Figure 3.
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.
hosts’ thick disks, rather than dissipate. The
studied z ~ 0.1 galaxies were selected from
among a larger sample identified by large
Hα luminosity, which then further showed
smooth rotation of their disks. These cases
are additionally similar to the high-z examples in stellar mass and in high luminosity of
the detected gas clumps (Figure 3).
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.
July 2014
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.
Nancy A. Levenson is Deputy Director and Head
of Science at Gemini Observatory and can be
reached at: [email protected]
GeminiFocus
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