Research
I arrived at WVU in January 2009 from the NRAO in Green Bank, WV where I worked as a postdoc. I previously worked at the Naval Research Lab and the Australia Telescope National Facility. I received my Ph.D. from the University of Wisconsin-Madison in 2001 and my B.S. from Yale in 1996.
I am an astronomer interested in how galaxies form and evolve. I use
radio telescopes around the world primarily to study neutral hydrogen
(HI) in our own Milky Way and other, more distant galaxies.
Around our own galaxy, the Milky Way, I helped conduct the Galactic All-Sky Survey (GASS) of the HI in the southern sky made using the Parkes radio telescope. GASS was combined with data from the Effelsberg radio telescope to produce the HI4PI survey of HI over the entire sky. The survey is shown below:
Further away, I am studying the gas in the circumgalactic medium (CGM) and intergalactic medium (IGM) around nearby galaxies. This gas could serve as fuel for future star formation in these galaxies. This work is being done using the Green Bank Telescope (GBT) and Parkes. An example of this diffuse HI can be seen around NGC 2403 and NGC 6946:
My collaborators and I are also using the GBT to conduct and extensive, deep HI survey of the CGM of M31. More information and the processed data can be found at gbthings.phys.wvu.edu/m31.
This work is continuing with a large legacy survey called IMAGINE using the ATCA+Parkes in Australia and MHONGOOSE, a key project on the MeerKAT in South Africa. These surveys involve extremely deep observations of HI in and around nearby galaxies.
I am also working to study how the HI content of galaxies evolves over the history of the universe. The CHILES survey is a 1000-hour survey using the Jansky Very Large Array (VLA) in New Mexico to observe HI evolution over the past four billion years. This project has led me to work on using WVU's High Performance Computing facilities to calibrate and image the full survey in an automated fashion while still allowing for easy manual assessment of the data quality. Going forward, the LADUMA survey will be using MeerKAT to probe the HI content of galaxies over the past eight billion years.
Another aspect of my research involves radio studies of luminous
compact blue galaxies (LCBGs). These are prolifically star-forming
galaxies that are common in the distant universe, but are exceedingly
rare today. I am studying LCBGs
in the local and distant universe in order to better constrain the current nature
and evolutionary fate of LCBGs.
Finally, my students and I have been working to develop and commission phased array feed (PAF) technology as radio cameras on telescopes around the world. This includes working with engineers at Brigham Young University, NRAO, and the Green Bank Observatory to build and deploy the Focal L-band Array for the GBT (FLAG; front end receiver and back end computers are pictured below) and with astronomers at ASTRON on Apertif.
For my research I use radio telescopes around the world, including the GBT in West Virginia, the VLA in New Mexico, Arecibo in Puerto Rico, the ATCA and Parkes in Australia, the Westerbork Synthesis Radio Telescope (WSRT) in the Netherlands, and the Giant Metrewave Radio Telescope (GMRT) in India. I have worked with astronomers in China to develop the science case for HI observations with the Five-hundred-metre Aperture Spherical radio Telescope (FAST). I am looking forward to using MeerKAT in South Africa, the South African Square Kilometer Array pathfinder telescope.
Publications
My complete list of publications can be found at this Astrophysical Data Systems link: Publication List.
The same list ranked by citation can be found at this link: Citation Ranked.
Teaching
I teach both astronomy and physics classes at WVU to both undergraduate and graduate students. These include: ASTR106-Descriptive Astronomy, PHYS301-Computational Physics, PHYS332-Theoretical Mechanics 2, ASTR368-Astrophysics 2, ASTR701-Computational Astrophysics and ASTR703-Galactic Astronomy.
For students, the course webpages can be found on eCampus.
If you want more information about these courses, or getting an undergraduate or graduate degree in Physics, look at the university catalog or our department webpage: physics.wvu.edu.
Outreach
Through generous support from a NSF CAREER grant, I have developed an open-ended, inquiry-based educational activity for middle school students: What are those THINGS?
I also have a passion for all things to do with baseball. See this video I contributed to on the Physics of Baseball and the associated article in WVU Magazine.