I am a member of the JWST Mid-Infrared Instrument (MIRI) instrument and Guaranteed Time Observation (GTO) teams as well as the Near-Infrared Camera (NIRCam) GTO team. I have participated in the detector testing and characterization of MIRI ongoing at JPL and in the integrated facility testing that occurred at Goddard Space Flight Center in 2015 and at Johnson Space Center in 2017. With the GTO teams, I plan, design, and will eventually carry out JWST Cycle 1 GTO extragalactic science programs, a few of which you can read about below.
JWST/MIRI imaging in the HUDF
The Hubble Ultra Deep Field (HUDF) and surrounding area is the most well-studied patch of the sky, containing some of the deepest data (and farthest and youngest galaxies!) ever seen spanning the X-ray to the optical to the infrared to the radio. This area will be targeted by the NIRCam and NIRSpec GTO teams for the extensive JWST Advanced Deep Extragalactic Survey (JADES), which will provide early, extremely deep and wide near-infrared imaging and spectroscopy. Mid-infrared MIRI imaging will be obtained as part of JADES and US and EC lead GTO programs. Together these surveys will demonstrate the power of JWST to expand our science horizons.
The Mystery of Jellyfish Galaxies
Jellyfish galaxies are galaxies that are falling into galaxy clusters. In addition to being dense "cities" of galaxies, galaxy clusters use their deep gravity well to hold on to deep pools of hot gas. This gas creates a "wake" for the galaxies that are falling into or through the cluster, stripping off materials like gas and stars to create spectacular jellyfish tails.
This process is one of the leading contenders to explain why galaxies that live in clusters shut down their star formation earlier than galaxies outside - this process may strip off the precious gas they need to form stars. In Cycle 1, we will look at the well-studied local galaxy ESO 137-001 (right), obtaining high resolution MIRI IFU spectroscopy over 5-25.5μm at several locations spanning the galaxy-tail interface to the mid-tail. This spectral range covers multiple rotational transition of H2 and additional fine structure lines, probing shock heated hot and warm gas at and around star forming currently proceeding in the tail. These diagnostics will establish if the star formation is occurring in situ and/or was stripped from the galaxy. For more information on our JWST program, check out this press release.
Image Credit: X-ray: NASA/CXC/UAH/M.Sun et al; Optical: NASA, ESA, & the Hubble Heritage Team (STScI/AURA)
Supermassive black holes in the most dusty galaxies
Supermassive black holes are thought to play a vital role in the evolution of galaxies, particularly the most massive, luminous galaxies. However, galaxies contain dust which can obscure our view of their components. One class in particular, the Ultraluminous Infrared Galaxies (ULIRGs), are so dusty the light we normally see from the black hole (from the accretion disk and surrounding gas) cannot escape in a way we can currently see! Enter JWST, which will reveal the mid-infrared light of these galaxies, where neon gas excited by the black hole will be emitted. This signature and others provided by JWST will prove whether these ultra dusty galaxies host the black holes we expect them to.