标题： 宇宙再电离末期一个 z=6.42 类星体寄主星系中的原子和高激发态分子气体成像：充足的质量供给支持爱丁顿极限恒星爆发 显示英文标题

标题： Imaging Atomic and Highly Excited Molecular Gas in a z=6.42 Quasar Host Galaxy: Copious Fuel for an Eddington-Limited Starburst at the End of Cosmic Reionization

摘要： 我们利用Plateau de Bure干涉仪的观测，获得了z=6.42类星体SDSS J114816.64+525150.3（以下简称J1148+5251）宿主星系中的CO(J=7-6)和CI(3P2-3P1)发射线。 显示CO(J=7-6)发射的区域被空间分辨出来，其大小为5千秒差距，与早期的CO(J=3-2)观测结果很好地一致。 结合该源碰撞激发线的修订模型，这表明由CO J=7-6线追踪的高度激发分子气体是次热激发的（仅显示出CO J=3-2亮度的58+/-8%），但并未更集中于中心。 我们还在J1148+5251宿主星系中检测到了CI(3P2-3P1)发射线，但该线太弱，无法进行可靠的空间尺寸测量。 从CI(3P2-3P1)线的流量中，我们推导出总原子碳质量为M_CI=1.1x10^7 M_sun，相当于总分子气体质量的大约5x10^-4倍。 我们还搜索了H2O(J_KaKc=2_12-1_01)发射线，得到了灵敏的线亮度上限L'_H2O<4.4x10^9 K km s pc^2，即小于CO(J=3-2)亮度的15%。 在这颗类星体宿主星系中，宇宙再电离末期的温暖、高度激发的分子气体、原子气体和尘埃维持着强烈的恒星爆发，其表面密度达到千秒差距尺度上由（尘埃消光）限制的爱丁顿极限恒星形成所预测的水平。 显示英文摘要

摘要： We have imaged CO(J=7-6) and CI(3P2-3P1) emission in the host galaxy of the z=6.42 quasar SDSS J114816.64+525150.3 (hereafter: J1148+5251) through observations with the Plateau de Bure Interferometer. The region showing CO(J=7-6) emission is spatially resolved, and its size of 5 kpc is in good agreement with earlier CO(J=3-2) observations. In combination with a revised model of the collisional line excitation in this source, this indicates that the highly excited molecular gas traced by the CO J=7-6 line is subthermally excited (showing only 58+/-8% of the CO J=3-2 luminosity), but not more centrally concentrated. We also detect CI(3P2-3P1) emission in the host galaxy of J1148+5251, but the line is too faint to enable a reliable size measurement. From the CI(3P2-3P1) line flux, we derive a total atomic carbon mass of M_CI=1.1x10^7 M_sun, which corresponds to ~5x10^-4 times the total molecular gas mass. We also searched for H2O(J_KaKc=2_12-1_01) emission, and obtained a sensitive line luminosity limit of L'_H2O<4.4x10^9 K kms pc^2, i.e., <15% of the CO(J=3-2) luminosity. The warm, highly excited molecular gas, atomic gas and dust in this quasar host at the end of cosmic reionization maintain an intense starburst that reaches surface densities as high as predicted by (dust opacity) Eddington limited star formation over kiloparsec scales.