Astron. Astrophys. Suppl. Ser.
Volume 120, Number 1, November II 1996
|Page(s)||157 - 177|
|Published online||15 November 1996|
The Pictoris phenomenon among Herbig Ae/Be stars. UV and optical high dispersion spectra *
Eureka Scientific, 2452 Delmer Street, Suite 100, Oakland CA 94602, U.S.A.
2 Applied Research Corp., Suite 1120, 8201 Corporate Dr., Landover, MD 20785, U.S.A.
3 Laboratorio de Astrofisica Espacial y Fisica Fundamental, I.N.T.A., Apartado 50727, 28080- Madrid, Spain
4 Space Astronomy Laboratory, University of Wisconsin, Madison WI 53706-1390, U.S.A.
5 Astronomical Institute “Anton Pannekoek”, University of Amsterdam, Kruislaan 403, 1098 SJ Amsterdam, The Netherlands
6 Department of Physics, University of Cincinnati, Cincinnati OH 45221-0011, U.S.A.
7 Ritter Observatory and Department of Physics and Astronomy, University of Toledo, Toledo OH 43606, U.S.A.
8 Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, U.S.A.
9 CSC-IUE Observatory, GSFC, Greenbelt, MD 20771, U.S.A.
10 Department of Physics, East Tennessee State University, Box 70652, Johnson City TN 37614, U.S.A.
Corresponding author: Send offprint request to: C.A. Grady, e-mail: email@example.com
Accepted: 10 April 1996
We present a survey of high dispersion UV and optical spectra of Herbig Ae/Be (HAeBe) and related stars. We find accreting, circumstellar gas over the velocity range +100 to +400 km s-1, and absorption profiles similar to those seen toward β Pic, in 36% of the 33 HAeBe stars with IUE data as well as in 3 non-emission B stars. We also find evidence of accretion in 7 HAeBe stars with optical data only. Line profile variability appears ubiquitous. As a group, the stars with accreting gas signatures have higher than the stars with outflowing material, and tend to exhibit large amplitude () optical light variations. All of the program stars with polarimetric variations that are anti-correlated with the optical light, previously interpreted as the signature of a dust disk viewed close to equator-on, also show spectral signatures of accreting gas. These data imply that accretion activity in HAeBe stars is preferentially observed when the line of sight transits the circumstellar dust disk. Our data imply that the spectroscopic signatures of accreting circumstellar material seen in β Pic are not unique to that object, but instead are consistent with interpretation of β Pic as a comparatively young A star with its associated circumstellar disk.
Key words: stars: β Pic: pre-main sequence / circumstellar matter / line: profiles / ultraviolet: stars
Based on observations made with the International Ultraviolet Explorer operated by NASA and ESA, and at the European Southern Observatory, La Silla, Chile, the Cerro Tololo Inter-American Observatory of the National Optical Astronomy Observatories, and the Ritter Observatory of the University of Toledo
© European Southern Observatory (ESO), 1996