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arXiv 0811.3914astro-ph
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两个射电星系z~2.3的积分场谱

Integral Field Spectroscopy of two radio galaxies at z~2.3

S. F. Sanchez, A. Humphrey

摘要:

本文研究了围绕两个高红移射电星系4C40.36(z=2.27)和4C48.48(z=2.34)的巨电离气体星云的形态、运动学和电离性质。{积分场光谱观测是使用PMAS光谱仪的PPAK束进行的,安装在Calar Alto天文台的3.5米处,以覆盖每个射电星系中心的64”X 72”视场。观测跨越5个夜晚,使用两种不同的光谱分辨率(分别具有~ 4AA和~ 8AA的半高宽),覆盖从~3700 AA到~7100 AA的光学波长范围,其对应于从~1100 AA到~2000 AA的静止帧紫外范围。在该波长范围内检测到各种发射线,包括Lyalpha(1216 AA)、NV(1240 AA)、CIV(1549 AA)、HeII(1640 AA)、OIII](1663 AA)和CIII](1909 AA)。该数据集用于推导这些线中的每条线的通量强度的空间分布和气体运动学。详细研究了两个天体核区发射谱线的性质,发现这两个天体都位于一个大的电离气体星云中,其中Ly α发射的范围在100 kpc以上。CIV和HeII发射线也在空间上延伸。在4C+48.48中,在活动核的位置上,有一个低Ly-alpha/CIV的带垂直于射电轴。这一特征可能是中性气体盘边缘的观测特征。这两个星云的运动学与稳定旋转不一致,尽管它们与流入或流出并不矛盾。

英文摘要:

In this article we study the morphology, kinematics and ionization properties of the giant ionized gas nebulae surrounding two high redshift radio galaxies, 4C40.36 (z=2.27) and 4C48.48 (z=2.34).}{Integral Field Spectroscopy observations were taken using the PPAK bundle of the PMAS spectrograph, mounted on the 3.5m on the Calar Alto Observatory, in order to cover a field-of-view of 64" X 72" centered in each radio galaxy. The observations spanned over 5 nights, using two different spectral resolutions (with FWHM~4 AA and ~8 AA respectively), covering the optical wavelength range from ~3700 AA to ~7100 AA, which corresponds to the rest-frame ultraviolet range from ~1100 AA to ~2000 AA >. Various emission lines are detected within this wavelength range, including Lyalpha (1216 AA), NV (1240 AA), CIV (1549 AA), HeII (1640 AA), OIII] (1663 AA) and CIII] (1909Å). The dataset was used to derive the spatial distribution of the flux intensity of each of these lines and the gas kinematics. The properties of the emission lines in the nuclear regions were studied in detail.In agreement with previous studies, we find that both objects are embedded in a large ionized gas nebula, where Ly alpha emission is extended across ~100 kpc or more. The CIV and HeII emission lines are also spatially extended. The nebulae are generally aligned with the radio axis, although we detect emission far from it. In 4C+48.48, there is a band of low Ly-alpha/CIV running perpendicular to the radio axis, at the location of the active nucleus. This feature might be the observational signature of an edge-on disk of neutral gas. The kinematics of both nebulae are inconsistent with stable rotation, although they are not inconsistent with infall or outflow.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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