My research probes galaxy evolution over a time span of about 11 billion years, and tries to answer questions such as: What did galaxies look like when the Universe was young? How can we best describe galaxies in a quantitative way? How do changes in galactic structure map onto ideas for the underlying physics of galaxy evolution? Technological advances drive my efforts to answer these questions: at the moment I am building a novel telescope array in New Mexico to image very faint structures in nearby galaxies, and I am using Adaptive Optics on large telescopes to study the evolution of galaxy sizes over cosmic time.
I am interested in the study of the birth and evolution of binary stars and planetary systems, dynamics of astrophysical disks, physics of circumstellar dust, with occasional diversions to binary blackholes and AGNs
University Professor, CITAEarly Universe; Origin and Evolution of Cosmic Structure; Cosmic Radiation Backgrounds; The Dark Matter & Dark Energy Problems; Particle and Gravitational Theory.Ph.D. 1979, Caltech
My research is focused on understanding the structure and formation of galaxies, in particular the Milky Way. I use data from large surveys to investigate the distribution of stars in the Milky Way and how this distribution depends on the age and chemical composition of stars, which allows me to identify the basic processes that govern the formation and evolution of the Milky Way and disk galaxies like it. I am also interested in using the observed kinematics of stars to infer the distribution of mass—dark matter in particular—in our Galaxy. I am an active member of the APOGEE survey, which uses high-resolution, high signal-to-noise infrared spectroscopy to investigate the structure of the bulge and disk regions of the Milky Way, as well as many other topics in stellar and galactic astrophysics.
I am primarily interested in cosmology and galaxy formation and evolution using both observational and theoretical approaches. Recently I was one of the leaders of the Supernova Legacy Survey which found that the dark energy was constant in time to a precision of better than 10%, consistent with Einstein’s cosmological constant. I am also interested in star streams as indicators of the dark matter substructure of the Milky Way halo. I has been the Canadian Thirty Meter Telescope Project Director since 2003.
My main goal is to understand why the Universe is magnetic. By measuring the polarised radio signals from millions of distant galaxies over the entire sky, I aim to transform our understanding of magnetism in galaxies, clusters and in diffuse intergalactic gas. I also study the ways in which celestial objects change, flicker, flare and explode. I am working to provide a new understanding of the many different populations of transient and variable phenomena, and to develop the novel source-finding and classification algorithms needed to find rare and unusual behaviour in very large data sets. In the next decade, all of this work will culminate in the Square Kilometre Array, a next-generation radio telescope that will answer fundamental questions about the Universe.
My research focuses on theoretical cosmology and statistical methods in cosmology. I am a member of the Atacama Cosmology Telescope collaboration and the Simons Observatory, which are studying the cosmic microwave background (or CMB) at very sharp angular resolution to unlock the secrets of the early universe and the period of star formation. I use this data to answer questions about the structure of the universe, its initial conditions and its eventual fate using data.
I am also a member of the Dark Energy Science Collaboration of LSST, which is a telescope under construction in Northern Chile, and will scan the sky to deliver a vast amount of cosmic transients. I work on the supernova science with LSST to use the photometric data (without a spectrum of the object) to answer questions about dark energy.
I’m passionate about science communication and outreach, and the intersection of art and science – so contact me if you’re interested in collaboration!
Together with my students and postdoctoral fellows, I use data from telescopes around the world –including the VLT, Subaru, Gemini and CFHT– and in space –such as Kepler and Spitzer– to explore the origins and diversity of planetary systems as well as the formation and evolution of brown dwarfs and stars. Recent efforts have focused on characterizing exoplanet atmospheres, direct imaging and spectroscopy of sub-stellar companions around young stars, searching for the lowest-mass free-floating objects in nearby young clusters, and investigating brown dwarfs at the L/T transition.
I study the physics in stellar atmospheres. The physics is intriguing because the conditions, which cannot be recreated in our labs, are changing extremely rapidly between the dense stellar interior and the near vacuum of space. However, we have the great advantage of being able to observe directly the brightness and spectrum of the stellar atmosphere. A recent revolutionary observational development is the technique of optical/infrared interferometry that resolves the surfaces of the nearer stars. My approach concentrates on the bright stars that can be observed in the greatest detail, and to interpret those observations using computer models
Assistant Professor, UTSCPlanetary interiors: structure, thermal histories, mantle convection, core-mantle coupling; computational fluid dynamics; high performance computing and numerical modellingPh.D. 1996, York University
Professor, CITAInterstellar matter, H2: collisional rate ceofficients, Canadian Galactic Plane Survey, infrared imaging: HiRes, MSX and SIRTF, H II regions: Orion, structure, dynamics and chemical abundances, dust: interstellar polarization.Ph.D. 1972, Cambridge
I study astrophysical fluid dynamics with an emphasis on star formation, stellar feedback in the interstellar medium, accretion, and explosive transients, using analytical studies, numerical simulations, and observations. Recent projects include ways to constrain the interactions between star clusters and galaxies, models for star cluster feedback in starburst galaxies, a catalog of young giant star clusters, long-duration modeling of stellar tidal disruptions, new models for supernova shocks and the dynamics of gamma-ray bursts, simulations of massive black hole accretion, fragmentation criteria in star and planet formation, models for protostellar outflows and their interaction with molecular clouds, and models for giant molecular cloud evolution.
My primary research interest in theoretical astrophysics is the study of the structure and evolution of planets, accretion discs and stars. The fluid dynamics of these objects is a topic I particularly enjoy exploring, through a combination of analytical and numerical simulation work.
Development and operation of instruments for small satellites such as BRITE Constellation. Properties and evolution of contact binary stars. Techniques for accurate computation of light curves and spectral line profiles of close binary stars, including previously neglected numerical and relativistic effects. Spectroscopy of late-type stars, their rotation and variation
Associate ProfessorExperimental astrophysics and astronomical instrumentation (IR and optical),compact objects (black holes, neutron stars, and X-ray binaries), supernovae and GRBs, supernova remnants, highly-obscured hard X-ray sourcesPh.D Cornell, 2004
My research interest lies primarily in experimental astrophysics and astronomical instrumentation, along with observational studies of various objects. I’ve developed instruments, especially infrared spectrographs (e.g., WIFIS, NIRES, MOSMAS), and am interested in advancing novel devices (e.g., polarization gratings) and techniques for astronomical applications. Observationally, I am more interested in objects with high-energy phenomena, such as supernovae and supernova remnants (both stellar and gaseous), optical transients, ultra-luminous X-ray sources and massive stars.
Stars form a crucial component of the Universe, as engines creating the elements necessary for life to being beacons for cosmological studies. I am interested in all aspects of stellar astrophysics , but have been primarily focused on the structure and evolution of intermediate- and high-mass stars to both calibrate standard candles such as Cepheids and to understand the transition from blue to yellow to red supergiants as probes of supernova progenitors using population synthesis, stellar evolution, atmosphere and hydrodynamic models along with various types of observations such as spectra, interferometry, long time series and polarization. I am also interested in using planetary transit observations to directly probe the properties of planet-hosting stars by developing new tools to fit observations using model stellar atmospheres. By better knowing those stars, we better know the planets they host.
I use variable stars to study the nature and evolution of stars. My current interest centers on
pulsating red giants and supergiants, which represent the semi-final stages of stars’ lives, and are poorly-understood, compared with other variable star types. I use archival data, especially from the
American Association of Variable Star Observers (AAVSO), which stretches back for a century or more, edit the Journal of the AAVSO, and otherwise facilitate the contributions of skilled amateurs to
variable star research. I am also engaged in a wide variety of astronomy education and outreach projects.
Professor, CITAAstrophysical sources of high energy radiation (Soft Gamma Repeaters, Anomalous X-ray Pulsars, Gamma-Ray Bursts), relativistic fluids and magnetofluids, supernova core collapse, accretion flows and — intermittently — the early universe.Ph.D. 1988 Princeton
Work Phone:416-978-8784workPersonal Email:INTERNET
Assistant Professor, UTSCComposition and Structure of Super-Earths and Mini-Neptunes, Formation processes and chemistry of Rocky Planets, Thermal evolution and Interior Dynamics of Rocky and Icy PlanetsPh.D. 2008, Harvard
The characterisation of the low-mass planets: super-Earths and mini-Neptunes. The former are planets that are mostly solid, either rocky or icy in composition, while the latter posses also a volatile
envelope. My goal is to determine if planets with masses between 1-15 Earth-masses are scaled up versions of Earth, or scaled-down versions of Neptune in terms of their composition, evolution and physical properties.
I am interested in compact objects, stars and binaries, their structure, formation and evolution, and their use to infer fundamental physical properties. My research is based on observations, but
includes interpretation, theory and numerical modelling as required. Currently, I am trying to use
neutron stars to study physics in conditions out of reach of terrestrial experiment, and to solve associated astronomical puzzles. I am also looking at the origin of SN Ia explosions (hoping to confirm our suggestion that these are due to white-dwarf me rgers, even for sub-Chandrasekhar mass), and, more generally, try to predict what types of transients should occur
My primary research interests involve the Large Scale Structure (LSS) in the Universe. By studying its properties and evolution, we can make firm statements about the physical processes which must have been active. Despite — or perhaps because of — its size, the LSS is difficult to observe, and specialized instruments and surveys are required to study it. I work on two such instruments, the South Pole Telescope (SPT), and the Canadian Hydrogen Intensity Mapping Experiment (CHIME).
I study the interiors of planets, the structure of proto-planetary disks and circumstellar dusty debris disks, the organization of planetary systems, the formataion history of moons and satellites in the solar system, and the evolution of the Kuiper Belt. Recently, I have been engaged in understanding the Kepler planetary systems, in terms of their internal structure, their dynamics and origins.
My research focuses on many aspects of high-redshift galaxy clusters. I am involved in a number of large optical/IR imaging surveys to create large samples of clusters up to redshift of 2. These provide cluster samples for projects in galaxy and cluster evolution and observational cosmology. These include spectroscopic surveys of cluster galaxies, the evolution and formation of clusters, the roles of environments in the evolution of galaxies, the morphology of galaxies in clusters, gravitational lensing, and the applications of galaxy clusters to cosmology. I also work on photometric redshift
techniques, and their applications to galaxy evolution studies involving large galaxy photometric catalogues.