We present near-IR, integral field spectroscopic observations of the planetary nebula (PN) Hb 12 using Near-infrared Integral Field Spectrograph (NIFS) on Gemini-North. Combining NIFS with the adaptive optics system Altair, we provide a detailed study of the core and inner structure of this PN. We focus the analysis in the prominent emission lines [Fe II] (1.6436 μm), He I (2.0585 μm), H2 (2.1214 μm), and Brγ (2.16553 μm). We find that the [Fe II] emission traces a tilted system of bipolar lobes, with the northern lobe being redshifted and the southern lobe blueshifted. The [Fe II] emission is very faint at the core and only present close to the systemic velocity. There is no H2 emission in the core, whereas the core is prominent in the He I and Brγ recombination lines. The H2 emission is concentrated in equatorial arcs of emission surrounding the core and expanding at ~30 km s–1. These arcs are compared with Hubble Space Telescope images and shown to represent nested loops belonging to the inner sections of a much larger bipolar structure that replicates the inner one. The He I and Brγ emission from the core clearly show a cylindrical central cavity that seems to represent the inner walls of an equatorial density enhancement or torus. The torus is 02 wide (≡200 AU radius at a distance of 2000?pc) and expanding at ≤30 km s–1. The eastern wall of the inner torus is consistently more intense than the western wall, which could indicate the presence of an off-center star, such as is observed in the similar hourglass PN, MyCn 18. A bipolar outflow is also detected in Brγ emerging within 01 from the core at ~ ± 40 km s–1.
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机译：我们在双子星座-北上使用近红外积分场光谱仪（NIFS），对行星状星云（PN）Hb 12进行近红外积分场光谱观察。将NIFS与自适应光学系统Altair结合使用，我们将对该PN的核心和内部结构进行详细研究。我们将分析重点放在主要的发射谱线[Fe II]（1.6436μm），He I（2.0585μm），H2（2.1214μm）和Brγ（2.16553μm）上。我们发现，[Fe II]发射跟踪了双极瓣的倾斜系统，北瓣发生了红移，而南部瓣发生了蓝移。 [Fe II]发射在核心处非常微弱，仅在接近系统速度时才出现。核心中没有H2排放，而核心在He I和Brγ重组系中突出。 H2排放集中在核心周围的赤道排放弧中，并在〜30 km s-1处扩展。将这些弧与哈勃太空望远镜的图像进行比较，并显示它们代表了嵌套的环，这些环属于更大的双极结构的内部，该双极结构复制了内部的环。核心发射的He I和Brγ清楚地显示出一个圆柱形中心腔，似乎代表了赤道密度增强或圆环面的内壁。圆环宽02（在200？pc的距离处≡200AU半径），并以≤30km s-1扩展。内环的东壁始终比西壁强，这可能表明存在偏心星，例如在类似的沙漏PN MyCn 18中观察到的。在出现的Brγ中也检测到双极流出。在距中心约±40 km s-1处距中心01内。
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