scholarly journals Mapping the Interstellar Dust with Near-Infrared Observations: An Optimized Multi-Band Technique

Author(s):  
Marco Lombardi ◽  
João Alves
1997 ◽  
Vol 163 ◽  
pp. 725-726
Author(s):  
K.-W. Hodapp ◽  
E. F. Ladd

Stars in the earliest phases of their formation, i.e., those accreting the main component of their final mass, are deeply embedded within dense cores of dust and molecular material. Because of the high line-of-sight extinction and the large amount of circumstellar material, stellar emission is reprocessed by dust into long wavelength radiation, typically in the far-infrared and sub-millimeter bands. Consequently, the youngest sources are strong submillimeter continuum sources, and often undetectable as point sources in the near-infrared and optical. The most deeply embedded of these sources have been labelled “Class 0” sources by André, Ward-Thompson, & Barsony (1994), in an extension of the spectral energy distribution classification scheme first proposed by Adams, Lada, & Shu (1987).


2012 ◽  
Vol 5 (2) ◽  
pp. 2933-2957
Author(s):  
C. Prigent ◽  
C. Jiménez ◽  
J. Catherinot

Abstract. Previous studies examined the possibility to estimate the aeolian aerodynamic roughness length from satellites, either from visible/near-infrared observations or from microwave backscattering measurements. Here we compare the potential of the two approaches and propose to merge the two sources of information to benefit from their complementary aspects, i.e. the high spatial resolution of the visible/near-infrared (PARASOL part of the A-Train) and the independence from atmospheric contamination of the active microwaves (ASCAT on board MetOp). A global map of the aeolian aerodynamic roughness length at 6 km resolution is derived, for arid and semi-arid regions. It shows very good consistency with the existing information on the properties of these surfaces. The dataset is available to the community, for use in atmospheric dust transport models.


2011 ◽  
Vol 728 (2) ◽  
pp. 85 ◽  
Author(s):  
M. Janson ◽  
J. Carson ◽  
C. Thalmann ◽  
M. W. McElwain ◽  
M. Goto ◽  
...  
Keyword(s):  

2007 ◽  
Vol 467 (3) ◽  
pp. 1025-1036 ◽  
Author(s):  
M. Gullieuszik ◽  
E. V. Held ◽  
L. Rizzi ◽  
I. Saviane ◽  
Y. Momany ◽  
...  

2018 ◽  
Vol 483 (4) ◽  
pp. 5110-5122 ◽  
Author(s):  
L Kedziora-Chudczer ◽  
G Zhou ◽  
J Bailey ◽  
D D R Bayliss ◽  
C G Tinney ◽  
...  

2017 ◽  
Vol 46 (34) ◽  
pp. 11149-11153 ◽  
Author(s):  
Yanjie Liang ◽  
Feng Liu ◽  
Yafei Chen ◽  
Xianli Wang ◽  
Kangning Sun ◽  
...  

MgGeO3:Pr3+ and CdSiO3:Pr3+ red/near-infrared/short-wave infrared multi-band persistent phosphors exhibit long-lasting (>120 h) afterglow at 625 nm, 900 nm and 1085 nm.


2004 ◽  
Vol 128 (6) ◽  
pp. 2977-2980 ◽  
Author(s):  
Roger Knacke ◽  
Sergio Fajardo-Acosta ◽  
A. T. Tokunaga

2018 ◽  
Vol 612 ◽  
pp. A69 ◽  
Author(s):  
L. Grosset ◽  
D. Rouan ◽  
D. Gratadour ◽  
D. Pelat ◽  
J. Orkisz ◽  
...  

Aims. In this paper we aim to constrain the properties of dust structures in the central first parsecs of active galactic nuclei (AGN). Our goal is to study the required optical depth and composition of different dusty and ionised structures. Methods. We developed a radiative transfer code called Monte Carlo for Active Galactic Nuclei (MontAGN), which is optimised for polarimetric observations in the infrared. With both this code and STOKES, designed to be relevant from the hard X-ray band to near-infrared wavelengths, we investigate the polarisation emerging from a characteristic model of the AGN environment. For this purpose, we compare predictions of our models with previous infrared observations of NGC 1068, and try to reproduce several key polarisation patterns revealed by polarisation mapping. Results. We constrain the required dust structures and their densities. More precisely, we find that the electron density inside the ionisation cone is about 2.0 × 109 m−3. With structures constituted of spherical grains of constant density, we also highlight that the torus should be thicker than 20 in term of K-band optical depth to block direct light from the centre. It should also have a stratification in density: a less dense outer rim with an optical depth at 2.2 μm typically between 0.8 and 4 for observing the double scattering effect previously proposed. Conclusions. We bring constraints on the dust structures in the inner parsecs of an AGN model supposed to describe NGC 1068. When compared to observations, this leads to an optical depth of at least 20 in the Ks band for the torus of NGC 1068, corresponding to τV ≈ 170, which is within the range of current estimation based on observations. In the future, we will improve our study by including non-uniform dust structures and aligned elongated grains to constrain other possible interpretations of the observations.


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