IMS Detects Radioactive Gases From N. Korean Nuclear Test

The Comprehensive Test Ban Treaty Organization (CTBTO) announced on April 23 that its International Monitoring System (IMS) detected radioactive isotopes consistent with the February 12 North Korean nuclear test and announced the discovery on April 23, 2013. The radionuclide station in Takasaki, Japan detected xenon-131m and xenon-133, two radioactive isotopes that are associated with nuclear fission.

The gases detected by the Takasaki station, located approximately 620 miles from the North Korean test site, were produced by a nuclear fission event that occurred at least 50 days before detection. The IMS was able to identify the North Korean test site as a possible source for the noble gases.

In an April 25 op-ed "Detection of North Korea Test Shows CTBT Can Be Verified," Jon Wolfsthal, Deputy Director of the James Martin Center for Nonproliferation Studies, said that the CTBTO's verification performance following the February 12 nuclear test "all but put[s] to rest" concerns regarding the organization's ability to detect underground nuclear tests. According to Wolfsthal, "the CTBT is effectively verifiable."

Visit the CTBTO website for additional details.

Watch the CTBTO video to see how the IMS analyzed the data.