Bispectrum speckle interferometry of the massive protostellar object S140 IRS 1: Evidence for multiple outflows^*

¹ Max-Planck-Institut für Radioastronomie, Auf dem Hügel 69, 53121 Bonn, Germany
² Special Astrophysical Observatory, Nizhnij Arkhyz, Zelenchuk region, Karachai-Cherkesia, 357147, Russia
³ Armagh Observatory, College Hill, Armagh BT61 9DG, Northern Ireland

Corresponding author: G. Weigelt, weigelt@mpifr-bonn.mpg.de

Received: 26 July 2001
Accepted: 18 October 2001

Abstract

Bispectrum speckle interferometry is employed to explore the immediate environment of the deeply embedded young stellar object S140 IRS 1. A K'-band (2.0-2.3m) diffraction-limited resolution of 76 mas (~70 AU) is achieved with the SAO 6 m telescope, as well as a dynamical range of more than 8 mag and a field of view of . Our image exhibits many previously unseen complex structures. In addition to the bright, elongated, and very clumpy feature pointing from the central source to the south-east, which was already discussed in a previous paper (Schertl et al. [CITE]), we find several arc-like structures north-east of IRS 1, extended diffuse emission south of IRS 1, and four new point sources. The diffuse and fragmentary structures close to IRS 1 appear to trace circumstellar material swept up by energetic outflows. In combination with molecular line emission maps from the literature, our image provides direct confirmation that two distinct bipolar outflow systems continue to be driven from IRS 1 on scales between 3´´ and 100´´. A system of three arc-like structures to the north-east is consistent with cavities excavated by a precessing jet or wind-driven outflow. We discuss the implications for the nature of the central source.