The ion backflow (IBF) is the main limiting factor for operating time projection chambers (TPCs) at high event rates. A significant effort is invested by many experimental groups to solve this problem. This article explores a solution based on operating a passive bipolar wire grid. In the presence of the magnetic field, the grid more effectively attenuates the ion current than the electron current going through it. Transparencies of the grid to electrons and ions are measured for different gas mixtures and magnitudes of the magnetic field. The results suggest that in a sufficiently strong magnetic field, the bipolar wire grid can be used as an effective and independent device to suppress the IBF in TPCs.

中文翻译：

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无源双极栅极离子阻挡的测量


离子回流 (IBF) 是高事件率下运行时间投影室 (TPC) 的主要限制因素。许多实验小组投入了大量精力来解决这个问题。本文探讨了一种基于操作无源双极线栅的解决方案。在存在磁场的情况下，栅极比通过它的电子电流更有效地衰减离子电流。针对不同的气体混合物和磁场强度，测量网格对电子和离子的透明度。结果表明，在足够强的磁场中，双极线栅可以作为一种有效且独立的装置来抑制 TPC 中的 IBF。