Astron. Astrophys. 334, 585-591 (1998)

The carbon star IRAS 06088+1909 ^*

A. Richichi ¹, B. Stecklum ², T.M. Herbst ³, P.-O. Lagage ⁴ and E. Thamm <sup>5

1</sup> Osservatorio Astrofisico di Arcetri, Largo E. Fermi 5, I-50125 Firenze, Italy
² Thüringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg, Germany
³ Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg, Germany
⁴ CEA, DSM/DAPNIA/Service d'Astrophysique, CE Saclay, F-91191 Gif-sur-Yvette, France
⁵ Astrophysikalisches Institut und Universitäts-Sternwarte, Schillergässchen 2-3, D-07745 Jena, Germany

Received 12 June 1997 / Accepted 16 February 1998

Abstract

We present first-time investigations, by means of several different techniques in the visual and infrared domains, of the source 06088+1909, discovered by the IRAS satellite and classified as a carbon star on the basis of a SiC emission feature. Our interest for this source started with two lunar occultation events, which showed the presence of extended circumstellar emission on the scale of . Follow-up observations by photometry, polarimetry, spectroscopy, speckle interferometry and two more lunar occultations, have revealed many interesting characteristics, and in particular the presence of a flattened shell around the central star. By combining together all available observational evidence, we have been able to infer some of the properties of this shell, such as its shape, size, temperature of the grains, and mechanism of polarization. The object appears as one more example of the complexity existing in the environments of late-type giants and AGB stars, similar to well-known cases such as the Egg Nebula and the Red Rectangle. In the case of IRAS 06088+1909, it has been possible to conduct such a study at an unprecedented level of angular resolution.

Key words: occultations stars: carbon stars: circumstellar matter stars: fundamental parameters infrared:stars

* Based on observations collected at TIRGO (Gornergrat, Switzerland), and at Calar Alto (Spain). TIRGO is operated by CNR-CAISMI Arcetri, Italy. Calar Alto is operated by the German-Spanish Astronomical Center.

Send offprint requests to: A. Richichi
e-mail: arichichi@arcetri.astro.it

SIMBAD Objects

Contents

• 1. Introduction
• 2. Observations and data reduction
• 3. Observational results
  • 3.1. Lunar occultations
  • 3.2. Near-IR spectrum
  • 3.3. Visual and near-IR photometry and polarimetry
  • 3.4. Speckle interferometry
  • 3.5. Thermal IR imaging
• 4. Interpretation and discussion
• 5. Summary and concluding remarks
• Acknowledgements
• References

© European Southern Observatory (ESO) 1998

Online publication: May 15, 1998

helpdesk.link@springer.de