Polarimetry of DG Tau at 350 microns

TL;DR

This study reports the first 350 micron polarization measurement of DG Tau's disk, providing empirical constraints that challenge existing models and suggesting multiwavelength polarimetry as a tool for probing disk opacity.

Contribution

First 350 micron polarization measurement of DG Tau's disk, offering new empirical data that challenge current models and propose multiwavelength polarimetry for disk opacity studies.

Findings

No polarization detected at 350 microns.

Discrepancy between observed polarization spectrum and recent model predictions.

Adding mass to the disk model could reconcile predictions with observations.

Abstract

We present the first 350 micron polarization measurement for the disk of the T Tauri star (TTS) DG Tau. The data were obtained using the SHARP polarimeter at the Caltech Submillimeter Observatory. We did not detect polarization but we provide constraints on the normalized Stokes parameters q and u. We derive information about the polarization spectrum by comparing our 350 micron result with an 850 micron polarization detection previously published for this source. This empirical information concerning the polarization spectrum disagrees with the predictions of a recent model for TTS disk polarization. We conclude, however, that adding more mass to the model disk would probably result in model polarization spectra that agree much better with the 350 and 850 micron polarimetric observations. We suggest that multiwavelength polarimetry of TTS disk emission may provide a promising method for probing the opacity of TTS disks.