Bibcode
Molaro, P.; Vladilo, G.; Beckman, J. E.
Bibliographical reference
Astronomy and Astrophysics (ISSN 0004-6361), vol. 161, no. 2, June 1986, p. 339-346.
Advertised on:
6
1986
Citations
26
Refereed citations
25
Description
A study of IUE spectra of eight cool G4-K0 giants shows evidence of
interstellar Mg II absorption in all the stars but Delta Dra. Sharp
features are detected in the emission wings of four stars, while only
strong asymmetries of the emission profiles are noted in three cases. In
all the cases studied, the interstellar absorption features fall very
close to the wavelength predicted by Crutcher's relation (1982),
confirming its validity in the solar neighborhood. The eight new lines
of sight explored are consistent with the sun embedded in, and at the
edge of a warm cloud, and an extension of 20-30 pc for this warm cloud
in the direction of Omicron Sgr, and as little as 6 pc in the direction
of Beta Hyi and HD 81101, is suggested. The Mg II absorption features
are shown to strongly affect the chromospheric emission profiles for
cool stars. Future application to Space Telescope observations is
suggested for the present velocity separation technique.