A Pair of Leading Spiral Arms in a Luminous Infrared Galaxy?
A Pair of Leading Spiral Arms in a Luminous Infrared Galaxy?
复制标题
发光红外星系中的一对主导旋臂？
DOI：
10.1086/595728
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
J. Kotilainen
中科院分区：
文献类型：
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作者：
P. Väisänen;S. Ryder;S. Mattila;J. Kotilainen
领先的旋臂是一种罕见的现象。我们在这里提出了少数几个令人信服的候选者之一，即旋臂在星系盘旋转时以与直觉相反的方向打开。这次在发光红外星系IRAS 18293-3413中的探测是基于甚大望远镜的近红外自适应光学成像和英澳望远镜的长缝近红外光谱。我们讨论了基于成像的星系取向，并从光谱中的发射和吸收特征推导出旋转曲线。该星系是强烈的恒星形成，在高速相遇时有一个次要的伴星。从光学图像不易追踪到18293-3413IRA的旋臂这一事实表明，对相互作用系统和LIRG进行高质量近红外成像的更大样本可能会发现更多的领先旋臂的情况，这对旋臂理论和逆行相遇造成了限制，特别是对盘质量和暗物质晕质量之间的关系。
Leading spiral arms are a rare phenomenon. We present here one of the very few convincing candidates of spiral arms opening counterintuitively in the same direction as the galaxy disk is rotating. This detection in the luminous IR galaxy (LIRG) IRAS 18293–3413 is based on near-infrared (NIR) adaptive optics imaging with the Very Large Telescope and long-slit NIR spectroscopy with the Anglo-Australian Telescope. We discuss the orientation of the galaxy based on imaging and derive rotation curves from both emission and absorption features in the spectrum. The galaxy is strongly star-forming and has a minor companion in a high-velocity encounter. The fact that the arms of IRAS 18293–3413 are not easily traceable from optical images suggests that larger samples of high-quality NIR imaging of interacting systems and LIRGs might uncover further cases of leading arms, placing constraints on spiral arm theories and retrogade encounters, and especially on the relationship between disk masses and dark matter halo masses.