HR 4049: an old low-mass star disguised as a young massive supergiant.
The spectroscopic features and the possible nature of the HR 4049, the fifth-magnitude star classified as B9.5-Ib II, are examined. Coudespectra in the 3622-3900 A range, obtained at ESO's 1.52-m telescope, did display Balmer lines (from H9 to the Balmer limit), on the appearance of which the classification as a B9.5 Ib II was based, but no trace of Mg II, Fe II, or Cr II lines, i.e., lines that tend to be prominent in early-A supergiants. The difference between HR 4049 and normal early supergiants was still more prominent in the UV, with no features in common with spectra of typical late-B or early-A-supergiants seen in the HR 4049. It is concluded that, unlike normal supergiants, the HR 4049 is not a massive star. The possible nature of the HR 4049 as a post-asymptotic giant branch star is discussed.
- Pub Date:
- September 1987
- Stellar Color;
- Stellar Evolution;
- Stellar Spectra;
- Supergiant Stars;
- Asymptotic Giant Branch Stars;
- Cosmic Dust;
- Light Curve;
- Spectral Energy Distribution;
- Low-Mass Stars:Energy Distribution;
- Low-Mass Stars:Light Variations;
- Low-Mass Stars:Spectra;
- Spectra:Low-Mass Stars