1983年11月初,美国麻省理工学院的受控热核装置Alcator C的劳孙参数nτ达到了8×10~(13)秒·厘米~(-3),首次超过劳孙判据(即热化氘氚等离子体中输出的聚变功率大于输入的加热功率的条件是离子密度n与能量约束时间τ的乘积须大于6×10~(-3)秒·厘米~(-3))。 Alcator C是一座紧凑的高场强托卡马克(其大、小半径分别为64厘米和16.5厘米,设计场强为 At the beginning of November 1983, the lab-Sun parameter nτ of Alcator C at Massachusetts Institute of Technology reached 8 × 10 ~ (13) s · cm -3, exceeding the Lawson criterion for the first time The deuterium-tritium plasma output fusion power is greater than the input heating power provided that the product of the ion density n and the energy confinement time τ is greater than 6 × 10 -3 cm -3. Alcator C is a compact, high-field tokamak with large and small radii of 64 and 16.5 cm