SCUBA and Spitzer observations of the Taurus molecular cloud - pulling the bull's tail

TL;DR

This study uses SCUBA and Spitzer observations to analyze a filament in the Taurus molecular cloud, revealing its structure and temperature components without needing grain coagulation, and modeling it with radiative transfer techniques.

Contribution

It provides a detailed multi-wavelength analysis of the Taurus filament, introducing a radiative transfer model that fits the data without grain coagulation assumptions.

Findings

The filament appears as a one-sided structure, called 'the bull's tail'.

The filament has a cold core (~8K) and a warmer shoulder (~12K).

Modeling shows a Plummer-like density profile fits the data without grain coagulation.

Abstract

We present continuum data from the Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT), and the Mid-Infrared Photometer for Spitzer (MIPS) on the Spitzer Space Telescope, at submillimetre and infrared wavelengths respectively. We study the Taurus molecular cloud 1 (TMC1), and in particular the region of the Taurus Molecular Ring (TMR). In the continuum data we see no real evidence for a ring, but rather we see one side of it only, appearing as a filament. We name the filament `the bull's tail'. The filament is seen in emission at 850, 450 and 160um, and in absorption at 70um. We compare the data with archive data from the Infra-Red Astronomical Satellite (IRAS) at 12, 25, 60, 100um, in which the filament is also seen in absorption. We find that the emission from the filament consists of two components: a narrow, cold (~8K), central core; and a broader, slightly warmer (~12K), shoulder of emission. We use a radiative transfer code to model the filament's appearance, either in emission or absorption, simultaneously at each of the different wavelengths. Our best fit model uses a Plummer-like density profile and a homogeneous interstellar dust grain population. Unlike previous work on a similar, but different filament in Taurus, we require no grain coagulation to explain our data.