Umana, G. and Buemi, C. S. and Trigilio, C. and Leto, P. and Agliozzo, C. and Ingallinera, A. and Noriega-Crespo, A. and Hora, J. L. (2011) Expanded Very Large Array Observations of the Nebula Around G79.29+0.46. Astrophysical Journal Letters, 739 (1). Art. No. L11 . ISSN 0004-637X http://resolver.caltech.edu/CaltechAUTHORS:20110926-111538537
- Published Version
See Usage Policy.
Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20110926-111538537
We have observed the radio nebula surrounding the Galactic luminous blue variable candidate G79.29+0.46 with the Expanded Very Large Array (EVLA) at 6 cm. These new radio observations allow a morphological comparison between the radio emission, which traces the ionized gas component, and the mid-IR emission, a tracer of the dust component. The InfraRed Array Camera (8 μm) and the Multiband Imaging Photometer for Spitzer (24 μm and 70 μm) images have been reprocessed and compared with the EVLA map. We confirm the presence of a second shell at 24 μm and also provide evidence for its detection at 70 μm. The differences between the spatial morphology of the radio and mid-IR maps indicate the existence of two dust populations, the cooler one emitting mostly at longer wavelengths. Analysis of the two dusty, nested shells have provided us with an estimate of the characteristic timescales for shell ejection, providing important constraints for stellar evolutionary models. Finer details of the ionized gas distribution can be appreciated thanks to the improved quality of the new 6 cm image, most notably the highly structured texture of the nebula. Evidence of interaction between the nebula and the surrounding interstellar medium can be seen in the radio map, including brighter features that delineate regions where the shell structure is locally modified. In particular, the brighter filaments in the southwest region appear to frame the shocked southwestern clump reported from CO observations.
|Additional Information:||© 2011 The American Astronomical Society. Received 2011 April 14; accepted 2011 June 9; published 2011 August 29. This work is based in part on observations made with the Spitzer Space Telescope, which is operated by the Jet Propulsion Laboratory, California Institute of Technology under a contract with NASA. Support for this work was provided by NASA through an award issued by JPL/Caltech.|
|Subject Keywords:||circumstellar matter; infrared: stars; stars: early-type; stars: individual (G79.29+0.46); stars: winds, outflows|
|Classification Code:||PACS: 96.10.+i; 97.10.Cv; 98.70.Lt; 97.20.Ec; 97.10.Me; 97.10.Fy|
|Official Citation:||Expanded Very Large Array Observations of the Nebula Around G79.29+0.46 G. Umana et al. 2011 ApJ 739 L11|
|Usage Policy:||No commercial reproduction, distribution, display or performance rights in this work are provided.|
|Deposited By:||Ruth Sustaita|
|Deposited On:||26 Sep 2011 18:31|
|Last Modified:||26 Dec 2012 13:42|
Repository Staff Only: item control page