论文标题
NGC 1068中CS的ALMA观察：化学和激发
ALMA observations of CS in NGC 1068: chemistry and excitation
论文作者
论文摘要
我们介绍了附近Galaxy NGC 1068（$ \ sim14 $ mpc）对Atacama大毫米/亚毫米阵列（ALMA）观察的结果。这个Seyfert 2禁止的星系拥有一个圆盘（CND，$ r \ sim200 $ PC）和一个Starburst Ring（SB环，$ r \ sim1.3 $ kpc）。这些高分辨率地图（$ \ sim0.5 $“，$ \ sim35 $ pc）使我们能够分析银河系中的特定子区域，并调查线强度比和物理条件的差异，尤其是CND和SB环，尤其是局部热力学平衡（LTE）对气体的分析cs sudiation cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons cons的持续分析均可计算，该量次数是不合格的。 radex拟合观测并限制气体温度，CS柱密度和氢密度，最终，使用化学代码uclchem来重建气体，可以深入了解其起源和化学历史AGN跨雪橇的高分辨率过渡的数量可能可以进一步限制条件，尤其是在SB环中。
We present results from Atacama Large Millimeter/submillimeter Array (ALMA) observations of CS from the nearby galaxy NGC 1068 ($\sim14$ Mpc). This Seyfert 2 barred galaxy possesses a circumnuclear disc (CND, $r\sim200$ pc) and a starburst ring (SB ring, $r\sim1.3$ kpc). These high-resolution maps ($\sim0.5$", $\sim35$ pc) allow us to analyse specific sub-regions in the galaxy and investigate differences in line intensity ratios and physical conditions, particularly those between the CND and SB ring. Local thermodynamic equilibrium (LTE) analysis of the gas is used to calculate CS densities in each sub-region, followed by non-LTE analysis conducted using the radiative transfer code RADEX to fit observations and constrain gas temperature, CS column density and hydrogen density. Finally, the chemical code UCLCHEM is used to reconstruct the gas, allowing an insight into its origin and chemical history. The density of hydrogen in the CND is found to be $\geq10^5$ cm$^{-2}$, although exact values vary, reaching $10^6$ cm$^{-2}$ at the AGN. The conditions in the two arms of the SB ring appear similar to one another, though the density found ($\sim10^4$ cm$^{-2}$) is lower than in the CND. The temperature in the CND increases from east to west, and is also overall greater than found in the SB ring. These modelling methods indicate the requirement for multi-phase gas components in order to fit the observed emission over the galaxy. A larger number of high resolution transitions across the SLED may allow for further constraining of the conditions, particularly in the SB ring.
