Basic HTML Version
117
Reaching for the Stars
SARChI Chairs
associated with this theme
Multi-wavelength
Astronomy at UCT
Professor Claude Carignan currently holds the South
African Square Kilometre Array (SKA) Research Chair
in Multi-wavelength Astronomy in the Department of
Astronomy. Recruited from the University of Montreal
(Canada) in 2011, he is also an Emeritus Professor at
the Laboratoire d’Astrophysique Expérimentale of the
Département de physique of the Université de Montréal,
and Associate Professor in the Laboratoire de Physique
et Chimie de l’Environnement and in the Observatoire
d’Astrophysique de l’Université de Ouagadougou, both
in Burkina Faso. He has also been very involved in the
development of astronomy in Burkina Faso and in the
setting up of the African Astronomical Society (AfAS) in
that country.
Professor Carignan is an expert on galaxy dynamics
and dark matter and specialises in the study of the
mass distribution in galaxies, using both radio synthesis
and optical Fabry-Perot interferometric techniques. His
primary contribution to research in Astrophysics has
been the study of the mass distribution in late-type spiral
and dwarf galaxies, carried out in the last twenty-five
years. His research in this area has demonstrated that
the contribution of dark matter to the total mass of dwarf
galaxies (
∼
90%) is much more important than in massive
spirals (
∼
50%). Moreover, contrary to the situation in
spirals where dark matter contributes mainly in the outer
parts, dark matter in dwarfs contributes at all radii. This is
demonstrated for the galaxy DDO 154, now a prototype
of its class. Most of this work was done using radio HI
kinematical data.
Astrophysics and Space
Science
Professor Thomas Jarrett has held the DST/NRF South
African Research Chair in Astrophysics and Space
Science in the Department of Astronomy since mid-
2012. Professor Jarrett is an internationally renowned
researcher who was based for more than 20 years in the
United States as a mission scientist at the Jet Propulsion
Laboratory of the California Institute of Technology,
specialising in star-formation and extragalactic studies
using space-borne instrumentation.
Leading or co-leading over 125 peer-reviewed articles
in high-impact journals, his research efforts have focused
on key elements of extragalactic science. Travelling to
locations spanning the globe, he employs in his fieldwork
ground-based, airborne and space-based observatories
and remote-sensing instrumentation to gather data
for analysis of the physical processes that govern the
cosmos. His expertise with infrared astronomy spans the
entire window: from the near-infrared (1 to 3 microns)
that is used to study the stellar mass of galaxies, to the
mid-infrared (4 to 50 microns) that is sensitive to star-
formation and interstellar medium processes, and the
far-infrared (50 to 500 microns) which traces the coldest
and most massive gas and dust content of galaxies. His
most recent article that highlights this research, entitled
A Cosmic Perspective, Multi-wavelength Astrophysics
,
will be published in the Spring issue of the South African
Quest
magazine.
In anticipation of the SKA Era, Professor Jarrett’s research
has also exploited the unique capabilities of the radio
window to study continuum (3, 6 and 20 cm) and 21 cm
hydrogen lineemissionbygalaxies. Combining information
from a plethora of multi-wavelength instrumentation, he
will explore the interconnection between the gas reservoir,
as traced by HI (atomic hydrogen) observations, and the
tracers of past-to-present galaxy evolution as measured
using ultraviolet, visual, infrared and sub-millimetre
observations. In conjunction with these themes, Professor
Jarrett is a founding or key member of a number of large-
science teams, including Spitzer (the fourth and final of
the NASA Great Observatories programmes) and WISE
(NASA’s Wide-field Infrared Survey Explorer), and is an
active science-team member of a number of studies,
including the SKA-Pathfinder studies and MeerKAT key-
science projects.
Professor Jarrett currently supervises threepostdoctoral
research fellows, one PhD student and two MSc students.
He is currently actively involved in the development of a
long-term strategy plan for astronomy in South Africa.
Professor Claude Carignan
Professor Thomas Jarrett