Title :

Low-temperature optical constants of amorphous silicate dust analogues

Author(s) :

Demyk, K. [Auteur]
Institut de recherche en astrophysique et planétologie [IRAP]
Gromov, V. [Auteur]
Space Research Institute of the Russian Academy of Sciences [IKI]
Meny, C. [Auteur]
Institut de recherche en astrophysique et planétologie [IRAP]
Ysard, N. [Auteur]
Institut d'astrophysique spatiale [IAS]
Paradis, D. [Auteur]
Institut de recherche en astrophysique et planétologie [IRAP]
Jones, A. P. [Auteur]
Institut d'astrophysique spatiale [IAS]
Petitprez, Denis [Auteur]
Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 [PC2A]
Hubert, Patrice [Auteur]
Physicochimie des Processus de Combustion et de l’Atmosphère - UMR 8522 [PC2A]
Leroux, Hugues [Auteur]
Unité Matériaux et Transformations - UMR 8207 [UMET]
Nayral, C. [Auteur]
Laboratoire de physique et chimie des nano-objets [LPCNO]
Delpech, F. [Auteur]
Laboratoire de physique et chimie des nano-objets [LPCNO]

Journal title :

Astronomy & Astrophysics

Abbreviated title :

A&A

Volume number :

666

Publisher :

EDP Sciences

Publication date :

2022-10

English keyword(s) :

astrochemistry
methods : laboratory
solid state
techniques
spectroscopic
dust
extinction
infrared
ISM

HAL domain(s) :

Chimie/Matériaux
Physique [physics]/Matière Condensée [cond-mat]/Science des matériaux [cond-mat.mtrl-sci]
Physique [physics]/Physique [physics]/Géophysique [physics.geo-ph]
Physique [physics]/Astrophysique [astro-ph]
Planète et Univers [physics]/Astrophysique [astro-ph]
Planète et Univers [physics]/Sciences de la Terre

English abstract : [en]

Context. Cosmic dust models are key ingredients in advancing our understanding of astronomical environments as diverse as interstellar clouds in galaxies, circumstellar envelopes around evolved and young stars, and ...
Show more >Context. Cosmic dust models are key ingredients in advancing our understanding of astronomical environments as diverse as interstellar clouds in galaxies, circumstellar envelopes around evolved and young stars, and protoplanetary disks. Such models consist of several dust populations, each with different compositions and size distributions. They may also consider different grain shapes, although most models assume spherical grains. All include a component of silicate dust. The absorption and emission properties of these dust components are calculated from the optical constants of each dust material which have various experimental, phenomenological, and theoretical origins depending on the model. Aims. We aim to provide the community with new sets of optical constants for amorphous silicate dust analogues at low temperatures. The analogues consist of four Mg-rich silicate samples of stoichiometry ranging from enstatite to olivine, and of eight samples of Mg- and Fe-rich silicates with a pyroxene stoichiometry and differing magnesium and iron content. Methods. We calculated the optical constants from transmission measurements using the Kramers-Kronig relations, assuming that the grains are small compared to the wavelength and prolate in shape with axis ratios of 1.5 and 2 for the Mg- and Fe-rich samples, respectively. Results. New optical constants for silicate dust analogues of various compositions were calculated over the wavelength range from 5 to 800 µm or 1000 µm, depending on the sample, and at temperatures of 10, 30, 100, 200, and 300 K. We determined the uncertainties on the derived optical constants based on the assumptions used to calculate them. To facilitate the use of these data in cosmic dust models, we provide optical constants extrapolated outside the measured spectral range into the ultraviolet(UV)/visual(VIS)/near-infrared(NIR) and millimetre and centimetre wavelength ranges, as well as formulae that can be used to interpolate the optical constants at any temperature in the range 10–300 K.Show less >

Language :

Anglais

Peer reviewed article :

Oui

Audience :

Internationale

Popular science :

Non

Administrative institution(s) :

Université de Lille
CNRS
INRAE
ENSCL

Collections :

• Physicochimie des Processus de Combustion et de l'Atmosphère (PC2A) - UMR 8522
• Unité Matériaux et Transformations (UMET) - UMR 8207

Research team(s) :

Matériaux Terrestres et Planétaires

Submission date :

2023-06-21T15:46:59Z
2023-06-23T06:36:03Z