Pure rotational spectra of TiO and TiO2 in VY Canis Majoris

  title={Pure rotational spectra of TiO and TiO2 in VY Canis Majoris},
  author={Tomasz Kamiński and Carl A. Gottlieb and Karl M. Menten and Nimesh Patel and K. H. Young and Sandra Brunken and Holger S. P. Muller and Michael C. McCarthy and Jack M. Winters and Leen Decin},
  journal={Astronomy and Astrophysics},
We report the first detection of pure rotational transitions of TiO and TiO2 at (sub-)millimeter wavelengths towards the red supergiant VY CMa. A rotational temperature, Trot, of about 250 K was derived for TiO2. Although Trot was not well constrained for TiO, it is likely somewhat higher than that of TiO2. The detection of the Ti oxides confirms that they are formed in the circumstellar envelopes of cool oxygen-rich stars and may be the “seeds” of inorganic-dust formation, but alternative… 

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