Research Themes

Volatile chemistry and planet formation

C2H, HCN, and C18O emission maps observed towards the protoplanetary disk HD 163296 with ALMA.

We aim to determine how key volatile elements like C, N, and O are incorporated into planets by characterizing the abundance and distribution of volatile molecules in protoplanetary disks, and how these evolve over the timescales of planet formation. Using millimeter and IR telescopes like ALMA and JWST, we can now access both the gas and ice reservoirs available to forming planets.

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MAPS XI: CN and HCN as tracers of photochemistry in disks

An evolutionary study of volatile chemistry in protoplanetary disks

A survey of C2H, HCN, and C18O in protoplanetary disks

Ice-phase chemistry experiments

Schematic of different microphysical processes that regulate the formation of new molecules in icy mantles.

In cold interstellar regions, most volatiles condense onto dust grains to form icy mantles. Understanding the chemistry of these astrophysical ices is of fundamental importance: not only are ices the major reservoir of volatiles in star-forming regions, but they are also the primary sites where organic molecules can form. In our lab we recreate the conditions of extremely low temperature and pressure needed to explore the reactivity of ice-phase molecules and understand the origins of astrochemical complexity.

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Oxygen atom reactions with C2H6, C2H4, and C2H2 in ices

Methanol formation via oxygen insertion chemistry in ices

Kinetics and mechanisms of the acid-base reaction between NH3 and HCOOH in interstellar ice analogs

Microphysics of amorphous ices

Artist's impression of `Oumuamua outgassing H2 as it approaches the sun.

Interstellar ices exhibit an amorphous, disordered structure which impacts their microphysical behaviors like desorption and entrapment. Ice microphysics influences the distribution of volatile molecules in planet-forming environments, and can even affect the macroscopic behavior of icy planetesimals. We recently showed that the peculiar behavior of the first known interstellar object, 1I/'Oumuamua, can be explained by outgassing of molecular hydrogen that was formed and entrapped within an amorphous water-dominated ice.

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Acceleration of 1I/`Oumuamua from radiolytically produced H2 in H2O ice

HCN snowlines in protoplanetary disks: constraints from ice desorption experiments

Inheritance of interstellar chemical complexity

ALMA 1.3mm spectrum of a young protostellar disk showing emission lines from various complex organic molecules.

Star-forming regions are host to a surprisingly rich organic chemistry. It has long been suspected that this inventory of interstellar organic molecules could seed young planets with building blocks for prebiotic chemistry. We use powerful millimeter telescopes to understand how chemical complexity emerges and evolves in protostellar and protoplanetary disk environments. We also use simulations to explore how organic material can survive the chaotic journey from the interstellar medium to planetesimals.

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Ice inheritance in dynamical disk models

Organic complexity in protostellar disk candidates

A survey of CH3CN and HC3N in protoplanetary disks

Complex organic molecules towards embedded low-mass protostars

Phosphorus astrochemistry

Maps of PN emission towards the Sun-like protostar B1-a, compared to the emission of the ice sublimation tracer SO2 and the outflow tracer SiO.

Phosphorus carriers are rarely observed in the molecular interstellar medium, and we have a limited understanding of the phosphorus chemistry accompanying star and planet formation. Understanding the chemistry and inheritance of phosphorus prior to planet formation is especially important given the central role that phosphorus plays in terrestrial biochemistry. We are using spatially resolved observations and demographic surveys of phosphorus carriers in low-mass protostars to understand how phosphorus is stored in the ISM and the forms in which it may be available to forming planets.

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New detections of phosphorus molecules towards Solar-type protostars

First images of phosphorus molecules towards a proto-Solar analog

Detection of phosphorus-bearing molecules towards a Solar-type protostar