A Wide-Field Near-Ir H2 2.122$\mu$m line survey of the Braid Nebula Star Formation Region in Cygnus OB7

TL;DR

This study uses wide-field near-infrared H2 line observations to identify and analyze outflows and their sources in the Braid Nebula region, revealing new outflows, protostars, and star formation patterns.

Contribution

It provides the first comprehensive near-infrared survey of outflows in the Braid Nebula, uncovering new features and linking outflow activity to protostellar evolution and star formation progression.

Findings

Identified 37 new MHOs and 28 outflows in the region.

Discovered at least 18 protostars, mostly younger or more energetic than in Taurus-Auriga.

Suggested a connection between outflow ejection and FU Ori outbursts.

Abstract

Context. Outflows and jets are the first signposts of ongoing star formation processes in any molecular cloud, yet their study in optical bands provides limited results due to the large extinction present. Near-infrared unbiased wide-field observations in the H2 1-0 S(1) line at 2.122{\mu}m alleviates the problem, enabling us to detect more outflows and trace them closer to their driving sources. Aims. As part of a large-scale multi-waveband study of ongoing star formation in the Braid Nebula Star Formation region, we focus on a one square degree region that includes Lynds Dark Nebula 1003 and 1004. Our goal is to find all of the near-infrared outflows, uncover their driving sources and estimate their evolutionary phase. Methods. We use near-infrared wide-field observations obtained with WFCAM on UKIRT, in conjunction with previously-published optical and archival MM data, to search for outflows and identify their driving sources; we subsequently use colour-colour analysis to determine the evolutionary phase of each source. Results. Within a one square degree field we have identified 37 complex MHOs, most of which are new. After combining our findings with other wide-field, multi-waveband observations of the same region we were able to discern 28 outflows and at least 18 protostars. Our analysis suggests that these protostars are younger and/or more energetic than those of the Taurus-Auriga region. The outflow data enable us to suggest connection between outflow ejection and repetitive FU Ori outburst events. We also find that star formation progresses from W to E across the investigated region.