Submillimeter Research: Figures
Observations of the Eta Carina Complex obtained
with the Antarctic Submillimeter Telescope and Remote Observatory
(AST/RO) located at the South Pole.
The AST/RO telescope studies the interaction between structures
in the Galaxy and the processes in interstellar gas which
give rise to star formation.
Surrounding the unusual young star Eta Carina is
a region where the perturbing effect of a
spiral arm is laid out across the line of sight.
Here the tangent point of the Carina spiral arm
was observed in submillimeter-wave transitions of
carbon monoxide (CO J = 4 to 3, contour units 5 K km/s)
and atomic carbon ([CI]
color scale units K km/s) with AST/RO in 1998.
The spectra have been integrated over a velocity range -50 km/s
to -9 km/s to show total line brightness.
The [CI] and CO lines show the effects of cloud
assembly, heating, and disruption as a function of spiral arm phase.
The spiral density wave shock associated with the Carina arm crossing
may be playing an important role in the formation and dissociation
of the cloud complex, as well as in maintaining the internal energy
balance of the clouds. Massive stars form at the densest regions of
the molecular cloud complex. The winds and outflows associated
with these stars have a disrupting effect on the complex
and inject mechanical energy into the parent clouds, while massive
young stars heat the parent clouds with UV radiation.
The AST/RO data suggest, however, that massive stars alone
may not account for the energetics of the clouds in the Carina region or
their chemistry. The details of the data and the
correlation among the various data sets hint at
the possible role that the spiral density wave
plays in feeding interstellar turbulence.
This research is published by Zhang et al. 1999.
South Pole Imaging Fabry-Perot Interferometer
(SPIFI) mounted on
the right Nasmyth focus of the James Clark Maxwell Telescope (JCMT)
near the 4200 m summit of Mauna Kea, HI, during a successful
A schematic showing the mounting of SPIFI on the
CARA AST/RO telescope. SPIFI was installed on AST/RO to
test the mount in January 1999 although no astronomical observation
were made at that time. Astronomical testing was made on
the JCMT telescope. With the success of the
JCMT observations, SPIFI is on schedule to be deployed on the AST/RO telescope
in December 2000.
CARA winter-over scientists receive training on how to operate the
Submillimeter Polarimeter for Antarctic Remote Observations (SPARO),
the first sub-Kelvin detector system designed for use at the South
Pole during the Antarctic winter. From left to right: winter-over
Greg Griffin, Northwestern graduate student David Chuss, and
winter-over John Davis. Greg Griffin is turning a knob on SPARO which
is mounted to the Viper telescope. SPARO observations will reveal the
configuration of the magnetic field within our Galaxy's nucleus.