The Spitzer c2d Survey of Nearby Dense Cores: VI. The Protostars of Lynds Dark Nebula 1221

TL;DR

This study uses Spitzer and radio observations to identify and analyze three protostars in Lynds Dark Nebula 1221, revealing differences in their properties and environments, and providing insights into early star formation processes.

Contribution

First infrared and radio observations of protostars in L1221, with detailed dust modeling showing distinct protostar characteristics in similar environments.

Findings

Identification of three protostars, two newly known.

Detection of outflow signatures supporting protostar activity.

Different luminosities and envelope sizes suggest varying evolutionary stages.

Abstract

Observations of Lynds Dark Nebula 1221 from the Spitzer Space Telescope are presented. These data show three candidate protostars towards L1221, only two of which were previously known. The infrared observations also show signatures of outflowing material, an interpretation which is also supported by radio observations with the Very Large Array. In addition, molecular line maps from the Five College Radio Astronomy Observatory are shown. One-dimensional dust continuum modelling of two of these protostars, IRS1 and IRS3, is described. These models show two distinctly different protostars forming in very similar environments. IRS1 shows a higher luminosity and larger inner radius of the envelope than IRS3. The disparity could be caused by a difference in age or mass, orientation of outflow cavities, or the impact of a binary in the IRS1 core.