We have discovered an extreme high-velocity bipolar CO outflow in the vicinity of NGC 2023, with total outflow velocities of ~200 km s-1. At very high velocities this outflow is jetlike with an opening angle ≤4°, while it shows a separate outflow lobe at low velocities. The outflow is bipolar and exhibits a clear mirror symmetry, which suggests that the source powering the outflow is episodic or precessing. The dynamical timescales for the outflow are ≤3000 yr. We identify the source driving the CO jet with a deeply embedded low-luminosity submillimeter double source (separation ~23''), where the primary component lies on the symmetry axis of the outflow and has all the signatures of a "class 0" protostellar object. Analysis of molecular data and (sub)millimeter photometry suggests that the driving source is cold and compact, with a luminosity of 10 L☉ and a total mass of 1.8-4.6 M☉. It has no near-IR counterpart, it drives an extremely young outflow, and it emits a large fraction of its luminosity in the submillimeter regime. Both millimeter sources have low dust emissivity, β ~ 0.8-1.3, similar to what is found for other class 0 objects, while the surrounding molecular cloud core appears to have a β ~ 2.0, the canonical value for "normal" interstellar dust in the submillimeter regime.
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机译：我们在NGC 2023附近发现了一个极端的高速双极CO流出，总流出速度约为200 km s-1。在很高的速度下，该流出物呈射流状，开度角≤4°，而在低速时显示出一个单独的流出瓣。流出是双极性的，并表现出清晰的镜像对称性，这表明为流出提供动力的源是偶发性的或旋进的。流出的动态时间尺度≤3000年。我们用深埋入的低光度亚毫米级双辐射源（间隔约23英寸）来确定驱动CO射流的源，其中主要成分位于流出的对称轴上，并具有“ 0级”原恒星的所有特征目的。对分子数据和（亚）毫米光度法的分析表明，驱动源冷而紧凑，发光度为10L☉，总质量为1.8-4.6M☉。它没有近红外对应物，它驱动了非常年轻的流出，并且在亚毫米范围内发出了很大一部分的光度。两个毫米波源的粉尘发射率都较低，β〜0.8-1.3，与其他0类物体的发射率相似，而周围的分子云核似乎具有β〜2.0，即“正常”星际尘埃的标准值。亚毫米政权。
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