Volume 415, Number 1, February III 2004
|Page(s)||179 - 187|
|Section||Interstellar and circumstellar matter|
|Published online||03 February 2004|
Sub-arcsecond imaging and spectroscopic observations of the Red Rectangle in the N-band
Kiso Observatory, Institute of Astronomy, School of Science, University of Tokyo, Kiso, Nagano, Japan e-mail: email@example.com
2 Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Sagamihara, Kanagawa, Japan
3 Institute of Physics, Center for Natural Science, Kitasato University, Sagamihara, Kanagawa, Japan
4 Department of Astronomy, School of Science, University of Tokyo, Hongo, Tokyo, Japan
5 Subaru Telescope, National Astronomical Observatory of Japan, Hilo, USA
Corresponding author: T. Miyata, firstname.lastname@example.org
Accepted: 13 October 2003
We carried out imaging and long-slit spectroscopic observations of the Red Rectangle in the N-band using the 8.2-m SUBARU telescope. The resulting images reveal a central bright core and an extended nebula. The central core is slightly extended in the N-band. The core radius is estimated to be ~, which corresponds to 60 AU. The core spectrum is well modeled by blackbody emission with a temperature of 358 K. The estimated size and temperature are in good agreement with the predictions of recent dusty torus models. In the north/south nebula, unidentified infrared (UIR) emission features at 8.6 μm and 11.2 μm are prominently observed. At radii > they completely dominate the N-band spectra, suggesting that the nebula seen at N-band wavelengths is primarily brightened by the UIR-band emission, not by scattered light. We also detected shifts in the UIR-feature peaks with increasing distance from the center. These may be attributed to isotopic shifts due to the presence of in polycyclic aromatic hydrocarbons (PAH) like particles. In addition to the UIR emission, a broad feature at 11.27 μm is seen at a distance of 0.3´´ on all sides of the nebula. We attribute this to crystalline silicate olivine grains around the central torus.
Key words: circumstellar matter / stars: individual: Red Rectangle / stars: AGB and post-AGB / infrared: stars
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.