Los Alamos Staff Help Improve U.S. Capability To Detect Underground Nuclear Explosions

LANL geophysicist Catherine Snelson
LANL News:
Los Alamos National Laboratory staff were instrumental in the fifth conventional explosion experiment as part of the NNSA’s Source Physics Experiment (SPE) series.
The SPE series, conducted at the Nevada National Security Site, advances the United States’ verification mission for detecting and understanding underground nuclear explosions.
“The goal of SPE is to understand the generation of S-waves from explosive sources,” said Catherine Snelson, a geophysicist at Los Alamos that led the Laboratory’s team. “The most recent SPE shot was a great success and has led to about three times more data than what we have acquired on previous shots.”
By conducting the experiments near the location of previous underground nuclear tests, researchers are able to better compare data from conventional and nuclear explosions. This helps to advance the United States’ capability to differentiate low-yield nuclear test explosions from other seismic activity such as mining operations and small earthquakes.
Having this advanced capability helps to identify whether state or non-state actors are hiding low-yield nuclear testing to develop or improve nuclear weapons.
This fifth experiment, known as “SPE-5”, took place on April 26 and used chemical explosives equivalent to 5,000 kilograms of TNT detonated 76 meters underground. Information is gathered on SPE-5 through a variety of technologies, including high-resolution accelerometer, infrasound, seismic, explosive performance, high-speed video, aerial-based light detection and ranging, drone-based photogrammetry and synthetic aperture radar data.
Seismic data from the SPE series are shared on the Incorporated Research Institutions for Seismology website at http://www.iris.edu/hq/ for researchers around the world to analyze. 
Members of the Los Alamos team include: Snelson, Ting Chen, Christopher Bradley, Rodney Whitaker, David Steedman, Esteban Rougier, Earl Knight, Howard Patton, Carene Larmat, Charlotte Rowe, David Yang, W. Scott Phillips, Andrew Delorey, Aviva Sussman, Jennifer Wilson, and Erika Swanson (EES-17); and Liz Miller, Emily Schultz-Fellenz, Elaine Jacobs, and Dea Musa (EES-14).
In addition to Los Alamos, the SPE team includes researchers from Livermore and Sandia National Laboratories, the Nevada National Security Site, the University of Nevada-Reno, Weston Geophysical Corp., and the Department of Defense’s Defense Threat Reduction Agency. NNSA/NA-22 funded the project.