Spectroscopic, photometric, and polarimetric study of the Herbig Ae candidate HD 36112

Citation
Ng. Beskrovnaya et al., Spectroscopic, photometric, and polarimetric study of the Herbig Ae candidate HD 36112, ASTRON ASTR, 343(1), 1999, pp. 163-174
Citations number
37
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY AND ASTROPHYSICS
ISSN journal
00046361 → ACNP
Volume
343
Issue
1
Year of publication
1999
Pages
163 - 174
Database
ISI
SICI code
0004-6361(199903)343:1<163:SPAPSO>2.0.ZU;2-T
Abstract
We describe observations of the Herbig Ae candidate HD 36112 including high -resolution spectroscopy of photospheric and circumstellar lines, multi-col our photometry and polarimetry. These observations reveal that many feature s of the observational appearance of HD 36112 are similar to those of 'clas sical' Herbig Ae stars. Among these are: the far IR excess, manifestations of the high-temperature zone in the inner envelope, distinctive types of th e H alpha profile variations, and variable multi-component polarization and brightness parameters. The fundamental characteristics of the star have been determined. In partic ular, HD 36112 proves to be an unreddened A8 v of age t similar to 5 divide d by 10 x 10(6) years. This means, that the star is still at the PMS phase of evolution, but close to the ZAMS. The anomalous abundances of barium and silicon discovered in HD 36112 allow to suggest that chemical anomalies ca n arise already at the early stages of stellar evolution. The totality of observed properties of HD 36112 give evidence of complicate d structure of the gaseous-dusty envelope around this object, including the variable stellar wind with an extended acceleration zone, as well as large and small-grained dust, located in the orthogonal planes.