标题： ESO 320-G030 中的一个原假核球，由由核棒驱动的大量分子流入供给 显示英文标题

标题： A proto-pseudobulge in ESO 320-G030 fed by a massive molecular inflow driven by a nuclear bar

摘要： 星系中的核棒被认为能有效地将气体向内驱动，产生核星暴并可能形成活动星系核（AGN）。我们基于赫歇尔和ALMA光谱观测的分析，确认了孤立的、双棒状的明亮红外星系ESO 320-G030的这一情景。赫歇尔/PACS和SPIRE对ESO 320-G030的观测显示，在18条水蒸气线中存在吸收/发射，我们将这些与ALMA的水蒸气423-330 448 GHz线（Eupper~400 K）和连续谱图像结合，以研究核区。辐射转移模型表明，需要三个核成分来解释水蒸气和连续谱数据。一个包层，半径~130-150 pc，尘埃温度~50 K，氢分子数密度~2x10^{23} cm^{-2}，包围着一个核盘，半径~40 pc，100微米光学厚度~1.5-3（氢分子数密度~2x10^{24} cm^{-2}）以及一个极紧凑（半径~12 pc）、温暖（~100 K）且被掩埋（100微米光学厚度>5，氢分子数密度>~5x10^{24} cm^{-2}）的核心成分。这三个核成分占星系L_IR的70%（SFR~16-18 Msun yr^{-1}）。核区由在CO 2-1中通过ALMA观测到的分子流入供给，这与核棒有关。 随着半径减小（r=450-225 pc），质量流入率增加到约20 Msun yr^{-1}，这与核区恒星形成率相似，表明星暴是由流入维持的。 在较低的r处，流入最好通过远红外OH基态双线探测，估计的流入率为约30 Msun yr^{-1}。 核区气体补充的短时标约为20 Myr，表明快速的演化过程，并表明我们正在观察一个中间阶段 （<100 Myr）的原假核，它由由强核条状结构驱动的大质量流入供给。 我们还将H2O模型应用于赫歇尔远红外光谱观测的H2^{18}O、OH、\$^{18}OH、OH+、H2O+、H3O+、NH、 NH2、NH3、CH、CH^+、^{13}CH^+、HF、SH和C3，并估计它们的丰度。 显示英文摘要

摘要： Galaxies with nuclear bars are believed to efficiently drive gas inward, generating a nuclear starburst and possibly an active galactic nucleus (AGN). We confirm this scenario for the isolated, double-barred, luminous infrared galaxy ESO 320-G030 based on an analysis of Herschel and ALMA spectroscopic observations. Herschel/PACS and SPIRE observations of ESO 320-G030 show absorption/emission in 18 lines of H2O, which we combine with the ALMA H2O 423-330 448 GHz line (Eupper~400 K) and continuum images to study the nuclear region. Radiative transfer models indicate that 3 nuclear components are required to account for the H2O and continuum data. An envelope, with R~130-150 pc, T_dust~50 K, and N_H2~2x10^{23} cm^{-2}, surrounds a nuclear disk with R~40 pc and tau_100um~1.5-3 (N_H2~2x10^{24} cm^{-2}) and an extremely compact (R~12 pc), warm (~100 K), and buried (tau_100um>5, N_H2>~5x10^{24} cm^{-2}) core component. The three nuclear components account for 70% of the galaxy L_IR (SFR~16-18 Msun yr^{-1}). The nucleus is fed by a molecular inflow observed in CO 2-1 with ALMA, which is associated with the nuclear bar. With decreasing radius (r=450-225 pc), the mass inflow rate increases up to ~20 Msun yr^{-1}, which is similar to the nuclear SFR, indicating that the starburst is sustained by the inflow. At lower r, the inflow is best probed by the far-infrared OH ground-state doublets, with an estimated inflow rate of ~30 Msun yr^{-1}. The short timescale of ~20 Myr for nuclear gas replenishment indicates quick secular evolution, and indicates that we are witnessing an intermediate stage (<100 Myr) proto-pseudobulge fed by a massive inflow that is driven by a strong nuclear bar. We also apply the H2O model to the Herschel far-infrared spectroscopic observations of H2^{18}O, OH, $^{18}OH, OH+, H2O^+, H3O^+, NH, NH2, NH3, CH, CH^+, ^{13}CH^+, HF, SH, and C3, and estimate their abundances.