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Related papers: The SiC problem: astronomical and meteoritic evide…

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Interplanetary dust (IPD) scatters solar radiation which results in the zodiacal light that dominates the celestial diffuse brightness at optical and near-infrared wavelengths. Both asteroid collisions and cometary ejections produce the…

As part of a reanalysis of galactic Asymptotic Giant Branch (AGB) stars at infrared (IR) wavelengths, we discuss a sample (357) of carbon stars for which mass loss rates, near-IR photometry and distance estimates exist. For 252 sources we…

Astrophysics · Physics 2016-08-30 R. Guandalini , M. Busso , S. Ciprini , G. Silvestro , P. Persi

It is becoming clear that determination of the abundance of Si using lines of Si II and Si III can lead to quite discordant results in mid to late B-type stars. The difference between the Si abundances derived from the two ion states can…

Solar and Stellar Astrophysics · Physics 2015-06-12 Jeffrey D. Bailey , John D. Landstreet

% context {Nano-diamonds are an enticing and enigmatic dust component yet their origin is still unclear. They have been unequivocally detected in only a few astronomical objects, yet they are the most abundant of the pre-solar grains, both…

Astrophysics of Galaxies · Physics 2022-01-26 A. P. Jones , Nathalie Ysard

We decompose the COBE/DIRBE observations of the near-IR sky brightness (minus zodiacal light) into Galactic stellar and interstellar medium (ISM) components and an extragalactic background. This empirical procedure allows us to estimate the…

Astrophysics · Physics 2009-11-07 Richard G. Arendt , Eli Dwek

New, high-resolution MARCS synthetic spectra have been calculated for more than a dozen mixtures of the metals allowing, in turn, for variations in C:N:O, [CNO/Fe], and enhanced abundances of C, O, Mg, and Si. Bolometric Corrections (BCs)…

Solar and Stellar Astrophysics · Physics 2021-12-15 Don A. VandenBerg , Bengt Edvardsson , Luca Casagrande , Jason W. Ferguson

Dwarf carbon (dC) stars, main sequence stars showing carbon molecular bands, were initially thought to be an oxymoron since only AGB stars dredge carbon into their atmospheres. Mass transfer from a former AGB companion that has since faded…

Silicate carbon stars show the 10 micron silicate emission, despite their carbon-rich photospheres. They are considered to have circumbinary or circum-companion disks, which serve as a reservoir of oxygen-rich material shed by mass loss in…

Foreground emission and scattered light from interplanetary dust (IPD) particles and emission from Galactic stellar sources are the greatest obstacles for determining the cosmic infrared background (CIB) from diffuse sky measurements in the…

Astrophysics · Physics 2009-09-28 E. Dwek , R. G. Arendt

Graphite is one of the many presolar circumstellar condensate species found in primitive meteorites. While the isotopic compositions of low-density graphite grains indicate an origin in core-collapse supernovae, some high-density grains…

Earth and Planetary Astrophysics · Physics 2015-06-17 Manavi Jadhav , Marco Pignatari , Falk Herwig , Ernst Zinner , Roberto Gallino , Gary R. Huss

Carbon-rich grains with isotopic anomalies compared to the Sun are found in primitive meteorites. They were made by stars, and carry the original stellar nucleosynthesis signature. Silicon carbide grains of Type X and C, and low-density…

Solar and Stellar Astrophysics · Physics 2015-08-06 M. Pignatari , E. Zinner , P. Hoppe , C. J. Jordan , B. K. Gibson , R. Trappitsch , F. Herwig , C. Fryer , R. Hirschi , F. X. Timmes

While the upcoming telescopes will reveal correspondingly fainter, more distant galaxies, a question will persist: what more is there that these telescopes cannot see? One answer is the source-subtracted Cosmic Infrared Background (CIB).…

We investigate the IR spectral features of a sample of D-type symbiotic stars. Analyzing unexploited ISO-SWS data, deriving the basic observational parameters of dust bands and comparing them with respect to those observed in other…

Astrophysics · Physics 2008-11-26 R. Angeloni , M. Contini , S. Ciroi , P. Rafanelli

Aliphatic hydrocarbons exhibit an absorption feature at 3.4 micron observed toward sources that sample diffuse regions of the interstellar medium. The absorbers responsible for this feature are assumed to reside in some component of…

The cosmic infrared background (CIB) radiation was a long-sought fossil of energetic processes associated with structure formation and chemical evolution since the Big Bang. The COBE Diffuse Infrared Background Experiment (DIRBE) and Far…

Astrophysics · Physics 2007-05-23 M. G. Hauser

Diamond silicon (Si) is the leading material in current solar cell market. However, diamond Si is an indirect band gap semiconductor with a large energy difference (2.4 eV) between the direct gap and the indirect gap, which makes it an…

Materials Science · Physics 2013-03-18 H. J. Xiang , Bing Huang , Erjun Kan , Su-Huai Wei , X. G. Gong

The abundance of both amorphous and crystalline silicates in very small grains is limited by the fact that the 10 micron silicate emission feature is not detected in the diffuse ISM. On the basis of the observed IR emission spectrum for the…

Astrophysics · Physics 2009-10-31 Aigen Li , B. T. Draine

Amorphous silicate dust is a major component in the interstellar and circumstellar dust formed in the outflow of asymptotic giant branch (AGB) stars. Although iron depletion is observed in the interstellar medium (ISM), the exact form and…

Astrophysics of Galaxies · Physics 2026-01-14 Hanako Enomoto , Aki Takigawa , Hiroki Chihara , Chiyoe Koike

The transparency of silicon in the infrared region enables the design of nano/microstructures for implementation in devices to harvest the infrared (IR) part of the solar spectrum. Herein we report a strategy that uses arrays of inverted…

Since thin-film silicon solar cells have limited optical absorption, we explore the effect of a nanostructured back reflector to recycle the unabsorbed light. As a back reflector we investigate a 3D photonic band gap crystal made from…

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