On Magnesium Sulfide as the Carrier of the 30micron Emission Feature in Evolved Stars (2009)
Zhang, Ke, Jiang, Biwei, Li, Aigen
A large number of carbon-rich evolved objects (asymptotic giant branch stars, protoplanetary nebulae, and planetary nebulae) in both the Milky Way galaxy and the Magellanic Clouds exhibit an...
The 21 micron and 30 micron circumstellar dust features in evolved C-rich objects (2008)
Jiang, B. W., Zhang, Ke, Li, Aigen
The 21micron and 30micron bands are the strongest dust emission features detected in evolved low- and intermediate-mass C-rich stars (i.e. asymptotic giant branch [AGB] stars, proto-planetary nebulae...
Gao, Jian, Jiang, B. W., Li, Aigen
Observationally, both the 3.4micron aliphatic hydrocarbon C--H stretching absorption feature and the 9.7micron amorphous silicate Si--O stretching absorption feature show considerable variations from...
Probing Cosmic Dust of the Early Universe through High-Redshift Gamma-Ray Bursts (2008)
We explore the extinction properties of the dust in the distant universe through the afterglows of high-redshifted GRBs based on the "Drude" model which, unlike previous studies, does not require a...
Complex Organic Materials in the HR 4796A Disk? (2008)
Koehler, M., Mann, I., Li, Aigen
The red spectral shape of the visible to near infrared reflectance spectrum of the sharply-edged ring-like disk around the young main sequence star HR 4796A was recently interpreted as the presence...
On Dust Extinction of Gamma-ray Burst Host Galaxies (2008)
Li, Aigen, Liang, S. L., Kann, D. A., Wei, D. M., Klose, S., Wang, Y. J.
Although it is well recognized that gamma-ray burst (GRB) afterglows are obscured and reddened by dust in their host galaxies, the wavelength-dependence and quantity of dust extinction are still...
Dust in Active Galactic Nuclei (2008)
Dust plays an essential role in the unification theory of active galactic nuclei (AGNs). This review summarizes our current understanding of the extinction and infrared emission properties of the...
Li, M. P., Shi, Q. J., Li, Aigen
The recent Spitzer detections of the 9.7 micron Si--O silicate emission in type 1 AGNs provide support for the AGN unification scheme. The properties of the silicate dust are of key importance to...
Optical Properties of Dust (2008)
Except in a few cases cosmic dust can be studied in situ or in terrestrial laboratories, essentially all of our information concerning the nature of cosmic dust depends upon its interaction with...
On Buckyonions as an Interstellar Grain Component (2008)
Li, Aigen, Chen, J. H., Li, M. P., Shi, Q. J., Wang, Y. J.
The carrier of the 2175 Angstrom interstellar extinction feature remains unidentified since its first detection over 40 years ago. In recent years carbon buckyonions have been proposed as a carrier...
On the Crystallinity of Silicate Dust in the Interstellar Medium (2008)
Li, M. P., Zhao, G., Li, Aigen
An accurate knowledge of the mineralogy (chemical composition and crystal structure) of the silicate dust in the interstellar medium (ISM) is crucial for understanding its origin in evolved stars,...
PAHs in Comets: An Overview (2008)
Polycyclic aromatic hydrocarbon (PAH) molecules, ubiquitously seen in the interstellar medium (ISM) of our own and external galaxies, might have been incorporated into comets if they are formed from...
Li, Yuan, Li, Aigen, Wei, Daming
The dust extinction of gamma-ray bursts (GRBs) host galaxies, containing important clues to the nature of GRB progenitors and crucial for dereddening, is still poorly known. Here we propose a...
A Comet Dust Model for the (2007)
Pictoris Disk Aigen, Aigen Li, J. Mayo Greenberg
. The 10 m silicate emission feature and the continuum emission from near infrared to millimeter of the dust in the disk of fi Pictoris may be derived by assuming that the dust is continually...
Dust and Atomic Gas in Dwarf Irregular Galaxies of the M81 Group: The SINGS and THINGS View (2007)
Walter, Fabian, Cannon, John M., Roussel, Hélène, Bendo, George J., Calzetti, Daniela, Dale, Daniel A., ...
We present observations of the dust and atomic gas phase in seven dwarf irregular galaxies of the M81 group from the Spitzer SINGS and VLA THINGS surveys. The Spitzer observations provide a first...
Bolatto, Alberto D., Simon, Joshua D., Stanimirović, Snežana, Van Loon, Jacco Th., Shah, Ronak Y., Venn, Kim, ...
We present the initial results from the Spitzer Survey of the Small Magellanic Cloud (S^3MC), which imaged the star-forming body of the SMC in all seven MIPS and IRAC wave bands. We find that the...
Dust and atomic gas in dwarf irregular galaxies of the M81 group: the SINGS and THINGS view (2007)
Walter, Fabian, Cannon, John M., Roussel, Hélène, Bendo, George J., Calzetti, Daniela, Dale, Daniel A., ...
We present observations of the dust and atomic gas phase in seven dwarf irregular galaxies of the M81 group from the Spitzer SINGS and VLA THINGS surveys. The Spitzer observations provide a first...
Bolatto, Alberto D., Simon, Joshua D., Stanimirovic, Snezana, Van Loon, Jacco Th., Shah, Ronak Y., Venn, Kim, ...
We present the initial results from the Spitzer Survey of the Small Magellanic Cloud (S3MC), which imaged the star-forming body of the Small Magellanic Cloud (SMC) in all seven MIPS and IRAC...
Bendo, George J., Dale, Daniel A., Draine, Bruce T., Engelbracht, Charles W., Kennicutt, Robert C., ...
We explore the nature of variations in dust emission within an individual galaxy using 3.6 - 160 micron Spitzer Space Telescope observations and 450 and 850 micron James Clerk Maxwell Telescope...
Infrared (IR) emission spectra are calculated for dust composed of mixtures of amorphous silicate and graphitic grains, including varying amounts of polycyclic aromatic hydrocarbon (PAH) particles....
Warm Dust and Spatially Variable PAH Emission in the Dwarf Starburst Galaxy NGC 1705 (2006)
Cannon, John M., Smith, John-David T., Walter, Fabian, Bendo, George J., Calzetti, Daniela, Dale, Daniel A., ...
We present Spitzer observations of the dwarf starburst galaxy NGC 1705 obtained as part of SINGS. The galaxy morphology is very different shortward and longward of ~5 microns: short-wavelength...
Biller, Beth A., Close, Laird M., Li, Aigen, Marengo, Massimo, Bieging, John H., Hinz, Phil M., ...
We imaged the symbiotic star CH Cyg and two PSF calibration stars using the unique 6.5m MMT deformable secondary adaptive optics system. Our high-resolution (FWHM=0.3"), very high Strehl (98%+-2%)...
Li, Aigen, Misselt, K. A., Wang, Y. J.
The dust in the Small Magellanic Cloud (SMC), an ideal analog of primordial galaxies at high redshifts, differs markedly from that in the Milky Way by exhibiting a steeply rising far-ultraviolet...
Dust Extinction of Gamma-ray Burst Host Galaxies: Identification of Two Classes? (2006)
Chen, Shilun, Li, Aigen, Wei, Daming
Dust in the host galaxies of gamma-ray bursts (GRBs) dims and reddens their afterglow spectra. Knowledge of the nature of this dust is crucial for correcting for extinction, providing clues to the...
Cannon, John M., Smith, John-David T., Walter, Fabian, Bendo, George J., Calzetti, Daniela, Dale, Daniel A., ...
We present Spitzer observations of the nearby dwarf starburst galaxy NGC 1705 obtained as part of the Spitzer Infrared Nearby Galaxies Survey. The galaxy morphology is very different shortward and...
Jiang, B. W., Zhang, Ke, Li, Aigen
The mysterious 21mu emission feature seen in 12 proto-planetary nebulae (PPNe) remains unidentified since its first detection in 1989. Over a dozen of candidate materials have been proposed within...
Can Fluffy Dust Alleviate the "Subsolar" Interstellar Abundance Problem? (2005)
What might be the most appropriate set of interstellar reference abundances of chemical elements (both in gas and in dust) relative to hydrogen has been a subject of much discussion in the past...
On the Absorption and Emission Properties of Interstellar Grains (2005)
Our current understanding of the absorption and emission properties of interstellar grains are reviewed. The constraints placed by the Kramers-Kronig relation on the wavelength-dependence and the...
Interstellar Grains -- The 75th Anniversary (2005)
The year of 2005 marks the 75th anniversary since Trumpler (1930) provided the first definitive proof of interstellar grains by demonstrating the existence of general absorption and reddening of...
The Warm, Cold and Very Cold Dusty Universe (2005)
We are living in a dusty universe: dust is ubiquitously seen in a wide variety of astrophysical environments, ranging from circumstellar envelopes around cool red giants to supernova ejecta, from...
Phase Functions and Light Curves of Wide Separation Extrasolar Giant Planets (2005)
Sudarsky, David, Burrows, Adam, Hubeny, Ivan, Li, Aigen
We calculate self-consistent extrasolar giant planet (EGP) phase functions and light curves for orbital distances ranging from 0.2 AU to 15 AU. We explore the dependence on wavelength, cloud...
Detections of the 2175 \AA Dust Feature at 1.4z 1.5 from the Sloan Digital Sky Survey (2004)
Wang, Junfeng, Hall, Patrick B., Ge, Jian, Li, Aigen, Schneider, Donald P.
The strongest spectroscopic dust extinction feature in the Milky Way, the broad absorption bump at 2175 \AA, is generally believed to be caused by aromatic carbonaceous materials -- very likely a...
Modeling the Infrared Emission from the HD 141569A Disk (2003)
We model the infrared (IR) emission from the double-ring disk of HD 141569A, using a porous dust model that was previously shown successful in reproducing the spectral energy distributions (SEDs) of...
Modeling the Infrared Emission from the HR 4796A Disk (2003)
We model the spectral energy distribution (SED) from the mid-infrared to submillimeter of the ring-like disk of HR 4796A, the dustiest A-type star. We consider dust made either of coagulated but...
Interaction of Nanoparticles with Radiation (2003)
Interstellar grains span a wide range of sizes from a few angstroms to a few micrometers. The presence of nanometer-sized or smaller particles in the interstellar medium is indicated directly by the...
Titanium carbide (TiC) nanocrystals were recently proposed as the carrier of the mysterious 21$\mum$ emission feature observed in post-asymptotic giant branch stars, based on their close spectral...
Modeling the Infrared Emission from the Epsilon Eridani Disk (2003)
Li, Aigen, Lunine, J. I., Bendo, G. J.
We model the infrared (IR) emission from the ring-like dust disk around the main-sequence (MS) star Epsilon Eridani, a young analog to our solar system, in terms of a porous dust model previously...
A Search for Sodium Absorption from Comets Around HD209458 (2003)
Mendelowitz, Caylin, Ge, Jian, Mandell, Avi M., Li, Aigen
We monitored the planet-bearing solar-type star HD209458 for sodium absorption in the region of the stellar NaI D1 line that would be indicative of cometary activity in the system. We observed the...
Cosmic Needles versus Cosmic Microwave Background Radiation (2002)
It has been suggested by a number of authors that the 2.7K cosmic microwave background (CMB) radiation might have arisen from the radiation from Population III objects thermalized by conducting...
What Can We Learn from the Infrared Spectral Energy Distributions of Dust Disks? (2002)
The spectral energy distributions (SEDs) of dust disks are widely used to infer dust properties (compositions and sizes) and disk structures (dust spatial distributions) which might be indicative of...
In Dust We Trust: An Overview of Observations and Theories of Interstellar Dust (2002)
The past century of interstellar dust has brought us from first ignoring it to finding that it is an important component of the interstellar medium and plays an important role in the evolution of...
Mid-Infrared Spectropolarimetric Constraints on the Core-Mantle Interstellar Dust Model (2002)
In the framework of the silicate core-carbonaceous organic mantle interstellar dust model, the bulk of the visual/near-IR extinction and the entire polarization are from nonspherical and aligned...
Modelling the Astronomical Silicate Features: I. On the Spectrum Subtraction Method (2002)
Li, Aigen, Greenberg, J. Mayo, Zhao, Gang
The {\it assumption of additive absorptivity} by different components in compound particles is a widely used method applied in the literature to the analysis of the chemical and structural properties...
One of the major challenges to identification of the 3.3, 6.2, 7.7, 8.6, and 11.3um interstellar IR emission bands with polycyclic aromatic hydrocarbon (PAH) molecules has been the recent detection...
Infrared Emission from Interstellar Dust. III. The Small Magellanic Cloud (2001)
The infrared (IR) emission from interstellar dust in the Small Magellanic Cloud (SMC) is modelled using a mixture of amorphous silicate and carbonaceous grains, including a population of polycyclic...
Are Silicon Nanoparticles an Interstellar Dust Component? (2000)
Silicon nanoparticles (SNPs) have been proposed as the source of the observed "extended red emission" (ERE) from interstellar dust. We calculate the thermal emission expected from such particles in a...
On Ultrasmall Silicate Grains in the Diffuse Interstellar Medium (2000)
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...
Infrared Emission from Interstellar Dust. I. Stochastic Heating of Small Grains (2000)
We present a method for calculating the infrared emission from a population of dust grains heated by starlight, including very small grains for which stochastic heating by starlight photons results...
Infrared Emission from Interstellar Dust. II. The Diffuse Interstellar Medium (2000)
We present a quantitative model for the infrared emission from dust in the diffuse interstellar medium. The model consists of a mixture of amorphous silicate grains and carbonaceous grains, each with...