Lawson criterion

(redirected from Confinement time)

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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Successful fusion also requires that the product of three factors -- a plasma's particle density, its confinement time, and its temperature -- reaches a certain value.
Remember that the managerial flexibility confinement time is in fact exercised by the farmer, but intuitively and without some form of proper measurement of the financial value arising from this.
For confinement fusions, sufficient density and confinement time are required as specified by Lawson criterion[1].
Positron confinement time depends on trap imperfections.
In simulations we compare observations of the energy confinement time with a third of the test particle confinement time.
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.
Nevertheless, the value of the three combined parameters has increased many times over the past 10 years, with the most improvement in confinement time.
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.
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.