High-resolution study of the young stellar objects in Mon R2 IRS 3
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
Corresponding author: T. Preibisch, preib@mpifr-bonn.mpg.de
Received:
22
May
2002
Accepted:
21
June
2002
We present a bispectrum speckle interferometry study of the embedded
young stellar objects in Mon R2 IRS 3 in the near-infrared
H and K bands. Our images with a resolution of
75 mas (
AU) show a close triple system surrounded by
strong diffuse nebulosity and three additional infrared sources
(K magnitudes ~11.8–13.7)
within 
of the brightest object IRS 3 A (
).
We use HST/NICMOS archive images to derive near-infrared photometry for the
sources and estimate the stellar masses of the three brightest objects
IRS 3 A, B, and C to be in the range ~5–
.
IRS 3 A is surrounded by a bipolar nebula (position angle ~
),
suggesting
it to be embedded in a thick circumstellar disk or a torus with polar cavities.
IRS 3 B shows a remarkable jet-like emission feature pointing
towards the north-east (position angle 
). This feature consists
of at least three individual knots with projected separations of
130, 230, and 290 mas (110, 190, and 240 AU) from IRS 3 B,
which are much brighter in the K band than
in the H band. This strongly indicates outflow activity from IRS 3 B, which
is therefore probably the source of the compact high velocity molecular outflow
reported from Mon R2 IRS 3.
We also analyze Chandra X-ray archive data for the Mon R2 region and find
IRS 3 A and IRS 3 C to be sources of hard (
keV) and variable
X-ray emission, suggesting plasma temperatures of at least 
K.
The similarity of the X-ray properties to those of Class I protostars
suggests magnetic interaction between the protostars and their circumstellar
disks to be the origin of the X-ray emission; this provides indirect evidence
for the presence of circumstellar disks in the
intermediate- to high-mass young stellar objects IRS 3 A and IRS 3 C.
Key words: techniques: interferometric / stars: individual: Mon R2 IRS 3 / stars: formation / stars: X-rays / stars: winds, outflows
© ESO, 2002