Research 

The Gran Telescopio Canarias (GTC) is a partnership of the University of Florida, Spain, and Mexico. The GTC 10.4-m telescope, located on La Palma, Canary Islands, Spain, is the largest optical-IR astronomical telescope in the world. My team and I at U. Florida developed the GTC mid-IR camera CanariCam, which provides modes for imaging, spectroscopy, polarimetry, and coronagraphy through the N (8 – 13 μm) and Q (16 – 24 μm) atmospheric windows.

GTC copy

My research emphasizes the determination of the detailed structure of circumstellar disks around fairly young stars, those less than a few tens of millions of years old. Disks around stars younger than a million years old are likely still coalescing into planets, and determination of the disk structure provides constraints on the planet-forming environment, particularly the densities and temperatures of the coalescing solids and the shape of the disk. After a few million years or so, much of the primordial disk material, that is, that material left over from the original cloud that formed the star and disk, is used up or blown away, and the disk is converted to a so-called debris disk made of dust created from the collisions of the larger bodies—either large dust particles or planetesimals—that were formed during the earlier phase of the disk evolution. Determination of the disk structure at this phase tells us about those collisional processes, which are still important in the disk evolution. Recently I have begun using the technique of mid-IR polarimetry to determine the structure of magnetic fields in protoplanetary disks and star-forming regions. 

The tools that I use for this research are mid-IR cameras most of which were built by my team and me at the University of Florida. Mid-IR radiation is emitted by starlight-heated solid particles (“dust”) in the central few hundred astronomical units of circumstellar disks. Those are the regions where planets form, and so mid-IR imaging, spectroscopy, and polarimetry of these regions using 8 and 10 meter telescopes allows us to probe the structure of those planet-forming regions. My research on circumstellar, protoplanetary disks has included the discovery with OSCIR in 1998 of the disk around HR 4796 A and the first imaging, with T-ReCS, around Beta Pictoris, of what may be a catastrophic collision of two planets or asteroids in a young disk.

The first mid-IR camera that my team and I developed shortly after he arrived at the University of Florida in 1995 was called OSCIR. With OSCIR, we established what has become a leading IR-instrumentation program. OSCIR was commissioned at the IRTF in late 1995, and was used extensively until 2001 at the IRTF, the CTIO 4-meter telescope, the Keck-2 telescope, and both Gemini North and South. In addition to being a front-line science tool, OSCIR played a unique role in providing critical engineering support during the commissioning of the Gemini telescopes. The success of OSCIR led to the successful competition by UF, with me as PI, to build T-ReCS, a highly innovative IR imager and spectrograph that was for many years  a facility instrument at the Gemini South telescope in Chile. Subsequently, my team and I competed for, and received, the contract to build the first thermal-IR imager, spectrograph, and polarimeter to be used on the GTC, noted above. That instrument, CanariCam, achieved first light in November 2009, was commissioned in 2012, and is now available for science operations. Numerous exciting results from CanariCam have been published in the open literature. Among these is the first-ever mid-IR time-series spectra of a Type Ia supernova, SN 2014J in the galaxy M82. In addition, we are carrying out an intensive campaign of mid-IR polarimetry to determine the structure of magnetic fields in protoplanetary disks and their environments, as noted above. Recently, with colleagues at UF, STScI, and in Europe, especially Spain, I have begun developing instrumentation and science programs that take advantage of new capabilities afforded by the use of small satellites (“smallsats”).

Link to Telesco Publications (via SAO/NASA Astrophysics Data System) (Updated 13 August 2016)

TELESCOPE

There is a moment after you move your eye                                                                                                               when you forget where you are                                                                                                                                because you’ve been living, it seems,                                                                                                               somewhere else, in the silence of the night sky.

You’ve stopped being here in the world.                                                                                                                                 You’re in a different place,                                                                                                                                                  a place where human life has no meaning.

You’re not a creature in a body.                                                                                                                                                  You exist as the stars exist,                                                                                                                                  participating in their stillness, their immensity.

Then you’re in the world again.                                                                                                                                                    At night, on a cold hill,                                                                                                                                                 taking the telescope apart.

You realize afterword                                                                                                                                                                     not that the image is false                                                                                                                                                 but the relation is false.

You see again how far away                                                                                                                                                         each thing is from every other thing.

-Louise Glück