opacities of large crystalline silicate grains. If large grains grow by
agglomeration of submicron grains of all dust types, the amorphous silicate
components of these aggregates must typically be more abundant than the
crystalline silicate components. Crystalline silicate abundances correlate
positively with other such abundances, suggesting that crystalline silicates
are processed directly from amorphous silicates and that neither forsterite,
enstatite, nor silica are intermediate steps when producing either of the other
two. Disks with more dust settling typically have greater crystalline
abundances. Large-grain abundance is somewhat correlated with greater settling
of disks. The lack of strong correlation is interpreted to mean that settling
of large grains is sensitive to individual disk properties. Lower-mass stars
have higher abundances of large grains in their inner regions. | Source: | arXiv, 0811.3622 | Services: | Forum | Review | PDF | Favorites |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
| News, job offers and information for researchers and scientists:
| |