The turbulence of magnetically confined plasmas usually presents high-density pulses with short duration known as bursts. In the Texas Helimak, it is possible to suppress bursts in a broader region by applying a negative electrostatic bias. However, an almost unchanged burst rate persists in a region far from the location where bias is applied. We investigate the turbulence transition that occurs from the burst suppressed region to the burst dominated region by analyzing data from Langmuir probes in the whole radial extension of the machine. We find that such turbulence transition can be understood as an alternation of two different turbulent regimes, with the probability of being in each regime depending on the radial position. One regime, named as burst-free regime, consists of only Gaussian fluctuations and the other, named as bursty turbulent regime, is a train of pulses with double exponential temporal profiles, exponential amplitude distribution, and random occurring instants. This succession between burst-free and bursty turbulent regimes influences the equilibrium parameters.

中文翻译：

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德州Helimak中湍流政权的共存

磁约束等离子体的湍流通常会在短时间内提供高密度脉冲，称为脉冲。在德州Helimak中，可以通过施加负静电偏压来抑制更广泛区域中的爆发。但是，几乎没有变化的突发速率在远离施加偏置的位置的区域中持续存在。我们通过分析机器整个径向延伸过程中Langmuir探针的数据，研究了从爆裂抑制区域到爆裂主导区域发生的湍流过渡。我们发现，这种湍流过渡可以理解为两种不同湍流状态的交替，每种状态的概率取决于径向位置。一种被称为无猝发状态的状态仅由高斯波动组成，而另一种则由高斯起伏组成。被称为突发湍流状态的是一系列具有双重指数时间分布，指数幅度分布和随机发生瞬间的脉冲。无爆裂和爆裂湍流状态之间的这种连续影响平衡参数。