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Latest News
WEST claims latest plasma confinement record
The French magnetic confinement fusion tokamak known as WEST maintained a plasma in February for more than 22 minutes—1,337 seconds, to be precise—and “smashed” the previous record plasma duration for a tokamak with a 25 percent improvement, according to the CEA, which operates the machine. The previous 1,006-second record was set by China’s EAST just a few weeks prior. Records are made to be broken, but this rapid progress illustrates a collective, global increase in plasma confinement expertise, aided by tungsten in key components.
J. W. Boldeman, J. Fréhaut, R. L. Walsh
Nuclear Science and Engineering | Volume 63 | Number 4 | August 1977 | Pages 430-436
Technical Paper | doi.org/10.13182/NSE77-A27060
Articles are hosted by Taylor and Francis Online.
Corrections of the large liquid scintillator measurements by Boldeman et al. and Soleilhac et al. for the delayed gamma rays from fission have produced consistent values for the average number of prompt neutrons () produced in the fission of 235U. The absolute value of for thermal-neutron fission is 2.389 ± 0.009, and the energy dependence is approximately linear. The data do not support the existence of fine structure between 200 and 600 keV nor the broad step-like structural dependence found in recent evaluations. However, there is the suggestion of a slight flattening of the curve representing the data between 250 and 600 keV.
