Oral Presentation

Assessing the Reliability of the Polarization–Intensity Gradient Method in Realistic Star-Forming Environments

Author(s): Jo-Shui Kao (NTHU/ASIAA), Shih-Ping Lai (NTHU), Hsi-Wei Yen (ASIAA), Patrick Koch (ASIAA)

Presenter: Kao Jo-shui (NTHU/ASIAA)

Magnetic fields play a crucial role in the process of star formation and the evolution of collapsing dense cores. However, direct measurements of magnetic field strength from observations remain challenging. The polarization–intensity gradient method is a new approach to estimate the magnetic field strength using polarization angle and intensity gradient, which can provide the map of position-dependent magnetic field strength estimates. In this project, we evaluate the applicability and robustness of this method when applied to realistic observational conditions. We perform synthetic James Clerk Maxwell Telescope (JCMT) observations based on simulations of the Orion molecular cloud (Ntormousi & Hennebelle 2019), and apply the polarization–intensity gradient method to estimate the magnetic field strength. We then compare the derived field strengths with the intrinsic values from the simulation to quantify the associated uncertainties. Furthermore, we discuss the physical conditions and environments of dense cores under which the polarization–intensity gradient method provides reliable estimates. Our results aim to clarify the limitations and applicability of this method in interpreting observations of star-forming regions.