Credit: T. Robitaille and R. Hurt, GLIMPSE Team, NASA/JPL

Research

During my life as a researcher, one of my main interests was the study of the formation of stars and clusters throughout the Milky-Way Galaxy, and linking such studies - where individual young stars can be resolved most of the time - to other galaxies where we can often only view star forming regions as a whole.

To study star formation in our own Galaxy, I worked with the large volumes of archival multi-wavelength data available, which included many Galactic plane surveys, and modeled the data using radiative transfer techniques, which can be used to simulate observations of protostars, star forming clouds, or entire galaxies.

Galactic Star Formation

Using the GLIMPSE survey, a survey of the Galactic plane from 3.6 to 8.0 microns, I carried out a census of young and evolved stars in the Galactic mid-plane (Robitaille et al., 2008 ). The result of this study was a sample of over 10,000 candidate forming stars in our Galaxy. Using this census, I then developed a population synthesis model, to estimate the rate at which stars are forming in our Galaxy, and found a value on the order of one solar mass per year (Robitaille and Whitney, 2010). I am now interested in using the GLIMPSE data in combination with other Galactic plane sureys to study how the properties of forming stars and pre-main-sequence stars with protoplanetary disks vary from region to region and depend on environment.

As a member of the GLIMPSE team, and in collaboration with Robert Hurt, I produced large mosaics of the whole Galactic plane, which have been used for publicly released images (such as the one at the top of this page, and the 360-degree panorama available from here).

Radiative Transfer

As part of my modeling work, I developed a parallelized three-dimensional Monte-Carlo dust continuum radiative transfer code - Hyperion - that is described in detail in Robitaille et al., 2011. More information about the code can be found at the main Hyperion website, and collaborated on a number of projects making use of this new code, modeling comets, pre-main-sequence stars with protoplanetary disks, protostars, star formation regions, and whole galaxies. While I have now left research, I am still actively maintaining Hyperion and working with scientists who want to use it.

The following animation shows a 3-d visualization of the density and temperature structure around a forming star in a simulation by Stella Offner. The temperature structure has been computed self-consistently using Hyperion:

Spectral Energy Distribution modeling

During my PhD, and in collaboration with Barbara Whitney, I computed a large grid of model spectral energy distributions of young (< 10Myr) stars with circumstellar disks and envelopes, and have developed a tool to fit these models rapidly to a given set of observations. This allows us to understand which physical parameters - such as stellar, disk, or envelope parameters - can be constrained. The models and the fitting tool are both publicly available.

Press

I have been involved in the following press releases/featured stories:

Publications