New observations of the neutral hydrogen (H I) in and around the line of sight of the Sculptor dwarf spheroidal galaxy (dSph) are presented. The data obtained with the single-dish Parkes telescope cover a large area of 7° × 7° in the direction of the dwarf and have resolutions of 155 × 1.12 km s-1. The Australia Telescope Compact Array was used to map a smaller area of 22 × 22 centered on the direction of the dwarf with higher resolutions (350'' × 140'' × 1.65 km s-1). Many H I structures having velocities outside the range of the normal Galactic disk velocities were detected, including the two Sculptor clouds (northeast and southwest) of Carignan et al. (C98). The present study shows the total extent of the C98 clouds. We derived heliocentric radial velocities for the northeast and southwest clouds of 100.2 ± 0.9 and 105.1 ± 0.3 km s-1, respectively. The intensity-weighted mean H I velocity for both clouds is 104.1 ± 0.4 km s-1. Three different hypotheses concerning the association of the C98 Sculptor clouds were considered. The case for the clouds belonging to the Sculptor group of galaxies is found to be inconsistent with the observational data. The probability of the C98 Sculptor clouds to be Milky Way features at anomalous velocities (HVCs) superposed by chance on the Sculptor dSph is estimated to be less than 2%. The third hypothesis assumes that the clouds are physically associated with the Sculptor dSph and is supported by the following evidence: (1) the radial velocities for both clouds are very close to the optical velocity of the Sculptor dSph (ΔV = 4 ± 3 km s-1), (2) 88% of the total H I flux is contained within the optical radius of the galaxy, and (3) the clouds are located symmetrically relative to the center of the Sculptor dSph. Arguments are presented that the C98 Sculptor clouds are still gravitationally bound to the dwarf galaxy and are part of its interstellar medium. The mass of each cloud is (4.1 ± 0.2) × 104 M⊙ (northeast cloud) and (1.93 ± 0.02) × 105 M⊙ (southwest cloud) at the Sculptor dSph distance (79 kpc).
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机译：提出了在Sculptor矮球状星系（dSph）视线之内和附近的中性氢（HI）的新观测结果。用单碟Parkes望远镜获得的数据在侏儒方向覆盖了7°×7°的大面积，分辨率为155×1.12 km s-1。澳大利亚望远镜紧凑阵列用于以矮人方向为中心绘制较小的22×22区域，分辨率更高（350''×140''×1.65 km s-1）。许多H I结构的速度超出了正常银河系盘速度范围，包括Carignan等人的两个Sculptor云（东北和西南）。 （C98）。本研究显示了C98云的总范围。我们推算出东北和西南云的日心向径向速度分别为100.2±0.9和105.1±0.3 km s-1。两朵云的强度加权平均H I速度为104.1±0.4 km s-1。考虑了有关C98 Sculptor云的关联的三个不同假设。发现属于星系雕刻家组的云的情况与观测数据不一致。 C98 Sculptor云以异常速度（HVC）偶然叠加在Sculptor dSph上成为银河系特征的可能性估计小于2％。第三个假设假设云与雕刻器dSph物理相关，并得到以下证据的支持：（1）两朵云的径向速度都非常接近雕刻器dSph的光速（ΔV= 4±3 km s -1），（2）总HI通量的88％包含在星系的光学半径内，（3）云相对于雕刻器dSph的中心对称放置。有人提出，C98雕刻家云仍在重力作用下束缚于矮星系，并且是其星际介质的一部分。在Sculptor dSph距离（79 kpc）处，每朵云的质量为（4.1±0.2）×104M⊙（东北云）和（1.93±0.02）×105M⊙（西南云）。
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