NEW HERBIG-HARO OBJECTS AND PRE-MAIN-SEQUENCE STARS IN THE STAR FORMATION REGION NGC-7129

Citation
Lf. Miranda et al., NEW HERBIG-HARO OBJECTS AND PRE-MAIN-SEQUENCE STARS IN THE STAR FORMATION REGION NGC-7129, Astronomy and astrophysics, 271(2), 1993, pp. 564-573
Citations number
26
Categorie Soggetti
Astronomy & Astrophysics
Journal title
ISSN journal
00046361
Volume
271
Issue
2
Year of publication
1993
Pages
564 - 573
Database
ISI
SICI code
0004-6361(1993)271:2<564:NHOAPS>2.0.ZU;2-3
Abstract
We present CCD images of the central part of the star forming region N GC 7129 as well as spectra of moderate spectral and high spatial resol ution of some nebular objects and stars. The images show many reflecti on filaments which seem to trace the edges of the molecular cavity ass ociated with the pre-main-sequence star LkHalpha234. Three new T Tauri -like stars and five new Herbig-Haro (HH) objects have been identified in the region. One of the new young stars probably illuminates an elo ngated reflection filament. One of the HH objects presents a highly co llimated structure and an abrupt and unusually large bending of almost -equal-to 90-degrees. The object emanates from the Halpha-emission lin e star HL 14. Our spectra indicate that this star is likely to be a T Tauri-like star. Large and systematic variations of the radial velocit y, electron density, excitation degree and velocity dispersion exist i n the object. The data favor the idea that the object is a jet-like ou tflow which encounters an obstacle - density enhancement or pressure g radient - in the cloud and deflects. The obstacle could be related to the walls of the molecular cavity associated with LkHalpha234 or to th e energetic wind from this star.