Abstract Details

Name: Prithish Halder
Affiliation: Physical Research Laboratory, Ahmedabad
Conference ID: ASI2020_387
Title : Study of physical properties of cosmic dust from light scattering
Authors and Co-Authors : Prithish Halder
Abstract Type : Oral
Abstract Category : Thesis
Abstract : In this thesis the physical properties of cosmic dust aggregates has been studied with the help of light scattering and image reduction techniques. To study the light scattering properties of cosmic dust aggregates a High-Performance Computation facility has been setup in the Dept. of Physics, Assam University, Silchar. Also a java application for the Superposition t-matrix code called JaSTA has been developed in order to calculate the light scattering properties of cosmic dust aggregates with the help of a GUI for quicker and easier completion. JaSTA-2 has been developed to calculate multi-wavelength computations required for the study of light scattering properties. The study of light scattering properties of dust aggregates (0.7μm ≤ R c ≤ 2.0μm) with a wide range of porosity (P = 0.59 to 0.98) has been carried out using the HPC setup built in the Dept. of Physics, AUS. The results indicate that, when the porosity of the aggregates decreases, keeping characteristic radius RC same for all structures, there is an enhancement in the negative polarization branch (NPB) which is accompanied by a substantial increase in the anisotropies present in the material. Also at the exact backscattering region, the anisotropies are found to be linearly correlated with the porosity of the aggregated structure. Finally the polarimetric study of the dark cloud CB26 has been conducted using 1.04 meter observatory at ARIES, Nainital. It has been found that the local magnetic field of the cloud is almost aligned with the Galactic magnetic field. Also the extinction map reveals the presence of an active central core and a second low dense core. The visual extinction of field stars background to CB26 is estimated from 2MASS and Gaia archives using the Near-Infrared Technique.