The circumstellar structure of the Be shell star Per *
I. Data analysis
S. tefl 1,
W. Hummel 2 and
Th. Rivinius 3,4
Received 19 February 2000 / Accepted 14 March 2000
We present new phase resolved observations of emission lines of the Be binary Per.
Analyzing the orbital phase variations in the HeI emission features we find strong arguments that the feature as a whole originates in the outer parts of the disk around the primary star. In addition to the HeI 6678 and 5876 lines, the emission features with orbital phase variations were detected in three more HeI lines. The observations are in agreement with the scenario of Poeckert and others, in which the outer parts of an axisymmetric disk are illuminated by the radiation of the secondary. The observations after 1996 are consistent with a growing global density inhomogeneity in the circumprimary disk as it occurs in disks of single Be stars. The combination of the illumination effect and the increasing density inhomogeneity make Per an ideal laboratory to study density perturbations of circumstellar disks of Be stars in more detail.
Key words: line: profiles radiative transfer stars: binaries: general stars: circumstellar matter stars: emission-line, Be stars: individual: OE Per
* Based on observations collected at the Ondejov Observatory (of the Academy of Sciences of the Czech Republic), Heidelberg Observatory, German-Spanish Astronomical Center (DSAZ) - Calar Alto (operated by the Max-Plank-Institut für Astronomie Heidelberg jointly with the Spanish National Commission for Astronomy) and Observatoire de Haute-Provence (OHP; CNRS, France)
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© European Southern Observatory (ESO) 2000
Online publication: June 26, 2000