view Abstract Citations (2) References Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A Comparative Study of the Spectra of a BOÖTIS and 70 Ophiuchi a. van Dijke, Suzanne E. A. Abstract The weaker lines in the photographic region of the spectra of a Boötis and 70 Ophiuchi A have been compared visually and photometrically on high-dispersion coudé plates. A résumé of the behavior of the elements in the two stars is given. The relative weakness of the X 3883 band of CN and several multiplets of Ca I in the giant and the relative strength of Laii and the singly ionized rare earths are especially noted. Curves of growth for the neutral iron lines have been constructed for both stars. The observed veloc- ity and damping factor for a Boötis are 3.25 km/sec and 0.8 X 1O~, respectively. The solar values were assumed for the dwarf. Relative abundances are obtained, and departure from equilibrium is evident for the giant. The Adams-Russell formula provides a satisfactory correction. Values of the excitation temperatures and of the log of the relative electron pressures are 31600, 41500, and -3.74, -1.10 for the giant and dwarf, re- spectively. The results are compared to the sunspot spectrum, and the suggestion is made of a stratifica- tion of elements in the atmosphere of the giant similar to that found in the sun Publication: The Astrophysical Journal Pub Date: July 1946 DOI: 10.1086/144831 Bibcode: 1946ApJ...104...27V full text sources ADS |