U.S. scientists conducted the first evaluation of radiation leaks during the March accident at the plant "Fukushima-1". Do they do it according to the observations amounts of radioactive sulfur in the air on the other side of the Pacific — California
Specialists in atmospheric chemistry at the University of California at San Diego conducted the first detailed quantitative study of the amount of radiation leakage that occurred during cooling sea water nuclear reactor Fukushima plant damaged by the earthquake and tsunami in March. Their work is published Proceedings of the National Academy of Sciences.
"Any act of God gives us a chance to learn a lot by analyzing what happened," — says Mark Timens, who led the work.
March 28, 2011, 15 days after plant operators began to pump sea water into the damaged reactor, the group recorded an unprecedented Timensa peak concentration of radioactive sulfur in the air in La Jolla (California, USA).
They found that the radiation source was a Japanese nuclear power plant
Leakage of nuclear reaction products, in particular neutrons, melting occurred when nuclear fuel rods. The neutrons hit the sea water pumped into the reactor. There they react with chloride ions are present in abundance in seawater (salt formula NaCl). When the neutron proton knocks of chloride, that is converted to radioactive sulfur (isotope 35S).
However, contaminated water isotope that gets into the hot reactor, instantly evaporated. To prevent an explosion of accumulated vapors, plant operators took The gas mixture — along with the radioactive sulfur — in the atmosphere.
Oxidized sulfur dioxide to oxygen and sulfate anions, with the wind and the clouds made it to California, where she was registered devices Institution of Oceanography, University of California. Observing atmospheric flows, scientists have tracked the path of air for 10 days to move from Japan to California.
Based on this, they calculated how much radiation released into the environment as a result of the accident at Fukushima.
The number of neutrons that react with chlorine to form radioactive sulfur was calculated by volume of sea water pumped into the reactor, as well as parameters of the reaction of neutrons with chloride ions. Also took into account the loss of radioactive sulfur in the way — as a result of radioactive decay, as well as losses in the lateral vortex flow. Given these factors, between March 13, when it was started pumping water into the reactor, and March 20, the external environment is allocated 400 billion neutrons per 1 sq. km. m surface cooling pools.
The concentration of radioactive sulfate over the ocean near Fukushima was 200 000 particles per cu. m, which is 365 times higher than the natural level.
Timensa group argues that the sources detected in the atmosphere of radioactive sulfur were just nuclear fuel in reactors or ponds station. Cosmic rays can cause low concentrations of radioactive sulfur in the upper atmosphere, but they rarely mix with the lower layers of the ocean, where the measurements.
For four days, March 24-28, 1501 was measured concentration of radioactive sulfur atom per cubic meter of air — is the most important in more than two years of data on this site.
Even the potential "make-up" from the stratosphere — a rare event, which leads to the natural growth of radioactive sulfur content in the lower atmosphere — could increase the concentration of only 950 atoms per cubic meters. m
At the same time, the release of radioactive sulfur from Fukushima began an interesting scientific experiment in no way connected with the accident areas.
In particular, a one-time release of "tagged" sulfur atoms allows us to trace the path of circulation of gases in the atmosphere, as well as sulfur compounds in soils of Japan. This "experiment, in particular, will help to better understand the cycles of chemical elements in the environment." This work group Timensa already started in Japan.
If you believe many reputable scientists, the tragedy at the plant Fukuima on its harmful effects even surpassed Chernobyl, and in fact, it would seem, what could be worse? The data subject by scientists removed a huge amount of supplying video, examples of such documentaries can always look online at http://dokkino.ru. Unfortunately, for many reasons, scientists can only give us the information to solve a problem created, to have ordinary people.