The M81 Group Dwarf Irregular Galaxy DDO 165. I. High Velocity Neutral Gas in a Post-Starburst System
John M. Cannon, Hans P. Most, Evan D. Skillman, Daniel R. Weisz, David Cook, Andrew E. Dolphin, Robert C. Kennicutt,, Janice Lee, Anil Seth, Fabian Walter, Steven R. Warren
备注：
The Astrophysical Journal, in press. Full-resolution version available on request from the first author
We present new multi-configuration VLA HI spectral line observations of the M81 group dIrr post-starburst galaxy DDO 165. The HI morphology is complex, with multiple column density peaks surrounding a large region of very low HI surface density that is offset from the center of the stellar distribution. The bulk of the neutral gas is associated with the southern section of the galaxy; a secondary peak in the north contains ~15% of the total HI mass. These components appear to be kinematically distinct, suggesting that either tidal processes or large-scale blowout have recently shaped the ISM of DDO 165. Using spatially-resolved position-velocity maps, we find multiple localized high-velocity gas features. Cross-correlating with radius-velocity analyses, we identify eight shell/hole structures in the ISM with a range of sizes (~400-900 pc) and expansion velocities (~7-11 km/s). These structures are compared with narrow- and broad-band imaging from KPNO and HST. Using the latter data, recent works have shown that DDO 165's previous "burst" phase was extended temporally (>1 Gyr). We thus interpret the high-velocity gas features, HI holes, and kinematically distinct components of the galaxy in the context of the immediate effects of "feedback" from recent star formation. In addition to creating HI holes and shells, extended star formation events are capable of creating localized high velocity motion of the surrounding interstellar material. A companion paper connects the energetics from the HI and HST data.
Ionized gas and sources of its ionization in the Irr galaxy IC 10
IC 10是最近的星暴不规则星系，它的WR星数量惊人。我们报告的HII区电离的星团和WR星的发射光谱的分析结果的基础上，与6米望远镜的特殊天体物理观测站的俄罗斯科学院使用MPFS场摄谱仪和SCORPIO缩焦器在狭缝摄谱仪模式下操作。根据Martin-Manjon等人（2010）提出的HII区发射线谱的新演化模型，我们确定了银河系中恒星形成区电离星团的质量和年龄。我们估计的恒星数量需要在最明亮的HII-区域HL 111的气体，并报告新的测定在HII地区的氧丰度。
