Associated with the Sculptor Dwarf Spheroidal Galaxy
نویسندگان
چکیده
Neutral hydrogen (H I ) has been detected in the Local Group dwarf spheroidal galaxy Sculptor with the 64 m Parkes single dish and mapped with the Australia Telescope synthesis array. Most of the detected H I is in two clouds ∼ 15 − 20 away from the optical center. The gas is observed at the same systemic velocity than the stars but at ≥ 125 km s away from the Magellanic Stream components in that region. A lower limit to the H I mass of 3.0 × 10 M⊙ is derived from the synthesis observation for an (MHI/LB)≃ 0.02. This amount of H I is compatible with mass loss expected from normal giants even if only 10% of the gas is retained by the galaxy in its neutral form. Subject headings: galaxies: dwarf — galaxies: individual (Sculptor) — Local Group — ISM: H I — techniques: interferometric
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