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Description
Main-sequence (MS) and giant late-B and early-A type stars are the best targets for searching for nearby interstellar (IS) SiIV and CIV resonance lines because they are not able to produce them, either in atmospheric layers or in their circumstellar environment, and because many stars of these spectral types are nearby and located in the local interstellar medium (LISM). In addition, the use of certain stars hotter than B6 can lead to misinterpretations (e.g., alpha Arae). This work analyzes the reliable Short-Wavelength Prime (SWP) high-resolution UV spectra of 558 B6-A9 type stars observed by the International Ultraviolet Explorer at distances lower than 400pc from the Sun. For the first time, this work utilizes the entire INES database to extract stellar and IS information in a systematic way from homogeneous data. Stars were classified into seven groups: normal (MS and subgiant), giant, peculiar, emission line, Algols, pre-main sequence or Herbig Ae/Be, and shell stars. Only 10 normal stars, located beyond 90pc, show weak SiIV and CIV absorptions and are clustered around the direction of Sco-Cen, while 85 located closer than 90pc, as well as another 89 beyond 90pc, do not show any absorptions at all.
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