Line identification in the Ca II K spectral region of sharp-lined B-type stars

¹ The Johns Hopkins University, Department of Physics and Astronomy, Bloomberg Center, 3400 N. Charles Street, Baltimore, MD 21218, USA
² Department of Pure and Applied Physics, The Queen's University of Belfast, Belfast, BT7 1NN, Northern Ireland
³ Department of Astronomy, The University of Texas at Austin, Austin, TX 78712-1083, USA

Corresponding author: N. Lehner, nl@pha.jhu.edu

Received: 27 November 2000
Accepted: 16 February 2001

Abstract

Previous Caii K observations of the B-type star HD 83206 have revealed putative high-velocity interstellar clouds (HVCs) at Local Standard of Rest (LSR) velocities of -80 and -110 kms^-1. Similar results were also found for the sightline towards HD 135485. In this article, we show that these absorption lines are in fact due to stellar Sii features. As the Caii K absorption line in B-type stars is often used to assess the presence and distance of HVCs, we also present a very high quality spectrum of HD 83206 in the Caii K region (~ Åor kms^-1), so that in the future confusion between stellar lines and HVC features may be avoided.