First proper motions of thin dust filaments at the Galactic center
Abstract
Context: L'-band (3.8 μm) images of the Galactic center show a large number of thin filaments in the mini-spiral, located west of the mini-cavity and along the inner edge of the Northern Arm. One possible mechanism that could produce such structures is the interaction of a central wind with the mini-spiral. Additionally, we identify similar features that appear to be associated with stars.
Aims: We present the first proper motion measurements of the thin dust filaments observed in the central parsec around SgrA* and investigate possible mechanisms that could be responsible for the observed motions.
Methods: The observations have been carried out using the NACO adaptive optics system at the ESO VLT. The images have been transformed to a common coordinate system and features of interest were extracted. Then a cross-correlation technique could be performed in order to determine the offsets between the features with respect to their position in the reference epoch.
Results: We derive the proper motions of a number of filaments and 2 cometary shaped dusty sources close (in projection) to SgrA*. We show that the shape and the motion of the filaments does not agree with a purely Keplerian motion of the gas in the potential of the supermassive black hole at the position of SgrA*. Therefore, additional mechanisms must be responsible for their formation and motion. We argue that the properties of the filaments are probably related to an outflow from the disk of young mass-losing stars around SgrA*. In part, the outflow may originate from the black hole itself. We also present some evidence and theoretical considerations that the outflow may be collimated.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 2007
- DOI:
- 10.1051/0004-6361:20066265
- arXiv:
- arXiv:0704.3675
- Bibcode:
- 2007A&A...469..993M
- Keywords:
-
- Galaxy: center;
- infrared: ISM;
- ISM: jets and outflows;
- accretion;
- accretion disks;
- Astrophysics
- E-Print:
- accepted for publication by A&