Two ‘Exceptional’ Researchers Receive High-profile Award

Isaac Larsen
Isaac Larsen

The U.S. Department of Energy (DOE) this month announced that 73 scientists from across the nation, including assistant professors Scott Hertel, physics, and Isaac Larsen, geosciences, will receive funding for their investigations as part of its Early Career Research Program. Now in its tenth year, the program is designed “to bolster the nation’s scientific workforce by providing support to exceptional researchers during the crucial early career years, when many scientists do their most formative work,” DOE says.

While final figures are negotiated for each award, university-based researchers who are within ten years of receiving their Ph.D. degrees receive about $150,000 per year for five years to cover salary and research expenses.

This year, awards went to 27 scientists from DOE’s national laboratories and 46 from U.S. universities.Their research topics are required to fall within one of DOE’s six major program offices, which include advanced scientific computing, basic energy sciences, biological and environmental research, fusion energy sciences, high-energy physicsor nuclear physics.

Hertel’s research is centered on the detection of what he calls the “mysterious” Dark Matter particles that makeup the majority of the mass in the universe. If the Dark Matter particle is lighter than about the mass of a proton, he adds, it would be invisible – below any particle detector threshold ­on Earth – because it would deposit only a tiny amount of energy when it interacts.This award will fund the development of a new class ofdetectors focused at low-mass Dark Matter, allowing scientists tostudy particle physics more generally at lower energies than previously possible.

“The goal of this work is to advance an unusual particle detector technology that shows great promise at low energies,” he says. In this approach, superfluid helium serves as the target materialand a handful of evaporated helium atoms serves as the signal,” he explains. The work will take advantage of new equipment and technologies available in the Physical Sciences Building.

For his study, Larsen, a geochemist who has access to the latest technologies for quantifying soil production and chemical weathering rates, will focus on these and other variables as part of a wider investigation into “how rocks break down both physically and chemically as influenced by vegetation, climate, geology and surface processes such as landslides, and how those influence the chemistry of surface waters.” Vegetation contributes to breaking down rocks by releasing acids or other chemicals into soil, for example, and freezing and thawing, rain and snowfall all play a role.

Larsen will conduct the studies in the East River in the Colorado Rockies, a DOE study site devoted to how watersheds function. Larsen will complement his field and lab data with modeling work to make theoretical predictions about how rock dissolves in watersheds and influences water chemistry. “In this area, it has already been documented that the forest is starting to migrate upward to occupy areas that were not vegetated before,” he explains. “This will likely influence chemical weathering and eventually the chemistry of river and stream flow. DOE wants to know how climate change and other perturbations will influence watersheds, including the interaction between vegetation and soils.”

The broader DOE study looks at how perturbations to watersheds influence water resources, such as how snowpack changes will influence availability of water, and how forest fires will change water quality. Water is used in so many types of energy production and is vital to the millions of people who rely on it downstream, he adds.

For some geochemical analyses, Larsen plans to collaborate with scientists at UMass and two DOE national labs, Lawrence Berkeley and Lawrence Livermore, where there are special facilities such as a “giant mass spectrometer,” he notes. “I’ll be really curious to see if we can isolate a signal of biology influencing the production and weathering of soils,” he says. “I'm not the first person to work on this, but I want to try to incorporate more variables than others have done, such as vegetation, topography, rock type and rock strength in order to tease apart the most important factors. The more variables you consider, the more data you have to get at the interactions that might be going on.”