Our group develops computational codes for synthetic modeling of dust emission and polarization based on dust physical models developed by our group and collaborators. We confront the synthetic data with observational data to test dust physics and constrain magnetic fields.
I. DustPOL
DustPOL is a simple code used to model polarization of starlight and thermal dust emission induced by aligned dust grains based on the Radiative Torque Paradigm. The DustPOL code predicts the polarization degree for the optimal situation where the magnetic fields lie in the plane of the sky. The stable version is available here DustPOL
Dust Physics:
- RAT alignment
- RAT disruption
References:
- Lee, HS., Hoang, Thiem, Le Ngan, and Cho, J., 2020, ApJ: Physical Model of Dust Polarization by Radiative Torque Alignment and Disruption and Implications for Grain Internal Structures
- Tram, LN, Hoang, Thiem, et al, 2021, ApJ: Understanding Polarized Dust Emission from rho Ophiuchi A in Light of Grain Alignment and Disruption by Radiative Torques
II. Updated POLARIS
POLARIS
POLArized RadIation Simulator (POLARIS) is the Monte-Carlor radiative transfer code used to model polarized thermal dust emission from aligned dust grains by radiative torques (RAT) for an analytical model or a MHD simulation model of astrophysical objects. The code is developed by Stefan Reissl from Heidelberg University.
Updated POLARIS
Our group has been updating the original POLARIS by including new dust physical effects developed recently. The updated POLARIS is especially important for physical modeling of dust polarization from dense star-forming regions or intense radiatio fields, such as protostellar environments, massive star-forming regions, and dusty tori around active galactic nuclei.
Dust Physics:
- Dust magnetic properties: paramagnetic and superparamagnetic
- Dust mechanical properties: tensile strength and Young modulus
- External Alignmemt by MRAT (magnetically enhanced RAT) Mechanism
- Internal alignment by Barnett and Inelastic Relaxation
- Rotational disruption by RATs (RATD effect)
References:
- Giang, Nguyen Chau, Hoang, Thiem, Kim, JG, Tram, LN., 2023, MNRAS: Physical modelling of dust polarization from magnetically enhanced radiative torque alignment in protostellar cores with POLARIS
- Giang, Nguyen Chau, Hoang, Thiem, 2024, MNRAS: Effects of grain magnetic properties and grain growth on synthetic dust polarization of MHD simulations in protostellar environments
Our updated POLARIS code is currently under development and available upon requests. If you are interested in using this version, please send us an email.