The Launch Region of the SVS 13 Outflow and Jet
Abstract
We present the results of Keck telescope laser adaptive-optics integral field spectroscopy with OSIRIS of the innermost regions of the NGC 1333 SVS 13 outflow that forms the system of Herbig-Haro objects 7-11. We find a bright 0.''2 long microjet traced by the emission of shock-excited [Fe II]. Beyond the extent of this jet, we find a series of bubbles and fragments of bubbles that are traced in the lower excitation H2 1-0 S(1) line. While the most recent outflow activity is directed almost precisely (P.A. ≈ 145°) to the southeast of SVS 13, there is clear indication that prior bubble ejections were pointed in different directions. Within these variations, a clear connection between the newly observed bubble ejection events and the well-known, poorly collimated HH 7-11 system of Herbig-Haro objects is established. The astrometry of the youngest of the expanding shock fronts at three epochs, covering a timespan of over 2 yr, gives kinematic ages for two of these bubbles. The kinematic age of the youngest bubble is slightly older than the historically observed last photometric outburst of SVS 13 in 1990, consistent with that event, launching the bubble and some deceleration of its expansion. A re-evaluation of historic infrared photometry and new data show that SVS 13 has not yet returned to its brightness before that outburst and thus reveal behavior similar to FUor outbursts, albeit with a smaller amplitude. We postulate that the creation of a series of bubbles and the changes in outflow direction are indicative of a precessing disk and accretion events triggered by a repetitive phenomenon possibly linked to the orbit of a close binary companion. However, our high-resolution images in the H and K bands do not directly detect any companion object. We have tried, but failed, to detect the kinematic rotation signature of the microjet in the [Fe II] emission line at 1.644 μm.
- Publication:
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The Astrophysical Journal
- Pub Date:
- October 2014
- DOI:
- 10.1088/0004-637X/794/2/169
- arXiv:
- arXiv:1408.5940
- Bibcode:
- 2014ApJ...794..169H
- Keywords:
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- Herbig-Haro objects;
- infrared: stars;
- ISM: jets and outflows;
- stars: formation;
- stars: individual: SVS 13;
- stars: variables: T Tauri;
- Herbig Ae/Be;
- Astrophysics - Solar and Stellar Astrophysics
- E-Print:
- This paper has been accepted for publication in The Astrophysical Journal