Figure 10.
amples in stellar mass
and in high luminosity of the detected gas
clumps (Figure 10).
The observations were
made using the Gemini Mulit-Object Spectrograph Integral Field
Units on both Gemini
telescopes. Stellar absorption lines and ionized gas emission lines
provide kinematic measurements of the stellar and gas components of the galaxies. Both
the gas and the stars show smooth rotation
and large velocity dispersion.
The kinematic similarity of these components suggests a common external origin for
turbulence that results in the large velocity
dispersion, as opposed to a feedback mechanism whereby stellar processes (including
winds and supernovae) act on the gas alone.
A preprint is now available and publication
is forthcoming in Monthly Notices of the Royal Astronomical Society.
B[e] supergiants deposit enriched material
in the interstellar medium through mass
loss (during post-main-sequence phases)
and ultimately as supernovae. The mass loss
can result in disks and rings, and the progenitor of  Supernova 1987A in the Large
Magellanic Cloud may, in fact, be a B[e]
supergiant. Besides increasing the known
population of these rare objects, M31 offers an interesting host environment, having higher metallicity (about twice solar)
compared with previous examples.
False-color images
of the galaxies
constructed from the
Gemini IFU data, with
continuum, Hb, and
[O III] in red, green,
and blue, respectively.
The circles show the
continuum peaks,
which are coincident
with the kinematic
center in each case. The
arrows mark locations
of clumps, which
are evident as local
emission-line peaks.
Figure 11.
GNIRS continuumsubtracted spectra of
two newly identified
B[e] supergiants in
M31 (black), exhibiting
the hydrogen Pfund
series and both 12CO
and 13CO. The red lines
represent model fits to
the observations.
April 2014
Discovery of the First B[e]
Supergiants in M31
Michaela Kraus (Akademie ved Ceske republiky, Czech Republic) and collaborators
from Argentina and Brazil have used the
Gemini Near-Infrared Spectrograph (GNIRS)
on Gemini North to identify the first B[e] supergiants in the nearby galaxy M31. These
stars represent a short-lived phase of evolution of massive stars, after their time on the
main sequence.
These stars are broadly relevant first in the
context of stellar evoluti