The neutral hydrogen distribution has been studied in the direction of three Galactic Wolf-Rayet (W-R) stars, using the 100 m Effelsberg radio telescope. Neutral hydrogen voids, regions of low H I emissivity, are observed over a 10–16 km s-1 velocity range for the stars WR 2 (=HD 6327), WR 128 (=HD 187282), and WR 151 (=CX Cep). These minima are interpreted as the observable 21 cm counterpart of the interstellar bubble created by the powerful winds of W-R stars and their progenitors. The H I cavities are elongated structures having an axial ratio ranging from 1.3 (WR 151) to 2.0 (WR 128). As pointed out in previous studies, the W-R stars are always off-center with respect to either the geometric center of the H I void or the absolute minimum inside the cavity. This offset ranges from 40% to 70% of the H I hole's minor axis. The major axes of these cavities are ~30 pc for both WR 2 and WR 128, and ~50 pc for WR 151. The missing H I mass amounts to 96 M⊙ (WR 128), 200 M⊙ (WR 2), and 480 M⊙ (WR 151). Some of the physical parameters of the ring nebula associated with WR 128, such as its expansion velocity, 80 ± 22 km s-1, radius, 6.3 ± 0.2 pc, and characteristic age, (7.4 ± 2.4) × 104 yr, are derived from a simple geometric model that accounts for the discrepancy between the radial velocity of the H I hole and the ring nebula related to WR 128.
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机译：已使用100 m Effelsberg射电望远镜研究了三颗银河Wolf-Rayet（W-R）星的中性氢分布。在WR 2（= HD 6327），WR 128（= HD 187282）和WR 151（= CX Cep）的恒星上，在10–16 km s-1速度范围内观察到中性氢空洞，即低HI发射率区域。 。这些极小值被解释为由W-R恒星及其祖先的强风产生的星际气泡的21 cm对应部分。 H 1腔是具有1.3（WR 151）到2.0（WR 128）的轴向比率的细长结构。正如先前的研究所指出的那样，W-R星始终相对于H I空洞的几何中心或腔体内的绝对最小值处于偏心状态。此偏移量为H I孔短轴的40％至70％。对于WR 2和WR 128，这些腔的主轴约为30 pc，对于WR 151约为50 pc。缺少的HI质量为96M⊙（WR 128），200M⊙（WR 2）和480 M⊙（WR 151）。推导了与WR 128相关的环形星云的一些物理参数，例如其膨胀速度80±22 km s-1，半径6.3±0.2 pc和特征年龄（7.4±2.4）×104 yr来自一个简单的几何模型，该模型解释了HI孔的径向速度和与WR 128相关的环形星云之间的差异。
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