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Astrophysics and Space Science

, Volume 77, Issue 1, pp 41–58 | Cite as

The spectrum of the Cr star epsilon ursae majoris

  • H. Gökmen Tektunali
Article

Abstract

Fourteen coudé spectrograms (eight with dispersion 12.4 Å mm−1 and six 7 Å mm−1) of the Cr star ∈UMa (Ap) have been studied. The observations were made at the Haute Provence Observatory. The radial velocities of the various ions have been measured. The existence of Balmer progression in radial velocity is doubtful. The variability of some lines is in the opposite sense of K of Caii. Both a rough and a fine analysis have been made. The results of these analyses are compared and found to be in good agreement. The results of the fine analysis indicate a defect of Al, Si and Ca; Sc, Ti, Fe and Sr are normal, Mg and Ni are in slight excess. V, Cr and Mn are in excess by factors of 3, 12, 19; Y, Zr and Ba are in excess by factors of 9, 15, 30. Rare earths are in excess by factors ranging between 100–1000. These results are compared with the majority of the Cr−Eu−Sr stars.

Keywords

Rare Earth Fine Analysis Radial Velocity Slight Excess Opposite Sense 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© D. Reidel Publishing Company 1981

Authors and Affiliations

  • H. Gökmen Tektunali
    • 1
    • 2
  1. 1.Astronomical Department of Istanbul UniversityTurkey
  2. 2.Astronomical Observatory of TriesteItaly

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