论文标题
HI 21厘米在无线电大风AGN中吸收，并具有双峰[OIII]发射
HI 21-cm absorption in radio-loud AGN with double-peaked [OIII] emission
论文作者
论文摘要
星系演化中的不同物理过程，例如导致双重活性银河核（AGN）结合的星系合并和从狭窄线区域散发出的流出的流出，可以在AGN的光谱上以双峰狭窄的发射线形式留下烙印。为了研究此类AGN中心的中性气体，我们使用了升级的巨型Metrewave射程望远镜（UGMRT）进行了对HI 21-CM吸收的试点调查，其光谱AGN的光谱显示了Z <= 0.4（Median z〜0.14），其光谱显示了双峰[OIII]发射线。在我们可以获得清洁光谱的八个来源中，我们在三个来源（检测率为38（+36/-20）％）中检测HI 21-CM的吸收，并找到其他两个来源吸收的初步指示。对于在基于地面的光学图像中显示相互作用或潮汐扰动签名（> 〜50％）的系统，HI 21-CM吸收的检测率比单个不受干扰的系统（〜25％）的系统高（> 〜50％）。这与Z <= 0.2 Galaxy合并中观察到的HI 21-CM吸收的高发生率一致。需要较高的空间分辨率光谱来确认HI吸收气体的起源，即，要么气体进入无线电大通AGN，流出的AGN流出气体，要么在银河尺度或环核盘上旋转的气体。
Different physical processes in galaxy evolution, such as galaxy mergers that lead to coalescence of dual Active Galactic Nuclei (AGN) and outflows emanating from the narrow line region, can leave their imprint on the optical spectra of AGN in the form of double-peaked narrow emission lines. To investigate the neutral gas in the centres of such AGN, we have conducted a pilot survey of HI 21-cm absorption, using the upgraded Giant Metrewave Radio Telescope (uGMRT), in radio-loud AGN whose optical spectra show double-peaked [OIII] emission lines at z<=0.4 (median z~0.14). Among the eight sources for which we could obtain clean spectra, we detect HI 21-cm absorption in three sources (detection rate of 38(+36/-20)%) and find tentative indication of absorption in two other sources. The detection rate of HI 21-cm absorption is tentatively higher for the systems that show signatures of interaction or tidal disturbance (>~50%) in the ground-based optical images than that for the systems that appear single and undisturbed (~25%). This is consistent with the high incidence of HI 21-cm absorption observed in z<=0.2 galaxy mergers. Higher spatial resolution spectroscopy is required to confirm the origin of the HI absorbing gas, i.e. either gas infalling onto the radio-loud AGN, outflowing gas ejected by the AGN, or gas in rotation on the galactic-scale or circumnuclear discs.
