Lawson criterion

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Lawson criterion

A necessary but not sufficient condition for the achievement of a net release of energy from nuclear fusion reactions in a fusion reactor. As originally formulated by J. D. Lawson, this condition simply stated that a minimum requirement for net energy release is that the fusion fuel charge must combust for at least enough time for the recovered fusion energy release to equal the sum of energy invested in heating that charge to fusion temperatures, plus other energy losses occurring during combustion. The Lawson criterion is to be thought of as only a rule of thumb for measuring fusion progress; detailed evaluation of all energy dissipative and energy recovery processes is required in order properly to evaluate any specific system. See Nuclear fusion

Lawson criterion

[′lȯs·ən krī‚tir·ē·ən]
(plasma physics)
The requirement for the energy produced by fusion in a plasma to exceed that required to produce the confined plasma; it states that for a mixture of deuterium and tritium in the temperature range from 1 × 108 to 5 × 108 degrees Celsius, the product of the ionic density and the confinement time must be about 1014 seconds per cubic centimeter.
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At temperatures of 3 keV observed in the Large Helical Device (LHD) experiment, the TRAN code predicts an energy confinement time of 160 ms, which agrees with measured values (11).
36) On appeal, the court looked at the issues of: (1) whether it was error for the military judge not to instruct the members to consider Davidson's pretrial confinement in determining their sentence; (2) whether it was error for the staff judge advocate not to advise the convening authority to consider the pretrial confinement; and (3) whether it was illegal for the accused to serve more confinement time than authorized under the UCMJ for the offense when his pretrial confinement was added to his adjudged confinement at hard labor.
Lawson showed that in order to achieve net power from a conventional electric power plant, the fusion plasma must be sustained at or above a temperature of about 5 keV such that the product of its density and confinement time exceed a certain value.
The courts determine what we term "actual confinement time," but YOPB decides whether the ward can be paroled before his or her date of maximum confinement.
Besides temperature, break-even requiresanother criterion: the product of plasma density and confinement time, usually called the LAwson criterion.
section] 3585(b), and determined the statute required the DOJ to credit federal prisoners with state pretrial confinement time not otherwise applied against another sentence.
Their confinement time is cut short however, when a mysterious alien robot lands on Earth and begins storming the country.
The confinement time in this experiment, 20 seconds, was less than the 60 seconds of the DCX-1 device, a conventional experiment chosen for comparison.
The energy confinement time is about 10 ins, several times the usual empirical scaling.
5 MW of heating power from a combination of neutral beams, ECH and ICH sources and that the electron temperature has reached 10 keV and ion temperature of 2 keV at a density of 5 x 10(18) m3, with an energy confinement time of 0.
5 tau_skin where tau_E is the energy confinement time and tau_skin is the time for the plasma current profile to redistribute at fixed current).
While the popularly known version states that the product of the fuel density and energy confinement time must be at least 10[sup.