Summary: Astronomy & Astrophysics manuscript no.
(will be inserted by hand later)
Bispectrum speckle interferometry of the massive protostellar
object S140 IRS 1: evidence for multiple outflows ?
Gerd Weigelt 1 , Yuri Y. Balega 2 , Thomas Preibisch 1 , Dieter Schertl 1 , Michael D. Smith 3
1 Max­Planck­Institut f¨ur Radioastronomie, Auf dem H¨ugel 69, D--53121 Bonn, Germany
2 Special Astrophysical Observatory, Nizhnij Arkhyz, Zelenchuk region, Karachai­Cherkesia, 357147, Russia
3 Armagh Observatory, College Hill, Armagh BT61 9DG, Northern Ireland
the date of receipt and acceptance should be inserted later
Abstract. Bispectrum speckle interferometry is employed to explore the immediate environment of the deeply
embedded young stellar object S140 IRS 1. A K 0 ­band (2:0 \Gamma 2:3 ¯m) diffraction­limited resolution of 76 mas
(¸ 70 AU) is achieved with the SAO 6 m telescope, as well as a dynamical range of more than 8 magnitudes
and a field of view of 13 00 \Theta 21 00 . 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 south­east, which was
already discussed in a previous paper (Schertl et al. 2000), we find several arc­like structures north­east of IRS 1,
extended diffuse emission south of IRS 1, and four new point sources. The diffuse and fragmentary structures close
to IRS1 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 00 and 100 00 . A system of three arc­like structures
to the north­east is consistent with cavities excavated by a precessing jet or wind­driven outflow. We discuss the

Source: Armagh Observatory

Collections: Physics