Issue |
A&A
Volume 437, Number 1, July I 2005
|
|
---|---|---|
Page(s) | 217 - 226 | |
Section | Stellar structure and evolution | |
DOI | https://doi.org/10.1051/0004-6361:20035824 | |
Published online | 10 June 2005 |
Crowded field 3D spectroscopy of LBV candidates in M 33
1
Special Astrophysical Observatory, Nizhnij Arkhyz, Karachaevo-Cherkesia, 369167, Russia e-mail: fabrika@sao.ru
2
Astrophysikalisches Institut Potsdam, An der Sternwarte 16, 14482, Potsdam, Germany e-mail: mmroth@aip.de
Received:
9
December
2003
Accepted:
22
February
2005
We present integral field spectroscopy of the LBV
candidate stars B 416 and v 532 in the local group galaxy M 33.
B 416 is surrounded by an elongated ring-like nebula, which has
a projected radius of pc.
From the datacube we create ionization and radial velocity maps of
the nebula. The excitation of the gas decreases towards the outer part
of the ring, while the inner part of the nebula is filled with a more excited
gas. In the EW direction the ring is seen to expand with a maximum
projected velocity amplitude of about 40 km s-1. The eastern
part approaches the observer. We estimate the nebula dynamical lifetime
∼
years. It could be a residual MS bubble,
which indicates a main-sequence or pre-LBV status of the star.
We classify B 416 as an “iron star” or B[e]-supergiant.
In v 532 an elongated nebula has been marginally detected.
The total projected size of the nebula along the main axis is 30 pc,
and the total radial velocity gradient is
km s-1.
v 532 exhibits both strong photometric and spectral variability.
At the time of our observations it was in an intermediate
brightness state with a rich nitrogen spectrum.
We classify v 532 as an LBV, showing LBV
Ofpe/WN
transitions.
We stress the importance of
integral field spectroscopy as the optimal technique for studying nebulae
and the evolution of LBV-like stars in nearby galaxies.
Key words: Local Group / stars: early-type / stars: individual: v 532 / HII regions / stars: individual: B416 / galaxies: individual: M 33
© ESO, 2005
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.