Snake-like phenomena in Tore Supra following pellet injection
Snake-like phenomena in Tore Supra following pellet injection
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DOI：
10.1088/0029-5515/37/4/i03
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发表时间：
1997-04
期刊：
影响因子：
3.3
通讯作者：
A. Pecquet;P. Cristofani;M. Mattioli;X. Garbet;L. Laurent;A. Géraud;C. Gil;E. Joffrin;R. Sabot
中科院分区：
文献类型：
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作者：
A. Pecquet;P. Cristofani;M. Mattioli;X. Garbet;L. Laurent;A. Géraud;C. Gil;E. Joffrin;R. Sabot
在注入高速固体氢或氘丸后，在q=1表面内烧蚀，在Tore Supra中观察到“蛇”。它们被检测到，烧蚀后立即，作为振荡的线积分密度的中心干涉仪通道。软X射线信号中的相应振荡在约70 ms后从噪声中分离。蛇能在地震中幸存下来，但也会受到地震的影响。变化，在约500毫秒长的寿命期间，蛇半径rs的旋转频率和旋转方向进行了讨论，强调的影响，碰撞。在许多蛇中，rs/r1，其中r1是指q=1的表面的半径，是0.5的量级。蛇有一个m=1，n=1的螺旋度，指出了问题的解释方面的电流配置文件。对干涉仪和软X射线信号中蛇振荡的联合模拟表明，蛇内部的杂质（碳）密度远大于外部的杂质（碳）密度，在软X射线上，蛇形成后约80 ms出现了一个区域变化，因此，杂质（碳）的积累似乎发生在这个时候。提出了一个同时考虑杂质和自举效应的稳定性判据，其结果与Wesson（1995）提出的模型一致
`Snakes' are observed in Tore Supra after injection of high velocity solid hydrogen or deuterium pellets ablated inside the q=1 surface. They are detected, immediately after the ablation, as oscillations in the line integrated densities of the central interferometer channels. The corresponding oscillations in the soft X-ray signals detach from the noise about 70 ms later. Snakes survive sawtooth crashes, but are nevertheless affected by them. Variations, during the about 500 ms long lifetime, of the snake radius rs, of the rotation frequency and of the rotation direction are discussed, stressing the effects of the sawtooth crashes. In many snakes rs/r1, where r1 refers to the radius of the q=1 surface, is of the order of 0.5. The snake has an m=1, n=1 helicity, pointing out the problem of the interpretation in terms of current profile. Combined simulations of the snake oscillations in both interferometer and soft X-ray signals have indicated that the impurity (carbon) density inside the snake is much larger than that outside it. Since a change of regime seems to appear about 80 ms after the snake formation on the soft X-ray, it seems plausible that impurity (carbon) accumulation takes place at this time. A stability criterion taking into account both impurity and bootstrap effects is presented; the result agrees with the model proposed by Wesson (1995)