Light scattering studies of randomly oriented polycrystalline fayalite micro particles as interstellar dust analogues

Boruah, Manash J.; Gogoi, Ankur; Nath, Bikash Chandra; Ahmed, Gazi A.

doi:10.1016/j.jqsrt.2017.04.019

Cited by 6 publications

(6 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The resolution of the angular measurements is set at 5°, for each of the characterizations. More details of the setup are described elsewhere [46]. Accuracy of the measurements has been ensured by subtracting the background intensity, i.e., the signals without the scatterer.…”

Section: Methodsmentioning

confidence: 99%

“…The particle surfaces are slightly deformed by displacing the volumetric meshes (provided in the software), to simulate the particle surface roughness and irregularities. The target generation processes are described in detail in our previous publications [45,46]. These representative models of the realistic particle samples are then converted to arrays of dipoles using another software package, DDSCAT Convert©, using 2 × 10 5 dipoles for each of the modeled geometries.…”

Section: • Comparison Of the Theoretical Values Of Computed Scat-mentioning

confidence: 99%

“…These representative models of the realistic particle samples are then converted to arrays of dipoles using another software package, DDSCAT Convert©, using 2 × 10 5 dipoles for each of the modeled geometries. In each of the cases the distance between two adjacent dipoles is fixed at 0.1 Å, then using a total dipole volume model to populate the target geometries with the desired number of dipole distributions [46]. Results of the conversion are saved as shape.dat files, which are directly exported into the DDSCAT Fortran code.…”

Section: • Comparison Of the Theoretical Values Of Computed Scat-mentioning

confidence: 99%

“…The averaging over shapes and sizes is done using an indigenously developed MATLAB post-processing tool which utilizes volumetric ensemble averaging [46].…”

Section: Size Distributionmentioning

confidence: 99%

See 3 more Smart Citations

Visible light scattering properties of irregularly shaped silica microparticles using laser based laboratory simulations for remote sensing and medical applications

Boruah¹,

Ahmed²

2017

Laser Phys.

View full text Add to dashboard Cite

Laser based experimental light scattering studies of irregularly shaped silica microparticles have been performed at three incident wavelengths 543.5 nm, 594.5 nm and 632.8 nm supported by laboratory based computations and 3D realistic simulations, using an indigenously fabricated light scattering setup. A comparative analysis of the computational and experimentally acquired results is done and a good agreement is found in the forward scattering lobes in all cases for each of the measured scattering parameters. This study also provides an efficient way of detecting and measuring particle size distribution for irregular micro-and nanoparticles and is highly applicable in remote sensing, atmospheric, astrophysical, and medical applications and also for finding potential health hazards in the form of inhalable and respirable small particulate matter.

show abstract

Section: Methodsmentioning

confidence: 99%

Section: • Comparison Of the Theoretical Values Of Computed Scat-mentioning

confidence: 99%

Section: • Comparison Of the Theoretical Values Of Computed Scat-mentioning

confidence: 99%

“…The averaging over shapes and sizes is done using an indigenously developed MATLAB post-processing tool which utilizes volumetric ensemble averaging [46].…”

Section: Size Distributionmentioning

confidence: 99%

See 2 more Smart Citations

Visible light scattering properties of irregularly shaped silica microparticles using laser based laboratory simulations for remote sensing and medical applications

Boruah¹,

Ahmed²

2017

Laser Phys.

View full text Add to dashboard Cite

show abstract

“…In our experiment, we used olivine made up of 80% of forsterite and 20% of fayalite. Fayalite (Fe 2 Si0 4 ), the iron end-member of the olivine group, was found in the interstellar medium and meteorite (Boruah et al 2017). Also forsterite Mg 2 SiO 4 , the magnesium-rich end-member of the olivine group, was found in different astrophysical environments from meteorites (Weinbruch et al 2000) to protoplanetary disk (Fujiyoshi et al 2015).…”

Section: Choice Of Molecules and Olivine Mineralmentioning

confidence: 99%

Thermal desorption of astrophysical relevant ice mixtures of acetaldehyde and acetonitrile from olivine dust

Corazzi,

Brucato,

Poggiali

et al. 2021

Preprint

View full text Add to dashboard Cite

Millimeter and centimeter observations are discovering an increasing number of interstellar complex organic molecules (iCOMs) in a large variety of star forming sites, from the earliest stages of star formation to protoplanetary disks and in comets. In this context it is pivotal to understand how the solid phase interactions between iCOMs and grain surfaces influence the thermal desorption process and, therefore, the presence of molecular species in the gas phase. In laboratory, it is possible to simulate the thermal desorption process deriving important parameters such as the desorption temperatures and energies. We report new laboratory results on temperature-programmed desorption (TPD) from olivine dust of astrophysical relevant ice mixtures of water, acetonitrile, and acetaldehyde. We found that in the presence of grains, only a fraction of acetaldehyde and acetonitrile desorbs at about 100 K and 120 K respectively, while 40% of the molecules are retained by fluffy grains of the order of 100 µm up to temperatures of 190 -210 K. In contrast with the typical assumption that all molecules are desorbed in regions with temperatures higher than 100 K, this result implies that about 40% of the molecules can survive on the grains enabling the delivery of volatiles towards regions with temperatures as high as 200 K and shifting inwards the position of the snowlines in protoplanetary disks. These studies offer a necessary support to interpret observational

show abstract

Scattering by interstellar graphite and fayalite composite dust analogues: computer simulation and laser-based laboratory measurements

2021

View full text Add to dashboard Cite

Light scattering studies of randomly oriented polycrystalline fayalite micro particles as interstellar dust analogues

Cited by 6 publications

References 42 publications

Visible light scattering properties of irregularly shaped silica microparticles using laser based laboratory simulations for remote sensing and medical applications

Visible light scattering properties of irregularly shaped silica microparticles using laser based laboratory simulations for remote sensing and medical applications

Thermal desorption of astrophysical relevant ice mixtures of acetaldehyde and acetonitrile from olivine dust

Scattering by interstellar graphite and fayalite composite dust analogues: computer simulation and laser-based laboratory measurements

Contact Info

Product

Resources

About