Open AccessSiC 2 in carbon stars: Merrill–Sanford absorption bands between 4100 and 5500 Å
Author(s) -
Sarre P. J.,
Hurst M. E.,
Lloyd Evans T.
Publication year - 2000
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2000.03818.x
Subject(s) - physics , carbon star , stars , astrophysics , photosphere , spectral line , absorption (acoustics) , giant star , absorption spectroscopy , atomic physics , astronomy , optics
Observations and identifications of the Merrill–Sanford bands of the silicon dicarbide molecule are reported for a range of N and J stars. The data were recorded at 0.8−1.6 Å resolution between 4100 and 5500 Å. A full description of the assignments and spectral features in the stars is given. The spectra are characterized by absorption from the ground vibrational level (0, 0, 0) and from higher‐lying vibrational levels involving one quantum of excitation in ν 1 , and up to two quanta in ν 2 and ν 3 , giving rise to numerous hot‐bands. The first results of rotational contour calculations are presented, and are consistent with SiC 2 lying in the upper atmosphere of the star with a rotational temperature substantially lower than that of the photosphere.