Spectral decomposition of the stellar kinematics in the polar disk galaxy NGC 4650A
Spectral decomposition of the stellar kinematics in the polar disk galaxy NGC 4650A
复制标题
极盘星系 NGC 4650A 中恒星运动学的谱分解
DOI：
10.1051/0004-6361/201424228
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Italy.
中科院分区：
文献类型：
--
作者：
L. Coccato;E. Iodice;M. Observatory;Garching;H Germany;I. Capodimonte;Naples;Italy.
上下文极环星系NGC 4650 A的原型包含两个主要的结构组成部分，一个是主星系的中心球体，以及一个延伸的极盘。光度学和运动学研究都表明，这两个组成部分共存于星系中心区域的两个不同平面上。目标。这项工作的目的是研究NGC 4650A中心区域的宿主星系和极盘的光谱和运动学性质，通过解开它们对观测到的星系光谱的贡献。
方法.我们应用光谱分解技术在以前的作品中介绍的长缝光谱观测在CaII三重态区域。我们将分析的重点放在沿着PA = 152，对应于主星系的光度短轴，这两个组件的叠加是更相关的，光谱分解是必要的。我们的目标是将在主星系赤道面运动的恒星与那些在子午线平面运动的恒星分开，子午线平面是沿着极盘运动的。
结果我们成功地解开了NGC 4650 A的两个结构成分的光谱，并测量了它们的视线速度和速度色散剖面，以及沿沿着PA = 152的恒星含量。宿主星系显示出明显的旋转沿着其光度短轴，这表明引力势不是轴对称的。极盘表现出运动学解耦：内部区域相对于外部区域和宿主球体反向旋转。这表明了一个复杂的形成历史的极盘，其特点是质量吸积与去耦角动量。
Context. The prototype of Polar Ring Galaxies NGC 4650A contains two main structural components, a central spheroid, which is the host galaxy, and an extended polar disk. Both photometric and kinematic studies revealed that these two components co-exist on two different planes within the central regions of the galaxy. Aims. The aim of this work is to study the spectroscopic and kinematic properties of the host galaxy and the polar disk in the central regions of NGC 4650A by disentangling their contributions to the observed galaxy spectrum.
Methods. We applied the spectral decomposition technique introduced in previous works to long-slit spectroscopic observations in the CaII triplet region. We focused the analysis along the PA = 152 that corresponds to the photometric minor axis of the host galaxy, where the superimposition of the two components is more relevant and the spectral decomposition is necessary. We aim to disentangle the stars that move in the equatorial plane of the host galaxy from those that move in the meridan plane, which is along the polar disk.
Results. We successfully disentangled the spectra of the two structural components of NGC 4650A and measured their line-of-sight velocity and velocity dispersion profiles, and the stellar content along PA = 152. The host galaxy shows significant rotation along its photometric minor axis, indicating that the gravitational potential is not axisymmetric. The polar disk shows a kinematic decoupling: the inner regions counter-rotating with respect the outer-regions and the host spheroid. This suggests a complex formation history for the polar disk, characterised by mass accretion with decoupled angular momenta.
DOI：
10.1046/j.1365-8711.2001.04688.x
发表时间：
2001-09
影响因子：
4.8
作者：
A. Cenarro;N. Cardiel;J. Gorgas;R. Peletier;A. Vazdekis;F. Madrid;Spain.;U. Nottingham;UK.;Instituto de Astrof'isica de Canarias-Instituto-de-Astrof'isica-de-Canarias-102997450;Observatorio de Calar Alto;Almería;Spain.
通讯作者：
A. Cenarro;N. Cardiel;J. Gorgas;R. Peletier;A. Vazdekis;F. Madrid;Spain.;U. Nottingham;UK.;Instituto de Astrof'isica de Canarias-Instituto-de-Astrof'isica-de-Canarias-102997450;Observatorio de Calar Alto;Almería;Spain.