Dust spectrum and polarisation at 850 μm in the massive IRDC G035.39-00.33

Abstract

Using JCMT SCUBA-2/POL-2 together with Planck and Herschel data, the study maps the 850 μm polarisation fraction of the dense filamentary cloud G035.39-00.33. Peak column density N(H2) ~ 7×10^22 cm^-2, temperature ~12 K, mass ~4300 M⊙. The polarisation fraction decreases with column density, suggesting loss of grain alignment above ~10^4 cm^-3, with caveats related to magnetic field geometry and filtering.